Marion Tilmant

Mélanie Serrero

Florian Poullenot

Guillaume Bouguen

Benjamin Pariente

Romain Altwegg

Paul Basile

Jérôme Filippi

Pierre Vanelslander

Anthony Buisson

Ariane Desjeux

David Laharie

Eric Le Balch

Maria Nachury

Lucile Boivineau

Guillaume Savoye

Xavier Hebuterne

Laurent Poincloux

Lucine Vuitton

Franck Brazier

Clara Yzet

Adnane Lamrani

Laurent Peyrin-Biroulet

MD Mathurin Fumery
email: fumery.mathurin@chu-amiens.fr

Celltrion Janssen

MSD Mayoli-Spindler Cilag

Laurent Peyrin

PV, AB, AD DL, ELB, MN, LB , GS, XH , LP, CY, FB, LV Jf

Endoscopic balloon dilation of colorectal strictures complicating Crohn's disease: a multicenter study

Keywords: endoscopic balloon dilatation, Crohn's disease, colonic strictures Crohn's disease, CD, EBD, endoscopic balloon dilation, UC, ulcerative colitis, IBD, inflammatory bowel disease

de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

INTRODUCTION

Crohn's disease (CD) is a chronic progressive and destructive conditions [START_REF] Pariente | Development of the Lémann index to assess digestive tract damage in patients with Crohn's disease[END_REF].

Colorectal strictures are observed in 8 to 14% of patients with CD [START_REF] Yamazaki | Malignant colorectal strictures in Crohn's disease[END_REF][START_REF] Lovasz | Risk of colorectal cancer in Crohn's disease patients with colonic involvement and stenosing disease in a populationbased cohort from Hungary[END_REF][START_REF] Sonnenberg | Epithelial dysplasia and cancer in IBD strictures[END_REF][START_REF] Fumery | Detection of Dysplasia or Cancer in 3.5% of Patients With Inflammatory Bowel Disease and Colonic Strictures[END_REF][START_REF] Bettenworth | A Pooled Analysis of Efficacy, Safety, and Long-term Outcome of Endoscopic Balloon Dilation Therapy for Patients with Stricturing Crohn's Disease[END_REF]. The natural evolution of these strictures is poorly understood. In addition to the obstructive symptoms observed in most patients, the occurrence of colonic strictures raises concerns about the risk of malignant complications. The risk of dysplasia or cancer associated with colorectal strictures varies among studies and ranges from 0.5 to 7% in CD [START_REF] Yamazaki | Malignant colorectal strictures in Crohn's disease[END_REF][START_REF] Lovasz | Risk of colorectal cancer in Crohn's disease patients with colonic involvement and stenosing disease in a populationbased cohort from Hungary[END_REF][START_REF] Sonnenberg | Epithelial dysplasia and cancer in IBD strictures[END_REF]. Diagnosing neoplastic lesions from endoscopic biopsies is challenging in clinical practice and their absence in endoscopic biopsies cannot formally rule out the presence of dysplasia/cancer [START_REF] Fumery | Detection of Dysplasia or Cancer in 3.5% of Patients With Inflammatory Bowel Disease and Colonic Strictures[END_REF]. Furthermore, non-passable strictures limit the endoscopic monitoring of disease activity and the surveillance of dysplasia of the upper colon. Endoscopic balloon dilation (EBD) has become a standard of care for small bowel strictures [START_REF] Bettenworth | A Pooled Analysis of Efficacy, Safety, and Long-term Outcome of Endoscopic Balloon Dilation Therapy for Patients with Stricturing Crohn's Disease[END_REF]. The recent ECCO-ESCP guidelines recommend EBD for the management of colonic strictures in CD [START_REF] Bemelman | ECCO-ESCP Consensus on Surgery for Crohn's Disease[END_REF]. However, the level of these recommendations is very low, as no dedicated study has specifically evaluated the effectiveness and safety of EBD in colonic strictures. Most data on EBD come from small-bowel strictures or pooled analysis. Adujar et al. compared the effectiveness of EBD of 49 colonic strictures complicating inflammatory bowel diseases with those of ileal strictures. After a median follow-up of 40 months, 30% of the patients with colonic stricture required a surgery or the placement of a stent [START_REF] Gomollón | 3rd European Evidence-based Consensus on the Diagnosis and Management of Crohn's Disease 2016: Part 1: Diagnosis and Medical Management[END_REF]. A study by the Ann Arbor group reported similar results in 46 patients with colonic strictures complicating CD, with 34% of surgery after a median of follow-up of 40 months [START_REF] Rieder | European Crohn's and Colitis Organisation Topical review on prediction, diagnosis and management of fibrostenosing Crohn's disease[END_REF].

We therefore aimed to evaluate the effectiveness and safety of EBD for colonic strictures in patients with CD in a multicenter retrospective study.

MATERIALS AND METHODS

Study population

Nine French academic centers with a database including all consecutive IBD patients who underwent EBD were selected. Inclusion criteria were patients: (i) with CD diagnosis according to ECCO guidelines [START_REF] Navaneethan | Endoscopic balloon dilation in the management of strictures in Crohn's disease: a systematic review and metaanalysis of non-randomized trials[END_REF], (ii) being ≥ 18 years of age, and (iii) having had at least one EBD for native or anastomotic rectal or colonic stricture between 1999 and 2018.

Data collection

Clinical, endoscopic, surgical, and pathological data were retrospectively extracted from patient hospital medical records using a standardized questionnaire that was developed specifically for this study. The following clinical data were collected: age, sex, date of IBD diagnosis, disease location, age at diagnosis and at the time of dilation, previous and current treatments, and previous surgery. The following information concerning strictures were collected: symptomatic character, location, number, type (native or anastomotic), duration, length, presence of ulcerations on the stricture and/or colon, passable (or not) with the endoscope, and histological results of biopsies. The collected EBD data were the number of procedures, balloon diameter, passable or not after the procedure, clinical efficacy, associated complications and modifications in IBD therapy at the time of dilation. The collected data during follow-up until last news were colonic resection and diagnosis of dysplasia or cancer.

Definitions and outcomes

Stricture was defined according to the ECCO definition as a fixed, localized and persistent colonic narrowing [START_REF] Rieder | European Crohn's and Colitis Organisation Topical review on prediction, diagnosis and management of fibrostenosing Crohn's disease[END_REF]. Endoscopic failure was defined by the need for surgical colonic resection or the persistence of obstructive symptoms at the end of follow-up. Technical efficacy was defined by a passable stricture after the EBD, clinical efficacy as an improvement of obstructive symptoms after dilation according to physician judgement. All major complications related to the procedure requiring hospitalization, transfusion, urgent endoscopic or surgical intervention were recorded for safety assessment.

Statistical Analysis

Categorical variables are expressed as percentages. Continuous variables are reported as the median with interquartile range [IQR]. The distribution of the time to surgery from the 1st dilation was estimated using the non-parametric method of Kaplan-Meier. Factors related to surgery were assessed using a univariate survival model (Cox) by calculating a Hazard-Ratio (HR) with a 95% confidence interval. For the multivariate Cox model, a backward selection method was used. All data analysis was performed using SAS® version 9.4 software (SAS Institute, Cary, NC). Survival curves were constructed using R 3.2.3 software. The protocol was approved by the Amiens University Hospital Ethics Institutional Reviews Board committee according to French guidelines (PI2019-843-0033).

RESULTS

Study population

We identified 57 patients who underwent 161 EBD procedures for 60 colorectal strictures between 1998 and 2018. The main characteristics of the population are presented in Table 1. About half of patients (52%) had ileocolonic location. Twentyfive patients (44%) were female and the median age at EBD was 36 years (IQR, 31-48). Twenty-two (39%) patients had at least one intestinal resection prior to EDB, including 9 (15%) with segmental colonic resection. At the time of dilation, 73% had been previously exposed to thiopurines, 70% to anti-TNF treatment, 7% to vedolizumab, and 5% to ustekinumab therapy.

Stricture characteristics

The stricture characteristics are presented in Table 1. The median time between CD diagnosis and stricture diagnosis was three years (IQR, 5 -20). Thirteen (23%) patients had more than one stricture and 42 (74%) had stricture-related symptoms.

Fifty-two (87%) strictures were native and the most common location was the left colon (28%). Most strictures (n = 39, 65%) were short (< 5 cm) and 35 (59%) were ulcerated. Only three strictures (5%) were passable before dilation. Biopsies were performed on 37 strictures (68%) and only one (2.7%) of them was malignant at the time of dilation, with a diagnosis of lymphoma (biopsies performed during the same procedure).

