Development and evaluation of cultural food frequency questionnaires for South Asians, Chinese, and Europeans in North America

We developed three ethnic food frequency questionnaires (FFQs) to characterize the diets of South Asian, Chinese, and European immigrants. FFQs were developed from foods reported in the diet records and recalls of 29 South Asians, 25 Chinese, and 20 Europeans participating in a pilot study from 1995-1996 in Hamilton, Ontario, Canada. The FFQ and a seven-day diet record were then administered to 342 South Asians, 317 Chinese, and 346 Europeans participating in the Study of Health Assessment and Risk in Ethnic groups (SHARE) in three Canadian centers from 1996-1998. For FFQ validation, a subset of these participants completed a second seven-day diet record and second FFQ 8 to 10 months later. The FFQ generally underestimated macronutrient and overestimated micronutrient intake compared with the records. Consumption of most macronutrients was lower among South Asians. Energy-adjusted deattenuated correlation coefficients between the records and second FFQ ranged from 0.32 to 0.73 (South Asians), 0.17 to 0.84 (Chinese), and 0.30 to 0.83 (Europeans). The FFQs generally performed well and will be used to investigate diet-disease relations in SHARE. Lower correlations for dietary fats among Chinese persons (0.17 to 0.31) may be improved with more direct questions on the FFQ regarding brand, type, and amount of oil consumed in stirfry servings.