Development of a Short Questionnaire to Assess Diet Quality among Older Community-Dwelling Adults.

OBJECTIVE: To evaluate the use of a short questionnaire to assess diet quality in older adults. DESIGN: Cross-sectional study. SETTING: Hertfordshire, UK. PARTICIPANTS: 3217 community-dwelling older adults (59-73 years). MEASUREMENTS: Diet was assessed using an administered food frequency questionnaire (FFQ); two measures of diet quality were defined by calculating participants' 'prudent diet' scores, firstly from a principal component analysis of the data from the full FFQ (129 items) and, secondly, from a short version of the FFQ (including 24 indicator foods). Scores calculated from the full and short FFQ were compared with nutrient intake and blood concentrations of vitamin C and lipids. RESULTS: Prudent diet scores calculated from the full FFQ and short FFQ were highly correlated (0.912 in men, 0.904 in women). The pattern of associations between nutrient intake (full FFQ) and diet scores calculated using the short and full FFQs were very similar, both for men and women. Prudent diet scores calculated from the full and short FFQs also showed comparable patterns of association with blood measurements: in men and women, both scores were positively associated with plasma vitamin C concentration and serum HDL; in women, an inverse association with serum triglycerides was also observed. CONCLUSIONS: A short food-based questionnaire provides useful information about the diet quality of older adults. This simple tool does not require nutrient analysis, and has the potential to be of value to non-specialist researchers.