Table.
Participant characteristics at time of measured weight and validity of self-reported weights following bariatric surgery.
| Women | Men | P-valuea | |
|---|---|---|---|
| Participant Characteristics | |||
| Number of participants | 808 | 180 | |
| Age (years), mean (SD) [range] | 49 (11) [21 to 79] | 55 (11) [28 to 80] | <0.001 |
| BMI (kg/m2), mean (SD) [range] | 33.0 (7.0) [ 19.0 to 63.2] | 34.6 (5.8) [23.2 to 52.6] | 0.002 |
| Weight change (%), mean (SD) [range] | −28.3 (12.3) [−58.3 to 13.0] | −24.3 (11.2) [−49.5 to 11.3] | <0.001 |
| Bariatric Procedure, n (%) | |||
| Roux-en-Y gastric bypass | 603 (74.6) | 131 (72.8) | 0.61 |
| Laparoscopic adjustable gastric band | 205 (25.4) | 49 (27.2) | |
| All Self-Reported Weights | |||
| Number of participants | 808 | 180 | |
| Measured weight (kg), mean (SD) [range] | 89.6 (20.2) [45.0 to 194.1] | 111.6 (20.7) [74.1 to 180.0] | |
| Self-reported weight (kg), mean (SD) [range] | 88.9 (20.3) [44.5 to 195.9] | 110.6 (21.0) [72.7 to 184.1] | |
| Self-reported weight minus measured weight (kg) | |||
| Mean weight difference (SD) [range] | −0.7 (1.9) [−10.9 to 6.8] | −1.0 (2.7) [−10.9 to 11.8] | 0.09 |
| 95% Confidence interval | (−0.81, −0.56) | (−1.34, −0.59) | |
| P-valueb | <0.001 | <0.001 | |
| Percent differencec (%) | |||
| Mean percent difference (SD) [range] | −0.8 (2.1) [−11.8 to 10.4] | −0.9 (2.3) [−8.9 to 8.7] | 0.46 |
| 95% Confidence interval | (−0.93, −0.65) | (−1.20, −0.59) | |
| P-valueb | <0.001 | <0.001 | |
| Self-Reported Medical Weights | |||
| Number of participants | 329 | 79 | |
| Measured weightd (kg), mean (SD) [range] | 90.1 (21.9) [45.0 to 194.1] | 115.1 (22.6) [77.3 to 180.0] | |
| Self-reported medical weight (kg), mean (SD) [range] | 90.0 (22.0) [44.5 to 195.9] | 115.1 (23.1) [76.4 to 184.1] | |
| Self-reported medical weight minus measured weight (kg) | |||
| Mean weight difference (SD) [range] | −0.1 (1.8) [−6.8 to 6.8] | 0.1 (2.8) [−10.5 to 11.8] | 0.67 |
| 95% Confidence interval | (−0.26, 0.13) | (−0.56, 0.72) | |
| P-valueb | 0.53 | 0.80 | |
| Percent differencec (%) | |||
| Mean percent difference (SD) [range] | −0.1 (2.0) [−6.4 to 10.4] | 0.0 (2.2) [−6.6 to 8.7] | 0.70 |
| 95% Confidence interval | (−0.30, 0.13) | (−0.49, 0.52) | |
| P-valueb | 0.42 | 0.95 | |
| Self-Reported Personal Weights | |||
| Number of participants | 673 | 151 | |
| Measured weightd (kg), mean (SD) [range] | 89.3 (19.5) [49.1 to 182.7] | 110.6 (19.7) [74.1 to 170.0] | |
| Self-reported personal weight (kg), mean (SD) [range] | 88.4 (19.5) [48.2 to 181.8] | 109.1 (19.8) [72.7 to 172.7] | |
| Self-reported personal weight minus measured weight (kg) | |||
| Mean weight difference (SD) [range] | −0.9 (1.8) [−10.9 to 6.8] | −1.5 (2.4) [−10.9 to 3.6] | 0.01 |
| 95% Confidence interval | (−1.07, −0.79) | (−1.87, −1.08) | |
| P-valueb | <0.001 | <0.001 | |
| Percent differencec | |||
| Mean percent difference (SD) [range] | −1.1 (2.1) [−11.8 to 7.3] | −1.4 (2.2) [−8.9 to 3.3] | 0.11 |
| 95% Confidence interval | (−1.22, −0.90) | (−1.72, −1.03) | |
| P-valueb | <0.001 | <0.001 |
Discrepancies between the mean weights and the mean differences are due to rounding. SD is the standard deviation.
a
P-values comparing women and men.
b
P-values comparing the mean or percent difference to 0.
c
Percent difference=[(self-reported weight – measured weight) / measured weight] × 100.
d
Measured weights of those participants with the corresponding self-reported weight.