Gender differences in social desirability and approval biases, and associations with diet quality in young adults.

Social desirability and approval biases can influence self-report of diet, contributing to inaccurate assessment. Biases may be influenced by sex. This study examined gender differences in social desirability and approval, and diet quality in young adults, and relationships between social biases and diet quality. Data from 1003 young adults participating in the Advice, Ideas and Motivation for My Eating trial, median age 21.7 years, BMI 24.7 kg/m were included. Biases were measured using Marlowe-Crowne Social Desirability Scale Short-Form, Martin Larsen Approval Motivation Scale, and diet quality using the Australian Recommended Food Score. Pearson chi-square, t-test and Wilcoxon tests evaluated gender differences and Spearman's rank-order tested strengths of correlations between biases and diet quality. Social desirability did not differ by gender, however females reported higher social approval scores than males (p = 0.009). Among females, there was a positive correlation between social desirability and diet quality (p = 0.002), and between social approval and dairy sub-scale (p < 0.001); and a negative correlation between social approval and vegetable subscale (p = 0.045). Among males there were no correlations between social desirability or social approval and overall diet quality. Social approval may be more common in females and influence self-reported diet. To address bias and mis-reporting errors, future studies should account for participants' social desirability and/or social approval status, especially among young adult females. Further research is needed to explore gender differences in social desirability and approval in young adults, and associations between social biases and diet quality.