The aim of this thesis was to evaluate the level of feeding habits of a selected human population segment in order to assess their understanding of issues related to nutrition and to basic components in their diet. For this purpose, a measuring instrument (a questionnaire) was designed. The first part contained questions related to respondent´s eating habits preferences, while the second part of questionnaire included questions examining the level of respondent?s nutritional awareness. In total 389 questionnaires were personally administered and completed by the respondents, under supervision of teachers. On the basis of the recorded answers it was found that, when purchasing food, the interviewed persons are governed mostly by the quality of it (37%). It was also discovered that, 40% of people preferred local foods to foods from abroad. Only 13% of respondents indicated their ?always or almost always? preference for ?bio foods?. It may also be said that, the three most popular dairy products are yoghurts (80%), milk (72%) and cheeses (72%), as opposed to fermented drinks (43%), which are the least consumed dairy products. Among the most popular meats the respondents included these three categories: chicken (83%), pork (73%) and beef (47%). The least favourite meat selected by respondents was mutton and lamb (35%). It was found that, 27% of the respondents follow information presented on food packaging but also that, 16% of the respondents do not follow packaging data, at all. According to the recorded frequency of occurrence the sum of correct answers can be said that most students answer 4 questions correctly. The recorded answer frequency counts show that most respondents answered correctly the following question: "What is bio food?" (94% of respondents). The worst answered individual question had to do with choosing foods with the highest ?Vitamin C? content, with only 7% being correct. On the basis of recorded answers it may be concluded that; the food consumption was influenced by the type of school which the respondents attended; as it appears related to the respondents´ age and their individual ability to decide on their food money spending. The questions that examined the level of information have shown that, the overall percentage of correct answers was increasing depending on the age of a respondent. The total percentage of correct answers kept increasing in relation to increasing age of respondents. No influence of gender on percentage totals of correct responses was demonstrated.

Contexte : L'absence d'un ensemble de valeurs permettant le calcul d’années de vie ajustées par la qualité (AVAQ) est une limite importante lorsqu'il s'agit d'établir la valeur des traitements émergents pour traiter l'allergie alimentaire. Pour être valables, les AVAQ doivent être calculées à partir de questionnaires adaptés à la population cible en raison des déficits et des préférences variables selon les populations et les maladies, ce qui n'était pas le cas dans les études précédentes en allergie alimentaire. L'objectif de cette étude était d'établir un ensemble de valeurs de préférence pour le questionnaire générique SF-6Dv2 pour le calcul de l'utilité dans la population canadienne atteinte d'allergies alimentaires. Méthodes : Deux cent quatre-vingt-quinze parents de patients âgés de 0 à 17 ans et 154 patients âgés de 12 ans et plus atteints d'allergie(s) alimentaire(s) ont été recrutés en clinique et en ligne. Les participants ont été sollicités à remplir un questionnaire en ligne autoadministré comprenant des questionnaires génériques de qualité de vie reliée à la santé. Différents états de santé décrits par le SF-6Dv2 ont été évalués à l'aide d'exercices d’arbitrage temporel et de choix expérimentaux discrets. Les données issues de ces techniques d'élicitation ont été combinées à l'aide du modèle de régression hybride. Résultats : Deux cent quarante et un parents et 125 patients ont réalisé 3904 exercices d’arbitrage temporel et 5112 choix expérimentaux discrets. La désutilité a été estimée pour chaque niveau de chaque dimension du SF-6Dv2. Les valeurs d'utilité calculées à partir de l’ensemble de valeurs de préférences établi étaient en moyenne inférieures de 0,15 (IC à 95 %: 0,12-0,18) et corrélaient faiblement (R2=0,46) avec celles dérivées du questionnaire générique EQ-5D-5L dans la même cohorte. Conclusion : Un ensemble de valeurs de préférence représentatif des patients et familles atteints d'allergies alimentaires a été déterminé à partir du questionnaire générique SF-6Dv2. Cet ensemble de valeurs de préférence adapté contribuera à améliorer la validité des futures estimations d'utilité dans cette population pour l'évaluation des traitements émergents ayant potentiellement un impact sur la qualité de vie reliée à la santé, mais étant parfois coûteux. / Background: The lack of a value set allowing the calculation of quality-adjusted life-years (QALY) is an important limitation when establishing the value of emerging therapies to treat food allergy. To be valid, QALYs must be calculated from questionnaires adapted to the target population because of varying deficits and preferences across populations and diseases, which was not the case in previous studies. This study aimed to develop a Short-Form Six-Dimension version 2 (SF-6Dv2) preference value set for the calculation of health utilities from the Canadian food allergic population. Methods: Two hundred ninety-five parents of patients aged 0-17 years old and 154 patients aged 12 years old and above with food allergy were recruited in the clinic and online. Participants were asked to complete a self-administered online questionnaire including generic health-related quality of life questionnaires. Various health states described by the SF-6Dv2 were valued with time-trade-off and discrete choice experiments. Data from elicitation techniques were combined using the hybrid regression model. Results: A total of 241 parents and 125 patients performed 3904 time trade-off and 5112 discrete choice experiments. Utility decrements were estimated for each level of each SF-6Dv2 dimension. Utility values calculated based on the validated preference set were on average 0.15 lower (95% CI: 0.12-0.18) and were poorly correlated (R2=0.46) with those derived from the EQ-5D-5L generic questionnaire in the same cohort. Conclusion: A representative preference value set for patients with food allergy was determined using the SF-6Dv2 generic questionnaire. This adapted preference value set will contribute to improve the validity of future utility estimates in this population for the appraisal of upcoming potentially impactful but sometimes costly therapies.