Relationship between Consumption Frequency of “Grain Dishes,” “Fish and Meat Dishes,” and “Vegetable Dishes” Assessed by Dietary Photographs and a Self-administered Questionnaire among Female University Students

Abstract

Objective: Questionnaires assessing the consumption frequencies of ＂grain dishes,＂ ＂fish and meat dishes,＂ and ＂vegetable dishes＂ are often used to evaluate whether a participant＇s diet is nutritionally balanced.This study examined how accurately such questionnaires reflect actual consumption frequencies.Methods: A self-administered questionnaire assessing the typical consumption frequency of ＂grain dishes,＂ ＂fish and meat dishes,＂ and ＂vegetable dishes＂ were administered to 4th year female university students (n = 33), studying to become registered dietitians. Self-taken photographs of meals and snacks consumed during a seven-day period were also obtained from participants. Actual consumption frequencies of ＂grain dishes,＂ ＂fish and meat dishes,＂ and ＂vegetable dishes＂ were determined by examining dietary photographs. The correlation between self-reported food consumption and actual food consumption as measured by dietary photographs was examined, as were tendencies in under-and over-reporting of food consumption. Subsequently, participants were individually interviewed regarding any discrepancies between self-reported and actual food consumption frequencies during the seven-day period.Results: Participants showed a tendency to over-report rather than under-report consumption frequency in their questionnaire responses. This was especially true for ＂grain dishes.＂ Over-reporting was observed in 36.4% of participants. The reasons given by participants for this inconsistency were grouped into three categories: (1) difficulties in answering the questionnaire or in paying attention to what was eaten, (2) over-or under-estimation of what was eaten, and (3) inaccurate answers to the questionnaire. Conclusions:Participants tended to over-report food consumption in their questionnaire responses.Results of this study suggest that self-report measures do not accurately reflect actual consumption frequencies of ＂grain dishes,＂ ＂fish and meat dishes,＂ and ＂vegetable dishes.＂ Jpn. J. Nutr. Diet., 74 (6) 182～190 (2016)