Evaluation of the relative validity of a Web-based food frequency questionnaire used to assess Soy Isoflavones and nutrient intake in adolescents

Table 1 Demographic characteristics of the study population

Demographic Characteristic	Total Group (TeenFADS) (N = 601)	webFFQ Validation Sub-Study Group (n = 55)	p-value
Age in years, mean (SD)	15.0 (1.8)	15.3 (1.7)	0.17
Gender			0.57
Males, %	44	40
Females, %	56	60
Ethnicity			0.57
Caucasian, %	34	46
African/Afr-Am, %	9	6
Hispanic, %	14	16
Asians, %	11	7
Others, %	7	7
Mixed, %	18	18
Site			0.66
California, %	55	58
Michigan, %	45	42
Vegetarian, %	24	42	0.002
BMI z-scores, mean (SD)	0.35 (0.95)	0.49 (1.03)	0.24

ISSN: 2055-0928