Endoscopic balloon dilation

A median of two dilations (IQR, 1-3) was performed per patient with 30 patients who had only one dilatation. At stricture dilation, 35 (53%) had biological signs of inflammation, as defined by CRP > 5 mg/L and/or calprotectin > 250 µg/g, and 44 (77%) had endoscopic ulcerations. CD medical therapy was changed for 22% (n = 36/161) of cases after dilation.

Short and long-term effectiveness

Technical efficacy was achieved for 116 of 147 dilations performed (79%) in patients with non-passable strictures. In patients with stricture-related symptoms, clinical efficacy was observed for 77% of dilations (n = 88/115). After a median of follow-up of 4.3 years [2.0 ; 8.4], 24 patients (42%) underwent a colonic resection for stricture and 24 (42%) were asymptomatic without surgery. The cumulative risk of colonic resection at one, three and five years were 19% [9; 30], 34% [21; 47], and 47% [32; 62], respectively (Figure 1). Outcomes at the end of follow-up are presented in Figure 2. Nine patients (16%) had a non-passable and symptomatic stricture, 11 (19%) a non-passable but asymptomatic stricture, 8 (14%) a passable stricture and 5 (9%) had no stricture, without surgery. One colorectal cancer was diagnosed in one of 57 patients (1.7%). The diagnosis was made on the operative specimen after segmental colonic resection. Three patients (5.3%) underwent hospitalization for stricture-related obstructive symptoms. In univariate analysis, disease duration (HR, 0.99; CI95% [0.98; 0.99], p= 0.005), strictures length (HR, 2.68; CI95% [0.88; 8.16], p= 0.083), and number of dilation (HR, 0.76; CI95% [0.58; 1.01], p= 0.057) were associated with surgery. In multivariate analysis, only disease duration remains significantly associated with surgery (HR, 0.99; CI95% [0.98; 0.99], p= 0.005) (Table 2).

Safety

Of the 161 dilations performed, only one perforation occurred (complication rate of 0.6% per procedure, 2% per patient). No other complication during follow-up was reported.

DISCUSSION

Colorectal strictures in CD are frequently diagnosed but their management remains a challenge in clinical practice. First, colonic strictures are associated with a high rate of obstructive symptoms. Second, they raise concerns about neoplastic complications that cannot be fully excluded by negative endoscopic biopsies [START_REF] Fumery | Detection of Dysplasia or Cancer in 3.5% of Patients With Inflammatory Bowel Disease and Colonic Strictures[END_REF].

Third, non-passable strictures limit the endoscopic monitoring of disease activity and the surveillance of dysplasia of the upper colon. On the opposite, segmental or total colectomy are associated with a significant morbidity [START_REF] Bemelman | ECCO-ESCP Consensus on Surgery for Crohn's Disease[END_REF][START_REF] Gomollón | 3rd European Evidence-based Consensus on the Diagnosis and Management of Crohn's Disease 2016: Part 1: Diagnosis and Medical Management[END_REF][START_REF] Tekkis | A comparison of segmental vs subtotal/total colectomy for colonic Crohn's disease: a meta-analysis[END_REF].

The recent ECCO-ESCP guidelines recommend EBD or segmental resection for colonic strictures in CD [START_REF] Bemelman | ECCO-ESCP Consensus on Surgery for Crohn's Disease[END_REF]. However, these recommendations are based on a low level of evidence, because no study has specifically evaluated the effectiveness and safety of EBD in IBD colonic strictures.

Most data on EBD come from small-bowel strictures or pooled analysis. A systematic-review [START_REF] Hassan | Systematic review: Endoscopic dilatation in Crohn's disease[END_REF] including 24 studies and 1,163 patients with CD and EBD on small-bowel or ileo-colonic anastomotic stricture reported a technical efficacy of 90%, a clinical efficacy of 80%, and a surgical rate of 27% [START_REF] Bettenworth | A Pooled Analysis of Efficacy, Safety, and Long-term Outcome of Endoscopic Balloon Dilation Therapy for Patients with Stricturing Crohn's Disease[END_REF]. Here, we have observed a technical success of 79% and a clinical efficacy of 77%, demonstrating that EBD of CD colonic strictures is an effective and safe procedure. After a median follow-up of 4 years, we observed that about 40% of patients with EBD of colonic strictures were asymptomatic without surgery. On the other hand, 42% of patients need colonic resection. There are several possible explanations for the relatively frequent resort to surgery in our study. The only goal of EBD in the treatment of small-bowel strictures is to improve obstructive symptoms, whereas dilation of colonic strictures must also allow exploration of the entire stricture and make it possible to cross it to properly, in order to examine the colon upstream. The technical success rate, which may be slightly lower for colonic strictures, was 79% in our study versus 83 to 100% for small-bowel strictures [START_REF] Bettenworth | A Pooled Analysis of Efficacy, Safety, and Long-term Outcome of Endoscopic Balloon Dilation Therapy for Patients with Stricturing Crohn's Disease[END_REF][START_REF] Hassan | Systematic review: Endoscopic dilatation in Crohn's disease[END_REF][START_REF] Navaneethan | Endoscopic balloon dilation in the management of strictures in Crohn's disease: a systematic review and metaanalysis of non-randomized trials[END_REF][START_REF] Morar | Systematic review with meta-analysis: endoscopic balloon dilatation for Crohn's disease strictures[END_REF]. This may also be related to a smaller number of anastomotic strictures in our study. In addition, the greater fear of neoplastic complications in patients with colonic stricture (in comparison with those with smallbowel stricture) results in a lower threshold for surgery in this situation. However, reported data show that high-grade dysplasia or colorectal cancer is observed in 1.2% of patients with CD and 7% of patients with UC, even if endoscopic biopsies are negative [START_REF] Fumery | Detection of Dysplasia or Cancer in 3.5% of Patients With Inflammatory Bowel Disease and Colonic Strictures[END_REF]. The non-passable character of the stricture and the inability to properly explore it and detect dysplasia or CRC in the upstream colon are factors that may influence clinicians to perform surgery. Ultimately, these factors make it difficult to compare our rate of surgery with the data available on small-bowel strictures. Of note, no dilation was proposed to UC patients during the study period. The greater fear of a neoplastic complication in this population probably explains systematic colonic resection.

The major concern for EBD is the risk of perforation. The complication rate, based on available data, varies between 0 and 4% [START_REF] Bettenworth | A Pooled Analysis of Efficacy, Safety, and Long-term Outcome of Endoscopic Balloon Dilation Therapy for Patients with Stricturing Crohn's Disease[END_REF][START_REF] Hassan | Systematic review: Endoscopic dilatation in Crohn's disease[END_REF][START_REF] Navaneethan | Endoscopic balloon dilation in the management of strictures in Crohn's disease: a systematic review and metaanalysis of non-randomized trials[END_REF][START_REF] Morar | Systematic review with meta-analysis: endoscopic balloon dilatation for Crohn's disease strictures[END_REF]. Only one study reported a higher rate, with 10.3% perforation, occurring exclusively for colonic stricture [START_REF] Singh | Efficacy and safety of endoscopic balloon dilation of symptomatic upper and lower gastrointestinal Crohn's disease strictures[END_REF]. In our study, we report only one (0.6%) major complication. This result is similar to the data available for ileal stricture.

Our study had several limitations, mainly linked to its retrospective design. The lack of standardization of the dilation procedure may have influenced our results. Also, the lack of power linked to our small population limits the identification of factors associated with EBD success. In multivariate analysis, only disease duration remains significantly associated with surgery but with an HR, 0.99; CI95% [0.98; 0.99] therefore limiting the interpretation and applicability of this result. Our study also had several strengths, including the fact that patients were included consecutively from 9 different centers. This is currently the largest cohort of EBD of colonic strictures in IBD. Finally, the 52-months median follow-up period allowed us to evaluate the longterm effectiveness of EBD.

In conclusion, EBD of CD colorectal strictures is safe and effective. About 40% of patients were asymptomatic without surgery at the end of the follow-up period. These results must be confirmed by prospective studies, but they confirm the room of EDB in the algorithm for management of colonic strictures in CD.

Tables

Figure 1 .Figure 2 :

 12 Figure 1. Probability of surgery since the first endoscopic balloon dilation

Table 1 .

 1 Characteristics of the population. IBD: inflammatory bowel disease, IQR: interquartile range.

	N = 57

Table 2 .

