Reliability and relative validity of short-food frequency questionnaire

Purpose The purpose of this paper is to describe reliability and relative validity of the short-food frequency questionnaire (SH-FFQ) used for assessing food groups and nutrient intakes of Iranian adults. Design/methodology/approach The food list used in the SH-FFQ was elaborated based on a dietary survey of a sample of 60 individuals aged between 15 and 65 years. A total of 180 subjects (93 males and 87 females) were included in the study. All participants completed two SH-FFQs with one month interval, a single 24 hours recall (24hR) and two food records for three non-consecutive days. Findings No significant differences were observed in the mean daily intakes of energy, food groups and most of the nutrients between the reference tools and the two semi-quantitative SH-FFQs ( p >0.05). The mean energy-adjusted reliability coefficients for all variables were 0.54 and 0.55 in men and women. The mean energy-adjusted and deattenuated correlation coefficients for all items between the SH-FFQ and reference tools were 0.54. Also, the mean percent misclassified into opposite quartiles for all food groups and nutrients was 12.6 percent. Originality/value The designed SH-FFQ developed for the Life style Promotion Project has reasonable reliability and relative validity for food groups and nutrient in Iranian adults.