Development and validation of a semi-quantitative food frequency questionnaire to assess dietary intake in Turkish adults

Objectives: to validate the original food frequency questionnaire in turkish adult population. methods: the cross-sectional study was conducted in june and december 2008 and 2009,and comprised adults of either gender aged 30-70 years. all subjects were caucasians and were native turkish speakers. the food frequency questionnaire containing 229 most frequently consumed foods under 7 topics was used for data collection. it was completed twice and the 24-hour dietary recall four times in a year. in order to assess the validity of the questionnaire,pearson correlation,attenuation coefficient,measures of agreement between the two methods,weighted kappa statistics and bland-altman plots were employed. spss 16 was used for statistical analysis. results: of the 120 subjects in the study,71(59%) were males and 49(41%) were females with an overall mean age of 50.16±9.76 years. the correlation of estimated nutrient intake between the food frequency questionnaire and 24hour dietary recall varied between 0.200 and 0.468,energy-adjusted regression was between 0.044 and 0.611 and attenuation coefficients of regression were between 0.339 and 0.658 for the selected macro and micro nutrients. bland-altman plots showed an acceptable agreement between the two methods. when nutrient intake was categorised in quartiles,proportions of the same or adjacent quartiles were 98.3%,98.4%,98.3%,96.7% and 95% for energy,fat,protein,carbohydrates and fibre,respectively. conclusion: the first food frequency questionnaire developed in turkish language was an adequate and valid tool to assess the nutritional habits of the local population. © 2015,pakistan medical association. all rights reserved.