 2 Univariate analysis of factors associated with delay to surgical resection for colorectal stricture. HR, Hazard-Ratio ; CI, confidence interval

		Univariate analysis	Multivariate analysis
	Variable	HR [CI95%], p-value	HR [CI95%], p-value
	age	1.01 [0.98; 1.04] p= 0,683
	Symptomatic stricture	1.22 [0.45; 3.32] p= 0,7
	Disease activity	1.48 [0.44; 5.01] p= 0,528
	Disease duration	0.99 [0.98; 0.99] p= 0,005	0.99 [0.98; 0.99] p= 0.005
	Stricture length	2.68 [0.88; 8.16] p= 0,083
	number of strictures	0.83 [0.34; 2.03] p= 0,688
	ulcerated	0.83 [0.37; 1.9] p= 0,664
	Stricture location	1.24 [0.89; 1.73] p= 0,212
	Anastomotic stricture (vs	0.73 [0.21; 2.48] p= 0,608
	native)
	Balloon diameter	1.04 [0.88; 1.23] p= 0,635
	Number of dilatations	0.76 [0.58; 1.01] p= 0,057
	Therapeutic modification	0.67 [0.27; 1.62] p= 0,37

Study funding: None.

Ethical statement :

The protocol was approved by the Amiens University Hospital Ethics Institutional Reviews Board committee according to French guidelines (PI2019-843-0033).


Kaat Philippe
email: kaat.philippe@inrae.fr

Sylvie Issanchou

Sandrine Monnery-Patris

Contrasts and ambivalences in French parents' experiences regarding changes in eating and cooking behaviours during the COVID-19 lockdown

Keywords: COVID-19, qualitative research, families, eating behaviors, gender differences, emotions

Using open-ended questions, this study explored parents' experiences regarding changes in their family's food-related behaviours during the first COVID-19 lockdown in France (March-May 2020). Parents (N=498, 72% mothers) of children aged 3-12 years described which food-related changes they (1) perceived as positive during the lockdown, (2) perceived as negative, and (3) would like to maintain after the lockdown. A thematic analysis revealed that parents appreciated the choice of more local, fresh foods, the time to prepare food (homemade dishes, new recipes) and cooking and eating together with the family. In contrast, some parents highlighted a burden imposed by the increased food preparation at home. They also described a higher intake of unhealthy, palatable food (or the temptation to do so), and weight concerns. Parents would like to maintain their choice of local, fresh foods, and to continue spending more time together around food but doubt the feasibility after the lockdown. The results revealed many inter-and intra-individual contrasts in parents' answers. An ambivalent attitude toward food pleasure was demonstrated: the sensory/commensal pleasure of eating versus the concerns about an increased intake of pleasurable food. Additionally, gender differences were observed: mothers perceived the preparation of additional meals, for example, more often as a burden than fathers. This study revealed intimate perceptions of the impact of the lockdown on eating habits in families. They give insight into possible facilitators and barriers (e.g., time) for the adoption of recommended eating and cooking behaviours in families, beyond the pandemic.

Introduction

In 2020, the highly contagious coronavirus SARS-CoV-2, also known as COVID-19, has induced a pandemic. Many countries took measures to avoid the spread of this virus among their inhabitants and to avoid a collapse of hospitals. In France, a first lockdown was imposed from March until May 2020, with a profound impact on people's habits. Schools, non-food stores and leisure centres were closed, working from home was enforced except for those with essential jobs (e.g., in hospitals, food shops), and leaving your home was only allowed for a limited number of predetermined reasons (e.g., grocery shopping, medical visits, etc.).

Since both adults and children were enforced to take most of their meals at home during the lockdown, this study wanted to explore how this impacted families' eating, feeding, cooking and food shopping behaviours. The study setup was twofold: there was a quantitative part aiming to map the changes in families' food-related habits (see [START_REF] Philippe | Child eating behaviors, parental feeding practices and food shopping motivations during the COVID-19 lockdown in France: (how) did they change?[END_REF], and a qualitative part aiming to explore how parents experienced these changes. The current article focusses on this second, qualitative part of the study.

Eating behaviours consist mainly of habits, i.e., automatic associations between specific context cues and responses, which are hard to change [START_REF] Wood | Psychology of habits[END_REF]. Changes in the environment, such as induced by the COVID-19 pandemic, could cause changes in people's habits as they have to engage in a new non-automatic process of decision making [START_REF] Verplanken | Interventions to break and create consumer habits[END_REF]. Qualitative data could provide insight into the drivers and barriers for certain changes and into the perceived impact of these changes on families, even beyond the scope of COVID-19. They could help us to gain insight into the factors that could be useful to consider when promoting healthy eating and feeding behaviours in families. A recent systematic review [START_REF] Wolstenholme | Childhood fussy/picky eating behaviours: a systematic review and synthesis of qualitative studies[END_REF] highlighted the added-value of a qualitative approach for targeting families' experiences, perceptions and emotions regarding children's eating behaviours.

Moreover, it is well described in the literature how emotional factors and the family mealtime atmosphere can impact parents' and children's eating behaviours. For example, experiencing stress or negative emotions can make people overeat and reach for "comfort foods", rich in sugar and calories (Evers, Dingemans, Junghans, & Boevé, 2018;[START_REF] Michels | Stress, emotional eating behaviour and dietary patterns in children[END_REF][START_REF] Rodríguez-Martín | Food craving: New contributions on its assessment, moderators, and consequences[END_REF]. [START_REF] Hughes | Child temperament, parent emotions, and perceptions of the child's feeding experience[END_REF] have observed a negative relationship between positive parent emotions and problems in feeding children fruit and vegetables. [START_REF] Berge | Childhood obesity and interpersonal dynamics during family meals[END_REF] have shown that positive food-related family dynamics at family meals were associated with a reduced risk of childhood overweight. It is therefore interesting to study how parents experienced the COVID-19 lockdown in France and how this was related to changes in their families' eating behaviours.

Therefore, the present qualitative study aimed to explore which food-related changes parents perceived as positive during the lockdown (1), which changes they perceived as negative (2), and which changes they would like to maintain after the lockdown (3), by using open-ended questions. To our knowledge, no data have been published yet on parents' personal experiences and emotions related to changes in their families' eating and feeding habits during the lockdown. They could make a valuable contribution to the COVID-19 literature on changes in the food domain that is currently dominated by quantitative studies.

In addition, at the start of the pandemic, some studies (e.g. Alon, Doepke, Olmstead-Rumsey, Tertilt, 2020 (USA); Andrew et al., 2020 (England); [START_REF] Carlson | Changes in Parents' Domestic Labor During the COVID-19 Pandemic[END_REF] (USA)) and media coverage (e.g., Ascher, 2020 (England)) discussing the impact of the COVID-19 measures, drew the attention to gender inequalities and divisions within families.

They pointed out that women took up more childcare and household work than men during the pandemic, and showed a profound impact on women's work-life balance. The COVID-19 pandemic also had a major impact on the work life of many adults and possibly also their financial situation (ILO, 2021). Therefore, the secondary goal of the present study was to compare the experiences of parents regarding food-related changes during the lockdown based on their sex (mothers vs. fathers), their work status during the lockdown (working outside the house vs. working from home vs. at home, not working), and their perceived financial situation (comfortable vs. difficult).

Method

Study design

As mentioned previously, this study is part of a mixed-method research project, including a quantitative and qualitative part. An online survey with closed-ended questions (quantitative part) and open-ended questions (qualitative part) was used to obtain data. The quantitative part of the survey aimed to describe possible changes in French families' eating behaviours and feeding practices during the COVID-19 lockdown compared to the period before the lockdown. The results of this part are described in a different publication [START_REF] Philippe | Child eating behaviors, parental feeding practices and food shopping motivations during the COVID-19 lockdown in France: (how) did they change?[END_REF].

The qualitative part of the survey aimed to explore parents' experiences regarding changes in their family's eating and feeding behaviours and is the object of the current publication. Three open-ended questions were used to obtain data for this qualitative part. For the first question, parents were asked to describe changes related to their own or their child's/ family's eating that they perceived as positive during the period of the lockdown, compared to the period before the lockdown. For the second question, they were asked to describe changes they perceived as negative. For the third question, they were asked to describe which changes they would like to maintain after the lockdown.

Recruitment and ethics

Parents were recruited online via an agency disposing of a large panel of French respondents.

