title: Social desirability trait influences on self-reported dietary measures among diverse participants in a multicenter multiple risk factor trial.
abstract: Data collected at 4 Behavioral Change Consortium sites were used to assess social desirability bias in self-reports derived from a dietary fat screener (PFat), a dietary fruit and vegetable screener (FVS), and a 1-item question on fruit and vegetable intake. Comparisons were made with mean intakes derived from up to 3 24-h recall interviews at baseline and follow-up (at 12 mo in 3 sites, 6 mo in the fourth). A social-desirability-related underestimate in fat intake on the PFat relative to the 24HR (percentage energy as fat) was evident in women [baseline b = -0.56 (P = 0.005); follow-up b = -0.62 (P < 0.001)]. There was an overestimate in FVS-derived fruit and vegetable consumption (servings/week) in men enrolled in any intervention at follow-up (b = 0.39, P = 0.05) vs. baseline (b = 0.04, P = 0.75). The 1-item fruit and vegetable question was associated with an overestimate at baseline in men according to SD score (b = 0.14, P = 0.02), especially men with less than college education (b = 0.23, P = 0.01). Women with less than college education expressed a similar bias at follow-up (b = 0.13, P = 0.02). Differences in the magnitude of bias according to gender, type of instrument used, and randomization condition are comparable to what has been seen for other instruments and have important implications for both measuring change in studies of diet and health outcomes and for developing methods to control for such biases.
authors.affiliation: South Carolina Statewide Cancer Prevention and Control Program, Department of Epidemiology and Biostatistics, Arnold School of Public Health University of South Carolina, Columbia, SC 29208, USA. jhebert@sc.edu
authors.forename: James R
authors.initials: JR
authors.lastname: Hebert
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Hurley
authors.forename: Karen E
authors.initials: KE
authors.lastname: Peterson
authors.forename: Ken
authors.initials: K
authors.lastname: Resnicow
authors.forename: Frances E
authors.initials: FE
authors.lastname: Thompson
authors.forename: Amy L
authors.initials: AL
authors.lastname: Yaroch
authors.forename: Margaret
authors.initials: M
authors.lastname: Ehlers
authors.forename: Doug
authors.initials: D
authors.lastname: Midthune
authors.forename: Geoffrey C
authors.initials: GC
authors.lastname: Williams
authors.forename: Geoffrey W
authors.initials: GW
authors.lastname: Greene
authors.forename: Linda
authors.initials: L
authors.lastname: Nebeling
mesh_terms: D000293:Adolescent; D000328:Adult; D015982:Bias; D004032:Diet; D004041:Dietary Fats; D002149:Energy Intake; D005247:Feeding Behavior; D005260:Female; D005638:Fruit; D006801:Humans; D008297:Male; D011939:Mental Recall; D008875:Middle Aged; D012307:Risk Factors; D012928:Social Desirability; D014675:Vegetables
chemical_list: D004041:Dietary Fats