Validation of a quantitative diet history method in Hawaii

The validity of a quantitative diet history method was evaluated among 262 men and women from the five major ethnic groups of Hawaii (Japanese, Caucasian, Chinese, Filipino, and Hawaiian) in 1984-1987. The reference data included four 1-week food records obtained at approximately 3-month intervals. The diet history was administered 6 months after the fourth week of food records and included 47 foods that were major sources of protein, fat, cholesterol, vitamins A and C, and beta-carotene. Photographs showing three portion sizes were utilized for quantifying intakes in the food records and the diet history. Generally, among all ethnic-sex groups, intakes from the diet history were greater than those from the record sets, particularly for the vitamins. Agreement was measured by the intraclass correlation coefficient (rl) and the weighted kappa statistic (kappa w), and consistency was measured by Spearman's rank correlation (rho). For the total group, the rl's ranged from 0.48 for vitamin A to 0.61 for cholesterol. The kappa w's were generally lower than the rl's, whereas the rho's were higher, ranging from 0.52 for vitamin C to 0.64 for cholesterol. Agreement among the ethnic-sex groups varied, with the Chinese females and the Japanese males having the higher rl's, and the Hawaiian males and females having the lowest values. The results provide evidence that the quantitative diet history gives reasonably accurate estimates of the usual dietary intakes among the major ethnic groups of Hawaii.