They were eligible to participate if they had at least one child aged 3-12 years living with them during the lockdown. This age range was chosen because these children are still highly dependent on their caregivers for food intake. The online survey was anonymous and parents were asked to tick a box indicating that they understood and accepted the study information and data protection policy. Participation was possible from the 30 th of April until the 10 th of May 2020 (the end of the first strict lockdown in France) and a compensation, a voucher of six euros, was offered after survey completion. An ethical approval (n°20-686) was obtained for this study from the Institutional Review Board (IRB00003888, IORG0003254, FWA00005831) of the French Institute of Medical Research and Health, and a study registration was done by the data protection service involved (CNRS).

Data analysis

The responses of the parents were analysed inductively with the use of the qualitative data analysis software NVivo in the original language of the survey (French). A thematic analysis was conducted following the steps proposed by [START_REF] Braun | Using thematic analysis in psychology[END_REF]: (1) familiarization with the data, (2) initial coding generation with a data-led approach, (3) searching for themes based on initial coding, (4) theme definition and labelling. Steps 1-3 were performed manually and independently by two authors on the first 250 answers (50%) of each of the three questions. After comparison and obtaining consensus on the generated themes and initial coding, the first author coded all answers in NVivo, and the coding was checked by the other authors. A separate analysis was performed for each question. All three authors were involved in step 4.

As the sample size was quite large, some steps proposed by [START_REF] Feng | Maximizing NVivo utilities to analyze open-ended responses[END_REF] were followed in parallel to those of [START_REF] Braun | Using thematic analysis in psychology[END_REF] in order optimize the analyses by using different NVivo utilities. A word frequency analysis was performed for each of the three open-ended questions, using a frequency query with words with stemmed variants (e.g., "cuisine", "cuisiner", "cuisinons", "cuisiné"), in order to identify patterns more easily [START_REF] Jackson | Concept mapping as an alternative approach for the analysis of open-ended survey responses[END_REF] and to limit bias regarding overweighing [START_REF] Onwuegbuzie | Validity and qualitative research: An oxymoron?[END_REF]. However, as this approach also has the reputation to decontextualize words, this analysis was only performed as a check for the search of themes. After text coding all responses, matrix coding was performed for each question to allow comparison between different groups of parents. Three comparisons were performed; one based on parents' sex (mothers (n=357) vs. fathers (n=141)), one based on parents' work status (working outside the house (n=103) vs. working from home (n=175) vs. at home, not working (n=175)), and one based on parents' perceived financial situation (comfortable (n=239) vs. difficult (n=254)).

For this last comparison, the group of parents with a more comfortable situation included those parents who indicated "It's OK" or "At ease" when asked about their financial situation.

The group with a difficult situation included those parents who indicated "Should be careful", "You get by but only just" or "You can't make ends meet without going into debt". Parents who indicated "I do not want to answer" (n=5) were not included in the comparison. For the comparison based on work status, we also did not include parents who indicated that they had another work status (n=45), since this group was so diverse. The matrixes show the number of coded responses and verbatims for each theme and subtheme for each group separately. Chisquared tests were performed to identify significant differences. The verbatims presented in this article were translated from French to English by an English linguist who lives in France and knows the French food culture. The original French verbatims with their translation are presented in Appendix 1.

Results

A total of 498 parents (72% mothers) with at least one child aged 3-12 years answered the open-ended questions. All departments in France were represented except Corsica and the oversea territories, with most parents living in Île-de France (18.7%), Auvergne-Rhône-Alpes (13.7%), Grand Est (10.6%) and Hauts-de-France (10.4%). Details about all other parental characteristics are presented in Table 1.

For each of the three open-ended questions, several themes and subthemes emerged from the thematic analysis. Overall, themes and subthemes were similar for the three different openended questions, meaning that parents described both positive and negative experiences regarding these themes. Table 2 presents the different themes and subthemes for each of the questions and the number and percentage of parents who described content that was coded into these (sub)themes. 1.0 0 0.0 a Aspects of food preparation which were unspecified (e.g., "I cook more"). Note: all the (sub)themes evoked by more than 20 parents (4% of our sample) are in bold.

Positive food-related experiences during the lockdown 172

Fifty-three parents reported either no change in their family's eating behaviours or no positive 173 changes. The other parents (almost 90%) described a multitude of changes they perceived as 174 positive during the lockdown. The most frequently mentioned themes were related to time,

Food choice and food preparation

Parents expressed their appreciation for their choices of more fresh, seasonal, and local foods. This was often related to an increased choice of fruits and vegetables. Some parents also mentioned that the lockdown gave them the opportunity to pay more attention to the nutritional value of foods and meals, and stimulated them to provide a diversity of foods and balanced meals.

"Much more fresh seasonal fruit and vegetables."

"I have more time on my hands to prepare more balanced dishes."

Different aspects related to food preparation were perceived as positive during the lockdown. Parents described increases in home-made dishes and meals (e.g., desserts, midafternoon snacks "goûters", main meals) and in the preparation of elaborated dishes that are time-consuming. Some parents also expressed the joy of trying new recipes, stimulating variety in their meals or trying out new flavours. The sources of these new recipes were not always revealed, but if revealed, television programs were a popular source of inspiration.

"I cook a few more new recipes to vary everyone's enjoyment."

"We prepare more elaborate recipes thanks to a TV program on M6 (a tvchannel in France)."

Sociability and commensality

Cooking and eating together with the family was appreciated to a high extent. Not only were there more occasions to do so, but if it took place, there was also more time to eat at a calm pace. This also had consequences for the meal atmosphere at home and on children's eating behaviours. Some parents described that children had more interest in and accepted certain foods more easily when they had helped to prepare them.

"We eat all our meals together and have more time to prepare and enjoy them." "The meal is eaten in a calm atmosphere, less tense. The children eat more easily healthier foods than they used to."

Cooking with the child was not only a pleasurable activity: for some parents, it was also the occasion to educate their children about food, to pass on certain cooking skills and values around food, and to make them taste new flavours.

"Through preparing food as a family, I teach my child how to cook, how to bake. I explain to him that vegetables are good for his health that he will be big and strong by eating them." 10 "I take time to try out new recipes. My two children participate more willingly to help me, they are proud of doing so, eat more easily when they have participated. If the recipe doesn't work out, they are also more motivated to try again. We all take time together; it allows me to try and pass on a bit of knowhow and share family anecdotes during the conversation."

Food pleasure

The joy of preparing and eating pleasurable food was very present in parents' answers.

Parents tried their best to prepare food the family loves, enjoyed the process of planning and preparing these meals, and to taste them together.

"Food has become more pleasurable, so it's positive." "I take more time to cook and please my family, I buy more locally and choose things that we fancy." "I prepare a lot more home-made food and I try to vary the recipes and to please my family. I cook a lot more pastries with my son, who loves doing that.

And my husband is really happy." Time

The notion of time was present in a majority of parents' answers. Time was cited as a factor that gave families the opportunity to plan meals and moments together, to prepare meals that are normally time-consuming, and to spend time together around food.

"Time has stopped a little and we live at a slower pace, we want to treat ourselves and pay more attention to our food than before. We prepare a lot more home-made food. We find more time to cook, even if we continue to work at the office, because we go out less." "Having fewer time constraints (no school, no telecommuting) we have time to cook as a family and choose exactly what we want to eat, so automatically it is healthier and more varied."

Negative food-related experiences during the lockdown

Even though a high number of parents (n=129) reported either no change during the lockdown or no negative change, the majority of parents (74%) described a diversity of aspects they perceived as unpleasant or negative.

Choice of palatable foods

In contrast to the choice of more fresh, local products (e.g., fruits and vegetables), which parents perceived as positive, parents also described an increased choice of palatable, energydense foods and foods high in sugar. Some of these foods and dishes were bought (e.g., candy, chocolate, ice cream), others were prepared at home (e.g., home-made cakes).

"Home-made food is maybe much more fatty or calorific." "More frequent treat yourself buys (ice cream, cakes...)."

"Tendency to make a lot of cakes and therefore snack more generously."

Quantity of (unhealthy) foods

In addition to an increased choice for palatable foods, many parents described an increased consumption or even an « overconsumption » of these foods during the lockdown. Both an increase in frequency of eating was described as increased portion sizes.

"We certainly snack more between meals." "All the same, we do eat more than before." Some parents did not describe an actual increase of intake, but described a struggle with the temptation to eat and with sensations of hunger. From their answers, it is unclear whether they have also given in to the described temptations or not.

"We are more tempted to snack." Sometimes, parents mentioned reasons (or excuses) for their changed eating behaviours.

Emotions, such as stress, anxiety, and tiredness were frequently mentioned: there was a need for food to cope with the emotional challenges that arose during the lockdown. Some parents also explained that simply taking more time to eat stimulated eating bigger quantities, or that more time at home and boredom induced more snacking or stimulated the preparation of more energy-dense, sugary food.

