Psychosocial predictors of energy underreporting in a large doubly labeled water study.
BACKGROUND
Underreporting of energy intake is associated with self-reported diet measures and appears to be selective according to personal characteristics. Doubly labeled water is an unbiased reference biomarker for energy intake that may be used to assess underreporting.


OBJECTIVE
Our objective was to determine which factors are associated with underreporting of energy intake on food-frequency questionnaires (FFQs) and 24-h dietary recalls (24HRs).


METHODS
The study participants were 484 men and women aged 40-69 y who resided in Montgomery County, MD. Using the doubly labeled water method to measure total energy expenditure, we considered numerous psychosocial, lifestyle, and sociodemographic factors in multiple logistic regression models for prediction of the probability of underreporting on the FFQ and 24HR.


RESULTS
In the FFQ models, fear of negative evaluation, weight-loss history, and percentage of energy from fat were the best predictors of underreporting in women (R(2) = 0.09); body mass index, comparison of activity level with that of others of the same sex and age, and eating frequency were the best predictors in men (R(2) = 0.10). In the 24HR models, social desirability, fear of negative evaluation, body mass index, percentage of energy from fat, usual activity, and variability in number of meals per day were the best predictors of underreporting in women (R(2) = 0.22); social desirability, dietary restraint, body mass index, eating frequency, dieting history, and education were the best predictors in men (R(2) = 0.25).


CONCLUSIONS
Although the final models were significantly related to underreporting on both the FFQ and the 24HR, the amount of variation explained by these models was relatively low, especially for the FFQ.
Tooze
Janet A
JA
Cancer Prevention Fellowship Program, National Cancer Institute, Executive Plaza North, Suite 3131, 6130 Executive Boulevard, MSC 7354, Bethesda, MD 20892-7354, USA. toozej@mail.nih.gov
Subar
Amy F
AF
Thompson
Frances E
FE
Troiano
Richard
R
Schatzkin
Arthur
A
Kipnis
Victor
V
D000328:Adult; D000368:Aged; D001828:Body Image; D015992:Body Mass Index; D001834:Body Water / Q000378:metabolism; D004032:Diet / Q000523:psychology; D004034:Diet Surveys; D004041:Dietary Fats / Q000008:administration & dosage*; D002149:Energy Intake; D004734:Energy Metabolism; D015444:Exercise; D005260:Female; D006801:Humans; D008019:Life Style; D016015:Logistic Models; D008297:Male; D008396:Maryland; D011939:Mental Recall; D008875:Middle Aged; D010552:Personality Assessment; D012650:Self Disclosure; D012737:Sex Factors; D012928:Social Desirability; D011795:Surveys and Questionnaires
D004041:Dietary Fats