Criterion validity of a computer-based tutorial for teaching waist circumference self-measurement

SummaryKnowing one's waist circumference (WC) is a primary step in assessing risk of disease and health disorders. One concern, however, is the accuracy with which WC measurements are taken. This study attempted to determine the effectiveness of a computer-based tutorial (CBT) in teaching previously untrained individuals to properly self-measure WC. Eighty-three subjects used the CBT to learn and perform WC self-measurement. Validity of the subjects’ measurements was determined by comparing their measurements to a traditionally trained and experienced tester's. Bland–Altman and Box–Whisker comparisons revealed an average 1.57 cm bias in the subjects’ WC measurements. Bland–Altman bias plots illustrated agreement between the subjects’ and experienced tester's measurements. Pearson correlation (r=0.97) showed no significant (p<0.0001) difference between the two groups. The results of this experiment suggest that the tested CBT is efficacious in teaching WC self-measurement. The tutorial could be used in the areas of health assessment, standardization, biomedical education and research.