"Personally, stress made me snack more (feeling hungry) and so I put on weight." "More junk food to compensate for stress." "More calorific meals, more need to prepare things that make you feel good." "We eat more fatty, comforting food to make the lockdown seem less harsh for the children." "My daughter is bored so she wants to snack between meals from time to time." "More time at the table at lunchtime, bigger meals so a little weight gain...." "Being at home all day so we tend to snack more and eat sweets, biscuits..." "Well, who says more time says more baking, so more sweet things." Even though most parents described an increased intake or appetite, some parents also described a lack of appetite and weight loss which they attributed to the stress and emotions accompanying the lockdown.

"Me on the other hand, I don't eat much and normally I am really epicurean. I lost 7 kilos in 2 months, I am in good health but stress always causes me to lose my appetite, in fact I am afraid for my loved ones, I am also angry that I am going through this and that my 4 year old son is going through it too, I am a bit depressed and as a result I don't eat enough, I am a rather nervous person so my stomach has knotted up and I eat little or very little."

Weight concerns

The increased intake of foods and a lack of activity during the lockdown were associated with weight gains in certain families, or with concerns about possible weight gains. Some parents reported this weight gain or related concerns explicitly: "Feel hungrier, significant weight gain because of stress." "I bake a lot more, which makes everyone happy, but everyone is putting on weight."

Others referred to it in a more indirect way; for example, by describing a lack of physical activity during the lockdown and by comparing calorie intake during versus before the lockdown. Some parents also described a combination of these factors.

"We tend to eat as much as we did before the lockdown, which is a problem because we have less physical activity." "Meals have more calories than before and we don't exercise."

As cited previously, there were also some parents who lost appetite during the lockdown and reported weight loss.

Practical inconveniences

Beside negative emotions linked to increased intake and possible weight gains, parents also described a number of practical inconveniences. Taking more meals at home meant preparing more meals and this was perceived as a burden by some parents. Especially the time invested in meal preparation and the lack of inspiration to vary meals everyday was challenging and provoked negative emotions and stress.

"We have to cook every day and at every meal without exception. You need to find ideas to vary your meals and adapt the amount of shopping you do because you have to buy more than usual. Shopping is also more expensive. More meals to prepare, which means we have to make the same dishes over and over again because we run out of ideas."

According to parents, the lockdown was also accompanied by a changed offer in food stores and higher costs. They also had to put more effort in planning their food shopping as it was recommended to limit trips outside the house. Different reasons were provided for an increase in food costs: some families described increased costs due to increased food purchases during the lockdown, others described that a changed offer in food stores forced them to buy more expensive food brands. Some families also decided or were forced to do their food purchases in different food stores with different prices (e.g., stores closer to home).

"It is more difficult to find certain products." "More shopping to do and with an increased food budget. More difficult to do the shopping because I know I'm not going to go back straight away... so you mustn't forget anything."

"No possibility to go to my usual producers so as to reduce travel."

Aspects to maintain after the lockdown

Ninety-eight parents reported no changes or no wish to maintain changes that occurred during the lockdown. In parallel to the positive experiences, the remaining parents (80%) reported the wish to maintain their choice of more fresh, seasonal, and local foods, to maintain the preparation of home-made, elaborated meals and to take more time to cook and eat together with the family.

"I want to continue using seasonal fruit and vegetables. The pleasure of eating them and getting my family to eat more thanks to all the on-line recipes you can find." "Continue to support local producers and allow time to go to the market with my children so that they can discover even more things and be even more eager about food."

Parents expressed a wish to maintain certain changes after the lockdown, but some also questioned the feasibility. They were not sure if they would be able to do so when they return to their habits from before the lockdown, often due to an anticipated lack of time. This was not always indicated literally by parents, but could often be deduced from the use of the conditional tense of the verbs. Some parents already suggested some solutions to overcome these challenges; they, for example, want to try to invest more effort in meal planning and to prepare bigger quantities of home-made dishes and freeze them for later.

"We would like to maintain the quality of our meals however to prepare this takes up time..."

"Prepare all the meals as a family but with work commitments it's a bit complicated." "Eat more vegetables, shop less regularly but in larger quantities and organized for the week."

The ambivalent relation with food pleasure

The answers also revealed an ambivalent relation with food pleasure among some parents.

When answering the question about positive food-related experiences during the lockdown, many parents mentioned different aspects of food pleasure. Some parents referred to pleasure related to the types of food: e.g., the joy of eating "pleasurable food" or preparing foods that bring joy to the family, while other parents referred to the social aspects of food pleasure: the joy of preparing foods together, eating together, sharing moments around food.

In contrast, when answering the question about negative experiences and referring to food pleasure, the focus was predominantly on the types of food consumed: "pleasurable foods" and often preceded by an indication of quantity: e.g., "more", "much more", "too many" pleasurable food.

In some parents, the ambivalent relation with food pleasure was visible within a single verbatim, and was usually expressed as an answer to the question concerning negative experiences (-). Here, parents directly contrasted positive and negative sides of increased food pleasure during the lockdown.

(-): "I'm baking a lot more, which makes everyone happy, but everyone is putting on weight." (-): "We indulge ourselves more, so we have a dessert after every lunch in addition to the fruit! Often, it's an ice-cream that we eat outdoors in the sun, so of course it's more sugar, but at the same time it's good for morale!" (-): "At the weekend we treat ourselves and have an aperitif at lunchtime, so soda and crisps twice a week."

For other parents, the ambivalent relation was only uncovered when looking at the answers to the different questions on an intra-individual level. These parents reported positive and negative sides of food pleasure as a response to different questions ((+): positive experiences, (-): negative experiences, (M): changes to maintain). In this last verbatim, the mother appreciated preparing home-made mid-afternoon snacks ("goûter") and she would like to continue doing so, but she also thought it was a negative habit to take a mid-afternoon snack as an adult. This shows that she was well aware of French health recommendations that discourage snacking in adults, but not the mid-afternoon snack in children. She knew that her snacking behaviour during the lockdown (which she seems to appreciate) was not perfectly in line with the recommendations.

There are also answers in which parents classify the consumption of certain types of food as "negative", in line with social norms and health recommendations, but at the same time present excuses or reasons to exonerate their behaviour. They state for example that the increased intake was "reasonable" or that overall, they have "a varied diet". Easter was also a popular argument, as this is a period in France when it is socially acceptable to eat chocolate and sweets. Some parents even seemed to present eating chocolate during Easter as a cultural necessity.

"No negative change in our eating habits, or maybe the desire to eat a little bit more than before the lockdown but still reasonably." "Due to eating home-made cakes, I don't know the sugar and fat content, but my daughter has a varied diet..." "A few more sweets but it was Easter-time." "We probably eat a bit richer, especially in terms of pastries. And maybe some more sweet snacks. But hey, you have to eat the Easter chocolates."

Differences between groups of parents

Fathers versus mothers

The results of the matrix coding, allowing comparison between fathers' and mothers' responses, revealed differences for each of the three questions (Table 3).

Regarding positive experiences, proportionally more mothers reported appreciating aspects related to food preparation during the lockdown: they enjoyed having more time to prepare home-made meals and to try out new recipes.

Regarding negative experiences, proportionally more fathers reported either no changes during the lockdown or no changes that were perceived as negative. Compared to fathers, mothers mentioned more often that they perceived aspects related to food preparation negatively during the lockdown: for them, it was more often a burden to prepare an increased number of home-made meals and to come up with new recipes and vary the meals, especially for those mothers who were still working during the lockdown.

"Working in a hospital, a bit too worn out to cook." "I spend a lot of time in the kitchen!!"

Furthermore, it were also dominantly mothers who struggled with an increased desire to eat, the temptation to eat, and with sensations of hunger during the lockdown or who reported this temptation for their child or the family in general.

"Having the urge to eat all the time." "He tends to snack a bit more because he's at home."

Regarding changes to maintain after the lockdown, proportionally more fathers than mothers reported that they would like to maintain the increased choice of sustainable foods (local, seasonal) and of qualitative foods and meals. Compared to fathers, more mothers reported that they would like to maintain the positive social aspects (eating together, cooking 425 together) and having more time for cooking and for trying new recipes. 426 Aspects of food preparation which were unspecified (e.g., "I cook more"). Note. Percentages that present gender differences are in bold; significance levels of Chi-squared tests: * p < 0.10, ** p < 0.05, *** p < 0.001

Parents with a different work status

Regarding positive experiences, proportionally fewer parents who were at home without work reported appreciating an increased choice of sustainable foods compared to parents who worked outside the house and parents who worked from home (6%, 13% and 16%, respectively, p < 0.05; see Appendix 2 -Table A). Fewer of these parents who were at home without work also described appreciating the consumption of unhealthy/ palatable foods compared to parents who worked from home (2% and 7%, respectively, p < 0.1).

