Relative validity and reproducibility of dietary quality scores from a short diet screener in a multi-ethnic Asian population

Abstract Objective Short screeners for assessing dietary quality are lacking in Asia. We recently developed a short thirty-seven-item diet screener (DS). The present study aimed to evaluate reproducibility and relative validity of the DS in assessing a priori dietary quality indices (DQI; i.e. the Alternative Healthy Eating Index-2010 (AHEI-2010), alternate Mediterranean Diet (aMed) and Dietary Approaches to Stop Hypertension (DASH) diet) and intakes of selected foods. Design DS administration and biomarker measurement took place twice within a 4-month interval. A 163-item FFQ was administered one month after the second DS administration. Setting Singapore, a multi-ethnic urban Asian country. Subjects Singapore residents (n 161) aged 18–79 years, of Chinese, Malay and Indian ethnicity. Results Reproducibility coefficients for the two DS were 0·71 (DQI) and 0·65 (food groups). Correlations (ρ) between mean DS and FFQ DQI scores were 0·51 (AHEI-2010), 0·50 (aMed) and 0·61 (DASH; all P<0·05). Cohen’s weighted kappa indicated moderate agreement between the two measures (κ w=0·48–0·58). DS DQI scores were associated with concentrations of β-cryptoxanthin (AHEI-2010, ρ=0·26; P<0·05), odd-chain SFA (aMed, ρ=0·24; DASH, ρ=0·25; both P<0·05), and enterolactone, total carotenoids, PUFA and α-linolenic acid (all scores, ρ=0·17–0·30; all P<0·05). Scores were not associated with isoflavone or long-chain n-3 PUFA concentrations. Conclusions A short screener can be used to assess DQI with good reproducibility and relative validity compared with a longer FFQ in an Asian population.