Dr Janne Bigaard investigated the agreement between self-reported and technician-measured waist circumference at the level of the umbilicus.
The investigators also assessed circumference measured at the level of the umbilicus and halfway between the lower rib and the iliac crest/natural waist.
In addition, the team evaluated self-reported circumference at the level of the umbilicus and technician-measured circumference at the natural waist.
At follow-up in the Danish ‘Diet, Cancer and Health' study, the investigators recruited 176 men and 240 women for a validation study.
The investigative team used Bland-Altman plots to evaluate agreement among measurement sites.
Multiple regression was used to identify variables explaining the difference between measurements.
The team found that participants underestimated their waist circumference, as the mean differences were -2 cm in men and -3 cm in women.
| High body mass index was associated with larger degree of underreporting|
|Journal of Nutrition|
Limits of agreement were from -12 to +9 cm among men and -15 to +9 cm among women.
The team observed that high body mass index and large baseline waist circumference were associated with a larger degree of underreporting.
Waist circumference measured at the level of the umbilicus was larger than at the natural waist, and the mean differences were +0.7 cm in men and +5 cm in women.
The investigators noted that self-reported waist circumference at the level of the umbilicus correlated with the technician-measured circumference at the natural waist.
Dr Bigaard commented, “Circumference at the natural waist was overestimated for women, depending on baseline waist circumference.”
”Circumference at the natural waist was slightly underestimated for men, depending on baseline body mass index.”