Leveraging questionnaire-based physical activity levels (PAL) to identify energy intake misreporting in the Goldberg method: A doubly-labeled water validation study

The Goldberg method has been suggested for identifying energy intake (EI) under-reporting in nutritional epidemiology. Its implementation, however, is limited by challenges associated with estimating physical activity levels (PAL). We quantified the accuracy of the Sedentary Time and Activity Reporting Questionnaire (STAR-Q) derived PAL (PALSTAR-Q) combined with the Goldberg method (Goldberg-PALSTARQ) to identify EI misreporting as compared with doubly labeled water (DLW) derived total energy expenditure (TEEDLW). Between 2009 and 2011, 99 men and women completed a two-week DLW protocol, a food frequency questionnaire, and the STAR-Q. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of the Goldberg-PALSTAR-Q were determined. Fifty-eight percent of men and women were classified as under-reporters by Goldberg-PALSTAR-Q compared with 60% of men and 56% of women by TEEDLW. Among men, sensitivity, specificity, PPV, NPV and accuracy and 95% confidence intervals were 88% (68%-97%), 87% (61%-98%), 91% (72%-99%), 81% (56%-94%), and 87% (72%-95%), respectively; and among women 79% (62%-90%), 69% (50%-84%), 77% (60%-88%), 72% (52%-86%), and 75% (62%-84%), respectively. Validated individual level PALs used with the Goldberg method can be informative in sensitivity analyses to gain insight into EI misreporting in nutritional epidemiology studies lacking in objective EI measures.