Proportionally more parents who worked at home reported appreciating baking own bread than parents who worked outside the house and parents who were at home without work (6%, 1% and 1%, respectively, p < 0.05).

Regarding negative experiences, proportionally more parents working outside the house reported either no changes during the lockdown or no changes that were perceived as negative compared to those parents at home with or without work (35%, 26% and 22%, respectively, p < 0.1).

Regarding changes to maintain after the lockdown, proportionally more parents who were at home without work reported that they would like to continue eating together with the family compared to parents who were working outside the house and working from home (12%, 6% and 5%, respectively, p < 0.05).

Parents with a comfortable versus difficult perceived financial situation

Regarding positive experiences, proportionally fewer parents with a difficult perceived financial situation discussed increased healthiness during the lockdown compared to parents with a comfortable financial situation (2% and 5%, respectively, p < 0.1; see Appendix 2 -Table B).

Regarding negative experiences, proportionally more parents with a comfortable financial situation reported either no changes during the lockdown or no changes that were perceived as negative compared to parents with a difficult situation (30% and 22%, respectively, p < 0.05).

Furthermore, proportionally more parents with a difficult situation described negative experiences with regard to nutrition/diversity/balance (1% and 6%, respectively, p < 0.05), the quantity of foods consumed (11% and 6%, respectively, p < 0.1), the preparation of meals (5% and 2%, respectively, p < 0.1), and finances/prices (9% and 5%, respectively, p < 0.1).

Regarding changes to maintain after the lockdown, proportionally more parents with a comfortable financial situation reported that they would like to maintain the positive meal atmosphere (4% and 1%, respectively, p < 0.05).

Discussion

The results of this qualitative study provided intimate insight into parents' positive and negative experiences regarding changes in their family's eating and feeding habits during the first COVID-19 lockdown in France. Parents also expressed which changes they would like to maintain after the lockdown.

Generally, the thematic analyses revealed changes in eating and feeding habits that are in agreement to those reported in recent quantitative studies and surveys in France and in Europe: for example, an increase in the preparation of home-made food and comfort food, more time spent cooking with children, and an increased choice of sustainable foods (local, seasonal) (e.g., Di Renzo et al., 2020; EIT Food, 2020; L'Observatoire E. Leclerc des nouvelles consommations, 2020; Marty, de Lauzon, Labesse & Nicklaus, 2021; Santé Publique France, 2020). In agreement with other reports (e.g., EIT Food, 2020;[START_REF] Loopstra | Vulnerability to food insecurity since the COVID-19 lockdown[END_REF]Santé Publique France, 2020;[START_REF] Zerbini | Food access and insecurity during COVID 19 -Evidence from France[END_REF], some parents in the current study also reported difficulties to purchase certain foods in food stores and higher prices.

In addition, the qualitative analyses did not only reveal which food-related changes occurred in families during the lockdown, but also which changes parents perceived as positive or negative and what they would like to maintain. Overall, the results showed that the positive experiences were multifactorial: parent expressed their appreciation for different food choices, increased time for food preparation and social food-related activities (cooking and eating together, sharing). For the negative experiences, the focus was predominantly on the choice for unhealthy, palatable food and on quantitative aspects: food portions, frequency of eating or food shopping outings, prices, weight, etc. What parents liked to maintain was, logically, in line with their positive experiences; the most common themes were food choice, food preparation and spending time together.

When taking a transversal look at parents' answers to the different questions, they reveal many contrasts (on inter-individual level) and ambivalences (on intra-individual level).

First, there were contrasting inter-individual opinions and experiences regarding the theme "food preparation". For a majority of parents, it was a real joy to have more time during lockdown for preparing home-made meals and for experimenting with new recipes, while other parents perceived the additional time in the kitchen as a burden and reported a lack of cooking inspiration. Here, it is good to keep in mind that in France, children have a four-or five-component lunch at school: a starter (e.g., raw vegetables), a protein dish (e.g., meat, fish, eggs), garnish (vegetables, pulses, potatoes, grain products), a dairy product, and a dessert. Variety, a balanced diet, and adaptation to children's nutritional needs are key concepts for these lunches (GEM-RCN, 2015). For some adults, it is similar at their work place. As this culinary script is strongly embedded in French culture, it is possible that parents experienced pressure to provide a similar script at home during the lockdown, when both children and adults were at home. For some parents, it may have been challenging to match the variety of recipes and nutritional balance at home, which was also expressed by some parents in the current sample.

In addition, the comparison of mothers' and fathers' answers showed that it was almost exclusively mothers reporting a perceived burden of the additional meals to prepare during the lockdown. Before the lockdown, women were, on average, already more involved in household and care activities such as food management, than men (Eurostat, 2019). There was some hope that the lockdown would bring more gender equality in household duties, and some studies did report an increase in men's participation in housework and childcare during the lockdown (e.g., Farré, Fawaz, González, & Graves, 2020 (Spain); Mangiavacchi, Piccoli, & Pieroni, 2020 (Italy); Yerkes et al., 2020 (Netherlands)). However, in several countries, women shouldered most of the extra unpaid work at home during the lockdown and reduced their working hours (e.g., Collins, Landivar, Ruppanner, & Scarborough, 2020 (USA); Craig & Churchill, 2020 (Australia); Farré et al., 2020 (Spain)). The COVID-19 pandemic thus appeared to have increased gender inequalities in (paid and) unpaid work, and this was even the case in a country like Iceland which scores well on gender equality indexes [START_REF] Hjálmsdóttir | I have turned into a foreman here at home": Families and work-life balance in times of COVID-19 in a gender equality paradise[END_REF]. Mothers in the present study seem to confirm this imbalance in cooking duties. Alternatively, it is also possible that mothers felt a higher pressure to provide a variety of meals and meals of high nutritional standards than fathers, as women generally focus on providing healthy food to the family while men focus more on food pleasure when providing food [START_REF] Dupuy | La division sexuelle du travail alimentaire: qu'est-ce qui change?[END_REF].

Second, contrasts and ambivalences were observed regarding food pleasure. Many parents highlighted positive aspects of food pleasure during the lockdown, with a focus on the sensory dimension (pleasure from food sensory properties) and the interpersonal dimension of food pleasure (pleasure from interactions with others while cooking or eating and sharing food) [START_REF] Marty | Learned pleasure from eating: An opportunity to promote healthy eating in children?[END_REF]. In contrast, many parents also described a higher consumption of "pleasurable food" as negative during the lockdown. There were parents who only reported one side of food pleasure (the positive or the negative side), while other parents reported both sides: either when answering to the different questions, or embedded in one single answer. This seems to indicate that some parents struggled to find a balance between pleasure and "too much" pleasure during the lockdown, and this was related almost exclusively to the choice of palatable food and the amount and frequency of consumption. Even though food pleasure has a central role in the French eating culture [START_REF] Ducrot | Adherence to the French Eating Model is inversely associated with overweight and obesity: results from a large sample of French adults[END_REF], parents seem to know (and have internalized) the guidelines of the French National Nutrition Programme (PNNS, 2019) about healthy eating (e.g., avoid snacking, limit foods high in sugar and fat, limit alcohol, etc.) and realize their (family's) eating behaviour did not fully comply with these guidelines during the lockdown. Some answers seemed to indicate that parents themselves did not perceive their experienced food pleasure as negative in se, but that norms and recommendation prescribe that too much food pleasure is or can be a negative thing. This could be cause for concern, because it could make parents feel guilty about their food pleasure, while food pleasure is not necessarily a bad thing. A recent systematic literature review [START_REF] Ck9zg7q Bédard | Can eating pleasure be a lever for healthy eating? A systematic scoping review of eating pleasure and its links with dietary behaviors and health[END_REF] concluded, for example, that eating pleasure may be a levier for the promotion of healthy eating, and found especially favourable associations between eating pleasure and dietary outcomes. The review identified some strategies related to food pleasure as particularly promising: those that focus on sensory experiences, cooking and/or sharing activities, mindful eating, and memories associated with eating. In the same vein, a recent experimental study has shown that a pleasure-oriented intervention can increase the link between food liking and perceived healthiness in motherchild dyads, meaning that healthy foods were more appreciated after the intervention [START_REF] Poquet | Effect of a pleasure-oriented intervention on the nutritional quality of midafternoon snacks and on the relationship between food liking and perceived healthiness within mother-child dyads[END_REF].

