Relative Validity of a Diet History Questionnaire Against a Four-Day Weighed Food Record among Older Men in Australia: The Concord Health and Ageing in Men Project (CHAMP).

ABSTRACT

OBJECTIVES: To evaluate the relative validity of the diet history questionnaire (DHQ) used in the Concord Health and Ageing in Men Project (CHAMP) against a four-day weighed food record (4dWFR) as the reference method. DESIGN AND MEASUREMENTS Detailed DHQ followed by a 4dWFR were completed between July 2012 and October of 2013. SETTING: Burwood, Canada Bay and Strathfield in Sydney, Australia. PARTICIPANTS: Fifty six community- dwelling men aged 75 years and over (mean=79 years). RESULTS: DHQ estimates of intakes were generally higher than estimates from 4dWFR. Differences between the two methods were generally less than 20% with the exception of ß-carotene (37%). Fixed and proportional biases were only present for retinol, ß-carotene, magnesium, phosphorus and percentage of energy from protein; however, 95% limits of agreement were in some cases wide. Pearson correlation coefficient of log-transformed unadjusted values ranged from 0.15 (zinc) to 0.70 (alcohol), and from 0.06 (iron) to 0.63 (thiamin) after energy-adjustment. Spearman's correlation coefficients ranged from 0.16 (zinc) to 0.80 (alcohol) before energy adjustment, and from 0.15(zinc) to 0.81(alcohol) after energy adjustment. CONCLUSION: Our findings suggest that the DHQ used in CHAMP to measure the nutritional intake of its participants is appropriate to this age group and provides reasonably similar results to the 4dWFR for the majority of nutrients analysed.