当前位置： SCI文献检索 > PUBLIC HEALTH NUTRITION期刊下所有文献 > A combination of statistical methods for the analysis of the relative validation data of the quantitative food frequency questionnaire used in the THUSA study. Transition, Health and Urbanisation in South Africa.

A combination of statistical methods for the analysis of the relative validation data of the quantitative food frequency questionnaire used in the THUSA study. Transition, Health and Urbanisation in South Africa.

Abstract：

OBJECTIVE:To apply structural equation modelling (SEM) and estimation of variance components to the relative validation data obtained from the quantitative food frequency questionnaire (QFFQ) used in the Transition, Health and Urbanisation in South Africa (THUSA) study. DESIGN:A cross-sectional study. SETTING:A community-based field study in an African population conducted during 1996. SUBJECTS:Residents of the North West Province, South Africa, aged between 15 and 65 years. METHODS:Relative validity of the QFFQ was tested against 7-day weighed food records, 24-hour urinary nitrogen (UN) excretion and estimated basal metabolic rate (BMR). SEM and estimation of variance components were applied to the log-transformed energy, protein, fat, calcium, iron, vitamin A and vitamin C intakes. UN excretion was used as a biomarker in the application of the SEM to protein and estimated BMR to energy intakes. RESULTS:Constant bias (alphaQ) derived by the SEM varied from 0.85 (vitamin C) to 5.8 (energy). There was significant proportional bias for all nutrients except vitamin C. Validation coefficients (ro(Q,T) varied from 0.3 (fat, calcium, iron) to 0.7 (vitamin C). The inclusion of estimated BMR in the SEM for energy increased ro(Q, T) from 0.38 to 0.42. The estimation of variance components gave slightly lower correlations for the relationship between intakes from the QFFQ and the unknown true intake. CONCLUSIONS:Robust statistical methods were successfully applied in a relative validation study for a QFFQ in an African population. Estimated BMR as a biomarker for energy intake produced more meaningful results than UN excretion as a biomarker for protein intake.

journal_name

Public Health Nutr

journal_title

Public health nutrition

authors

MacIntyre UE,Venter CS,Vorster HH,Steyn HS

doi

10.1079/phn200039

subject

Has Abstract

pub_date

2001-02-01 00:00:00

pages

45-51

issue

eissn

1368-9800

issn

1475-2727

pii

S1368980001000076

journal_volume

pub_type

杂志文章

在线工具

A combination of statistical methods for the analysis of the relative validation data of the quantitative food frequency questionnaire used in the THUSA study. Transition, Health and Urbanisation in South Africa.