Validation of Dietary Intake Data in Black Women with Type 2 Diabetes

The validity of baseline dietary intake data in women participating in a culturally competent intervention study for black women with type 2 diabetes was assessed. The relationship of sociodemographic and physiologic factors with underreporting of dietary intake was determined. Criterion validity of dietary intake, which had been assessed using the Nutritionist Five Collection Form, a combination of a standard 2-day dietary recall and a modified, culturally appropriate food frequency questionnaire, was determined. Data were analyzed using First Data Bank Nutritionist Five (version 2.3, 2000, First Data Bank, San Bruno, CA) software. Validation of baseline dietary data in 109 women was performed by calculating the ratio of energy intake to resting metabolic rate. χ2 and t tests were used to assess relationships between underreporting and sociodemographic and physiologic factors. Mean ratio of energy intake to resting metabolic rate was 1.46 (±0.4). Using a lower limit of 1.35, the prevalence of underreporting was 46.8%. Underreporting was significantly associated with body mass index (P≤0.001) and waist circumference (P<0.001). Use of this combined dietary recall and modified food frequency questionnaire might, therefore, provide more accurate dietary assessment in this population. Additional modification and validity testing is warranted in this and other populations.