Influência da desejabilidade social na Estimativa da ingestão alimentar Obtida através de um questionário de Frequência de consumo alimentar

Abstract

Introduction: Self-report of dietary intake could be biased by social desirability thusaffecting risk estimates in epidemiological studies. The objective of this study was toassess the effect of social desirability on dietary intake estimated from a food frequencyquestionnaire (FFQ). Methods: A convenience sample of 483 Portuguese universitystudents was recruited. Subjects were invited to complete a two-part self-administeredquestionnaire: the first part included the Marlowe-Crowne Social Desirability Scale(M-CSDS), a physical activity questionnaire and self-reported height and weight; thesecond part, included a semi-quantitative FFQ validated for Portuguese adults, thatshould be returned after fulfilment. All subjects completed the first part of thequestionnaire and 40.4% returned the FFQ fairly completed. Results: In multipleregression analysis, after adjustment for energy and confounders, social desirabilityproduced a significant positive effect in the estimates of dietary fibre, vitamin C, vitaminE, magnesium and potassium, in both genders. In multiple regression, after adjustmentfor energy and confounders, social desirability had a significant positive effect in theestimates of vegetable consumption, for both genders, and a negative effect in whitebread and beer, for women. Conclusion: Social desirability affected nutritional and foodintake estimated from a food frequency questionnaire.