It is also remarkable that those parents who described an increased temptation and desire to eat during the lockdown were almost exclusively mothers. Even though these mothers described an increased temptation for both themselves, their child, or their family in general, it seems to indicate that they struggled more with how to act upon food temptations or sensations of hunger. Mothers acknowledged the temptation but did not necessarily want to give in to it, they tried to control themselves, if possible. This might be due to gender differences in perceptions of desirable body shapes and related norms. A comparative study including 13 countries and 4 continents [START_REF] Robineau | Les normes de minceur: une comparaison internationale[END_REF] showed that the mean difference in BMI between men and women was largest in France, and that slimness is highly valued for French women (53%) but not for men (37%). The majority of French respondents prefer a slim female (52%) and a larger-sized male (62%), showing that the ideals related to body shape are very different for men and women. Third, several parents described that their emotions during the lockdown had an impact on their family's eating behaviour. In most cases, negative emotions (e.g., stress, boredom) were linked to a higher food intake and parents explained that foods could serve as a way to keep them busy or to comfort them in these difficult times. In contrast, some parents also described that their emotions lowered their appetite and induced weight loss. These findings could be interesting for health prevention during the ongoing pandemic. They seem to call for the need of strategies and initiatives that could help people to cope with their emotions during the lockdown, in order to avoid emotional under-and overeating which has been linked to unfavourable weight and health outcomes in the long term (e.g., Frayn & Knäuper, 2018). Governments could, for example, invest in accessible and affordable mental health care, and introduce preventive mental health campaigns.

Fourth, many parents wished to maintain positive changes in their family's behaviours, such as buying more local, seasonal, fresh foods, preparing more home-made meals, cooking with the family and taking more time to eat together. These intentions can only be encouraged. Children's involvement in cooking activities has, for example, been found to increase their food acceptance and intake of vegetables [START_REF] Allirot | Involving children in cooking activities: A potential strategy for directing food choices toward novel foods containing vegetables[END_REF][START_REF] Cunningham-Sabo | Cooking with Kids positively affects fourth graders' vegetable preferences and attitudes and self-efficacy for food and cooking[END_REF][START_REF] Jarpe-Ratner | An Experiential Cooking and Nutrition Education Program Increases Cooking Self-Efficacy and Vegetable Consumption in Children in Grades 3-8[END_REF], which was also expressed by some parents in this study. Children are also more likely to eat and try foods when they see their parents eat and enjoy the same foods [START_REF] Addessi | Specific social influences on the acceptance of novel foods in 2-5-year-old children[END_REF]. Moreover, more frequent family meals have been associated with a decreased risk of obesity [START_REF] Berge | The protective role of family meals for youth obesity: 10-year longitudinal associations[END_REF], and improved well-being [START_REF] Musick | Assessing causality and persistence in associations between family dinners and adolescent well-being[END_REF], even though this may also be due to different underlying factors.

Furthermore, frequent consumption of home prepared meals has been associated with better dietary quality and with lower adiposity (e.g., [START_REF] Mills | Frequency of eating home cooked meals and potential benefits for diet and health: cross-sectional analysis of a population-based cohort study[END_REF].

Parents' intentions stand, however, in contrast with an expressed doubt about the feasibility of the maintenance of these new eating and cooking habits. Time and a difficult work-life balance were mentioned as the most important barriers. Previous research has shown that employment and longer working days are associated with less time spent at cooking at home, especially among women (e.g., [START_REF] Adams | Prevalence and socio-demographic correlates of time spent cooking by adults in the 2005 UK time use survey[END_REF][START_REF] Etilé | Women's employment and the decline of home cooking: Evidence from France, 1985-2010[END_REF][START_REF] Sliwa | Maternal employment, acculturation, and time spent in food-related behaviors among Hispanic mothers in the United States. Evidence from the American Time Use Survey[END_REF]. Before the lockdown, working from home was not a common practice in France [START_REF] Aguilera | Home-based telework in France: Characteristics, barriers and perspectives[END_REF], it is therefore possible that the ongoing pandemic and its predicted related long-lasting effects on work culture [START_REF] Carillo | Adjusting to epidemic-induced telework: empirical insights from teleworkers in France[END_REF]) could be a window of opportunity for parents to use the time gain from a reduction in occupational commuting for cooking homemade meals and cooking with the family on days they are working from home. However, more research is needed to explore this, as surprisingly few significant differences between parents' reported experiences based on their work status were found in this study.

Furthermore, the current study has not done a follow-up on the participants and was thus unable to verify whether parents were able to fulfil their expressed intentions. As the pandemic is still ongoing, it could be interesting to do a follow-up after the pandemic, to examine possible long-lasting effects on families' eating and cooking habits.

Lastly, we also want to note that, just as for parents' work status, surprisingly few significant differences in parental experiences were found based on their perceived financial situation. Interestingly, however, the analysis did show that fewer parents with a comfortable financial status reported negative changes during the lockdown, compared to those parents with a difficult financial situation. This could reinforce the idea that these last people could be more vulnerable for negative experiences during a pandemic.

Strengths and limitations

Some limitations must be noted for this study. First, as this study is part of a mixed-method study, it is possible that parents were influenced by the content of closed-ended questions

preceding the three open-ended questions. These questions were for example about changes in the preparation of home-made food during the lockdown, the time spent cooking with the child, changes in parental motivations when buying food for the child et cetera (for a detailed overview: see [START_REF] Philippe | Child eating behaviors, parental feeding practices and food shopping motivations during the COVID-19 lockdown in France: (how) did they change?[END_REF]. However, even though some content of closed-ended questions was also present in parents' answers to the open-ended questions, these last questions also allowed for the emergence of new topics (e.g., the transmission of food-related values and skills, the burden of cooking more meals, problems linked to grocery shopping). In

addition, the open-ended questions gave parents the opportunity to express their personal experiences with food-related changes and to evaluate positive and negative aspects and future goals. Second, even though this study had a diverse French sample, it was not entirely representative. There was, for example, only a limited percentage of parents with a lower level of education (33.5% in this sample compared to approximately 55% in the French population (Insee, 2016)). Experiences and perceptions of parents with a higher level of education might thus be overrepresented in the current study. This is important to keep in mind, as level of education is linked to attitudes towards healthy eating and to compliance with dietary guidelines [START_REF] Lê | Attitudes toward healthy eating: a mediator of the educational level-diet relationship[END_REF].

This study also presents several strengths. A first strength is the large sample size (N=498) which enabled the researchers to obtain insight into parents' positive and negative foodrelated experiences during the first COVID-19 lockdown in France. The use of NVivo made it possible to code the high number of answers to the open-ended questions without losing the overview and to keep track of more or less dominant themes and subthemes. This study showed that the use of open-ended questions could be an interesting method for obtaining qualitative data from a high number of participants and for generating valuable results that can complement those obtained with closed-ended questions. In this study, the results provided valuable insight into the drivers and barriers for changes in families' behaviours, even beyond the scope of COVID-19. For example, parents' and children's emotions during the lockdown and spending more time at home seemed to have strongly supported changes in families' eating and cooking behaviours. These results are useful to consider when promoting healthy eating behaviours in families. Then, despite the fact that this study had an unbalanced sample of mothers (N=357, 72%) and fathers (N=141, 28%) which is not preferable when comparing groups, the quite high number of fathers could be considered as a second strength, especially knowing that the inclusion of fathers in feeding research can be challenging (e.g., [START_REF] Jansen | Acceptability and accessibility of child nutrition interventions: fathers' perspectives from survey and interview studies[END_REF]. Moreover, despite this unbalanced sample significant differences were found using matrix coding and Chi-squared tests; they generated insight into gender differences regarding perceptions, experiences and emotions. These results, and to a lesser extent those based on perceived financial situation and work status, showed that experiences can differ during a situation such as a pandemic. Policy makers should be aware of this and strive to support all groups in the population in the best possible way.

