Kadınların Diyetle Demir, Folat ve B12 Vitamini Alım Durumlarının Değerlendirilmesine Yönelik Besin Tüketim Sıklığı Anketinin Geliştirilmesi

Abstract

The aim of this study is to develop a food frequency questionnaire that can assess women's intake of iron, folate, and vitamin B12 through diet. The developed questionnaire's validity is assessed using 24-hour dietary recall and biochemical parameters, and its reliability is evaluated using repeated applications. Initially, 445 non-pregnant volunteers aged 19-50 were included in the study. However, 25 participants were excluded from the study due to having a disease that could affect nutrition, on a special diet (gluten-free diet, vegetarian diet, weight loss diet, etc.), being noticed during the questionnaire application, or not completing the questionnaire. As a result, the research was concluded with 420 volunteer participants. The questionnaire, which includes individuals' general information, health status, 24-hour dietary recall, and the food frequency questionnaire developed to evaluate the iron, folate, and vitamin B12 content of the diet, was applied face-to-face. At this stage, the biochemical parameters of 100 individuals whose biochemical parameters had already been taken at the Hacettepe University Faculty of Medicine Department of Family Medicine Clinics were also taken and recorded. The correlation between the food frequency questionnaire and the 24-hour dietary recall was used for the validity assessment. As a result of this calculation, the relationship was found to be statistically significant for iron (mg) (r=0.210; p<0.001) and folate (µg) (r=0.208; p<0.001) but not for vitamin B12 (µg) (r=0.092; p=0.058). While the correlations between the dietary frequency questionnaire-calculated iron intake (mg) and serum ferritin (µg/L) (r=0.052; p=0.607) and between the dietary folate intake (µg) and serum folate (µg/L) (r=0.107; p=0.292) were not statistically significant, the correlation between the dietary vitamin B12 intake (µg) and serum vitamin B12 (ng/L) was found to be statistically significant (r=0.341; p=0.001). The Bland-Altman method showed statistical significance for consistency between the two methods for vitamin B12 (<0.001). The Bland-Altman coefficient was 0.318, indicating that the effect of this independent variable on the dependent variable was not due to random variation. The repeatability of all nutrients and food groups in the questionnaire was statistically significant (p<0.001). There is a statistically significant and strong relationship between the values of iron (r=0.846; p<0.001), folate (r=0.871; p<0.001), and vitamin B12 (r=0.762; p<0.001) in repeated dietary frequency questionnaires. The validity of the developed dietary frequency questionnaire for iron and folate was demonstrated through correlation analyses with 24-hour dietary recall. Additionally, the validity of this questionnaire for vitamin B12 was supported by correlations with biochemical parameters and the Bland-Altman graph. The correlations of repeated dietary frequency questionnaires demonstrate the reliability of the questionnaire.