Background
Methods
Setting: Million Women Study
Study sample and data collection
Year (mean) | Anthropometric variables collected | |
---|---|---|
1st (recruitment) questionnairea | 1999 | Self-reported weight and height |
2nd questionnairea | 2002 | Self-reported weight, waist and hips |
3rd questionnairea | 2006 | Self-reported weight, waist and hips |
Additional questionnaire | 2008 | Self-reported weight, height, waistb and hipsb |
Examination | 2008 | Measured weight, height, waistb and hipsb |
Data analysis
Results
Mean year of report | Mean year of measurement | ||||
---|---|---|---|---|---|
1999 | 2002a | 2006 | 2008 | 2008 | |
Age at time of report or measurement, mean (SD) | 56.1 (4.6) | 60.1 (4.7) | 64.1 (4.6) | 65.7 (4.7) | 66.0 (4.7) |
Anthropometry: | |||||
Weight, kg, mean (SD) | 67.1 (11.2) | 67.6 (11.5) | 68.4 (11.9) | 68.4 (11.9) | 69.8 (12.6) |
Height, cm, mean (SD)b | 162.7 (6.5) | NA | NA | 162.2 (6.3) | 161.5 (6.3) |
BMI, kg/m2, mean (SD)b | 25.4 (4.1) | 25.5 (4.2) | 25.8 (4.4) | 26.0 (4.4) | 26.8 (4.7) |
Waist, cm, mean (SD) | NA | 76.8 (9.3) | 79.3 (10.0) | 82.2 (10.3) | 88.8 (12.6) |
Hips, cm, mean (SD) | NA | 100.3 (7.5) | 100.6 (7.8) | 101.6 (8.2) | 104.7 (10.3) |
Characteristic Mean year of reporta | N | Mean difference (se)b Reported – measured | Pearson correlation | Regression dilution ratio (95 % CI)c |
---|---|---|---|---|
Weight (kg) | ||||
1999 | 3893 | −2.6 (0.10) | 0.88 | 1.00 (0.98–1.01) |
2002 | 3530 | −1.8 (0.09) | 0.91 | 0.99 (0.98–1.00) |
2006 | 3870 | −1.2 (0.07) | 0.94 | 0.99 (0.98–1.00) |
2008 | 3921 | −1.1 (0.05) | 0.97 | 1.02 (1.01–1.02) |
P for trend | <0.001 | <0.001 | 0.07 | |
Height (cm)d | ||||
1999 | 3951 | 1.2 (0.05) | 0.88 | 0.85 (0.84–0.87) |
2008 | 3943 | 0.8 (0.04) | 0.91 | 0.89 (0.88–0.90) |
P for trend | <0.001 | 0.003 | 0.02 | |
BMI (kg/m
2
)
d
| ||||
1999 | 3863 | −1.4 (0.04) | 0.85 | 0.98 (0.96–1.00) |
2002 | 3496 | −1.1 (0.04) | 0.88 | 0.96 (0.95–0.98) |
2006 | 3834 | −0.9 (0.03) | 0.91 | 0.97 (0.96–0.99) |
2008 | 3887 | −0.7 (0.02) | 0.95 | 1.01 (1.00–1.02) |
P for trend | <0.001 | <0.001 | 0.30 | |
Waist (cm)e | ||||
2002 | 1771 | −10.3 (0.21) | 0.66 | 0.84 (0.80–0.88) |
2006 | 1717 | −7.2 (0.21) | 0.68 | 0.78 (0.74–0.82) |
2008 | 2153 | −5.2 (0.18) | 0.71 | 0.80 (0.77–0.83) |
P for trend | <0.001 | <0.001 | 0.08 | |
Hips (cm)e | ||||
2002 | 1774 | −2.8 (0.15) | 0.75 | 0.95 (0.91–0.99) |
2006 | 1724 | −2.3 (0.15) | 0.76 | 0.90 (0.87–0.94) |
2008 | 2165 | −2.0 (0.12) | 0.82 | 0.95 (0.92–0.97) |
P for trend | <0.001 | <0.001 | 0.70 |