Conclusion and perspectives

This study revealed intimate perceptions of parents about changes in their families' eating, cooking and food-shopping habits during the first COVID-19 lockdown in France. The results uncovered positive and negative experiences, and many contrasts and ambivalences. Time was identified by parents as a cornerstone for changes in eating and cooking behaviours, and as a future barrier to maintain the positive changes. The COVID-19 situation and related measures were unseen in France and probably amplified certain experiences, contrasts and ambivalences which were already present, but to a lesser extent. The results of this study might be of interest for further research studying possible facilitators and barriers for the adoption of recommended eating, cooking and food shopping behaviours in families, beyond the pandemic, and for intervention studies. Some interesting gender differences were also uncovered in the current study, stressing the importance of studying perceptions and behaviours of both men and women separately in future studies and to consider possible

(

  +): "More convivial meals, pleasure of cooking with the children and all of this will create great memories." (-): "Weight gain, too much comfort food." (+): "More time, more pleasure, more diversity, new recipes (especially from Cyril Lignac's tv programme (a French tv-cook))." (-): "We are getting fatter." (+): "I take more time to cook and please my family, I buy more locally and things that tempt us." (-): "We eat more however than before." (+): "I have cooked more home-made mid-afternoon snacks, before I only bought them." (-): "We have eaten a lot fattier, a lot more pleasure foods, us adults have taken to mid-afternoon snacking too." (M): "Making more homemade mid-afternoon snacks."

  Frayn, M., & Knäuper, B. (2018). Emotional eating and weight in adults: a review. Current Psychology, 37(4), 924-933. https://doi.org/10.1007/s12144-017-9577-9 GEM-RCN (2015). Recommandation nutrition du groupe d'étude des marchés de restauration collective et nutrition. Retrieved from

Table 1 .

 1 Parents' characteristics.Note. Table retrieved from[START_REF] Philippe | Child eating behaviors, parental feeding practices and food shopping motivations during the COVID-19 lockdown in France: (how) did they change?[END_REF]

	Characteristic

Table 2 .

 2 Number and percentage of parents (total N = 498) describing content belonging to themes and

Theme and subtheme Positive experiences Negative experiences

						Aspects to
						maintain
		N	%	N	%	N	%
	Nothing/ No change	53	10.6	129	25.9	98	19.7
	Time	110	22.1	11	2.2	45	9.0
	Food choice
	Sustainable foods	58	11.6	4	0.8	75	15.1
	Healthy/ fresh foods	106	21.3	17	3.4	97	19.5
	Unhealthy/ palatable foods	23	4.6	111	22.3	11	2.2
	Quality foods and meals	18	3.6	1	0.2	11	2.2
	Meat and fish	5	1.0	3	0.6	5	1.0
	Alcohol	0	0.0	7	1.4	0	0.0
	Bread	14	2.8	4	0.8	5	1.0
	Nutrition, diversity, balance	33	6.6	19	3.8	24	4.8
	Foods easy to store for longer	0	0.0	2	0.4	2	0.4
	Food preparation
	Sociability (cook together)	116	23.3	1	0.2	73	14.7
	Home-made dishes	103	20.7	18	3.6	87	17.5
	Elaborated dishes	16	3.2	3	0.6	5	1.0
	Recipes	55	11.0	31	6.2	30	6.0
	Quickly prepared dishes	0	0.0	5	1.0	0	0.0
	Unspecified a	46	9.2	0	0.0	46	9.2
	Commensality (eat together, sharing)	52	10.4	3	0.6	38	7.6
	Emotions/ meal atmosphere	28	5.6	30	6.0	0	0.0
	Education, transmission	22	4.4	0	0.0	4	0.8
	Control intake child	4	0.8	0	0.0	0	0.0
	Food acceptation/ rejection child	13	2.6	1	0.2	5	1.0
	Frequency/ quantity
	Frequency meals	6	1.2	64	12.9	6	1.2
	Quantity consumed	8	1.6	41	8.2	5	1.0
	Desire, temptation to eat/ appetite	1	0.2	48	9.6	13	2.6
	Food pleasure	32	6.4	7	1.4	11	2.2
	Health	17	3.4	4	0.8	16	3.2
	Weight, calories, lack of sport	5	1.0	36	7.2	0	0.0
	Meal planning	10	2.0	0	0.0	10	2.0
	Meal timing	1	0.2	16	3.2	7	1.4
	Meal location	0	0.0	1	0.2	3	0.6
	Food shopping	13	2.6	37	7.4	10	2.0
	Finances, prices	3	0.6	35	7.0	4	0.8
	Food waste	4	0.8	0	0.0	5	1.0
	Decorations	1	0.2	0	0.0	1	0.2
	Cleaning/ Tidying	2	0.4	2	0.4	0	0.0
	Easter	0	0.0	5

Table 3 .

 3 Percentages of mothers (M) and percentages of fathers (F) describing content belonging to themes and subthemes for each of the three open-ended questions. Percentages of mothers are calculated in proportion to total number of mothers (N=357), and percentages of fathers are calculated in proportion to total number of fathers (N=141).

	Theme and subtheme	Positive experiences	Negative experiences	Aspects to maintain
		M (%)		F (%)	M (%)		F (%)	M (%)		F (%)
	Nothing/ No change	10.80		10.50	21.65	*** 37.06	19.94		19.58
	Time	22.22		22.38	2.85		0.70	9.40		8.39
	Food choice
	Sustainable foods	11.39		12.59	0.57		1.40	13.39	*	19.58
	Healthy/ fresh foods	21.37		21.68	3.42		3.50	18.23		23.08
	Unhealthy/ palatable foods	4.84		4.20	23.36		20.28	2.28		2.10
	Quality foods and meals	2.84		5.59	0		0.70	1.42	*	4.20
	Meat and fish	0.57		2.10	0.28		1.40	0.57		2.10
	Alcohol	0		0	0.57		2.10	0		0
	Bread	3.10		2.10	0.85		0.70	0.85		1.40
	Nutrition, diversity, balance	6.26		7.69	3.70		4.20	4.56		5.60
	Foods easy to store for longer	0		0	0.28		0.70	0.28		0.70
	Food preparation
	Sociability (cook together)	24.50		21.00	0.28		0	16.52	*	10.49
	Homemade dishes	23.08	*	15.38	4.48	**	0.70	17.95		16.78
	Elaborated dishes	3.11		3.50	0.85		0	0.85		1.40
	Recipes	13.68	**	5.59	7.69	**	2.80	7.12		3.50
	Quickly prepared dishes	0		0	1.42		0	0		0
	Unspecified a	9.11		9.79	4.56	*	1.40	11.40	*	4.20
	Commensality	11.11		9.09	0.28		0	9.40	**	3.50
	(eat together, sharing)
	Emotions/ meal atmosphere	5.70		5.59	6.55		4.20	2.56		2.80
	Education, transmission	5.13		2.80	0		0	0.85		0.70
	Control intake child	0.85		0.70	0		0	0		0
	Food acceptation/ rejection	3.10		1.40	0		0.70	1.14		0.70
	child
	Frequency/ quantity
	Frequency meals	0.85		2.10	13.11		12.59	1.14		1.40
	Quantity consumed	1.13		2.80	8.83		7.70	0.85		1.40
	Desire, temptation to eat/	0		0	12.82	***	2.10	0		0
	appetite
	Food pleasure	5.98		7.69	1.14		2.10	2.28		2.10
	Health	3.42		3.50	0.85		0.70	3.13		3.50
	Weight, calories, lack of sport	1.13		0.70	6.84		8.39	0		0
	Meal planning	1.99		2.10	0		0	0		0
	Meal timing	0.28		0	3.99		1.40	1.14		2.10
	Meal location	0		0	0		0.70	0.85		0
	Food shopping	2.28		3.50	7.98		6.30	1.99		2.10
	Finances, prices	0.28		1.40	7.41		6.30	0.28		2.10
	Food waste	1.13		0	0		0	0.85		1.40
	Decorations	0.28		0	0		0	0.28		0
	Cleaning/ Tidying	0.28		0.70	0.28		0.70	0		0
	Easter	0		0	1.14		0.70	0		0
	a

subthemes for each of the three open-ended questions.

food choice, food preparation, sociability and commensality, food pleasure, emotions/ meal

atmosphere, and education/ transmission.

Acknowledgements

The authors would like to thank the independent ethical committee Inserm for accepting to review their study protocol in a very limited time span. They also thank the participants for their interest in the study.

Funding sources

This work was supported by the European Union's horizon 2020 research and innovation program (Marie Sklodowska-Curie grant agreement No 764985: EDULIA project).

differences in interventions. Here, it is however recommended to recruit balanced samples of men and women, in order to study possible gender differences more precisely.

Authors Contributions

KP, SM-P and SI conceptualized the study. KP and SMP conducted all analyses, SI was involved in the final steps of the analyses. KP is first author and wrote a first version of the manuscript, thereafter all authors contributed to editing the manuscript and they all approved the final article.