Use of self-report to monitor overweight and obesity in populations: some issues for consideration.
OBJECTIVE
To examine the validity of self-reported height and weight data reported over the telephone in the 1997 NSW Health Survey, and to determine its accuracy to monitor overweight and obesity in population surveys.


METHODS
Self-reported and measured heights and weights were collected from 227 people living in Western Sydney, who had participated in the NSW Health Survey 1997.


RESULTS
Self-reported (SR) weights and heights led to misclassification of relative weight status. BMI, based on measured weights and heights, classified 62% of males and 47% of females as overweight or obese, compared with 39% and 32%, respectively, from self-report.


CONCLUSIONS
Caution should be used when interpreting SR height and weight data from surveys, because BMI derived from these is likely to underestimate the true prevalence of overweight and obesity.


CONCLUSIONS
SR data have a place in nutrition monitoring because they are relatively inexpensive and easy to collect. However, classifying people into weight categories on the basis of accepted cut-points, using SR heights and weights, yields inaccurate prevalence estimates. Periodic sub-studies of the validity of SR heights and weights are needed to indicate the extent to which the validity of SR is changing.
Flood
V
V
Department of Public Health and Community Medicine, Westmead Hospital, University of Sydney, New South Wales. vicki@cmed.wsahs.nsw.gov.au
Webb
K
K
Lazarus
R
R
Pang
G
G
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015982:Bias; D001827:Body Height; D015992:Body Mass Index; D001835:Body Weight; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009517:New South Wales / Q000453:epidemiology; D009765:Obesity / Q000145:classification / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D011159:Population Surveillance / Q000379:methods*; D015995:Prevalence; D015203:Reproducibility of Results; D017678:Sex Distribution; D011795:Surveys and Questionnaires / Q000592:standards*; D013689:Telephone