Background
Methods
Data
Procedure
a) Development and estimation of weight-only correction equation
b) Evaluation of correction equations: comparison of BMI distributions; estimation of sensitivity and specificity for weight categories; and prediction of health outcomes
Results
Distribution of BMI
Sensitivity and specificity of corrected and self-reported BMI
MALES – Selected BMI indicators versus measured BMI | ||||||
---|---|---|---|---|---|---|
Normal weight | Overweight | Obese | ||||
Sens
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Spec
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Sens
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Spec
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Sens
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Spec
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Self-reported | 91.03 | 83.31 | 73.03 | 79.84 | 60.59 | 98.52 |
(86.21 to 95.85) | (80.16 to 86.45) | (68.29 to 77.78) | (75.40 to 84.28) | (52.91 to 68.27) | (97.56 to 99.48) | |
BMI Correction | 77.11 | 92.85 | 82.18 | 80.02 | 79.72 | 94.87 |
(70.59 to 83.63) | (90.70 to 95.00) | (77.97 to 86.39) | (75.60 to 84.44) | (73.63 to 85.60) | (92.97 to 96.77) | |
Weight-only Correction | 81.07 | 89.86 | 80.15 | 80.94 | 75.6 | 96.82 |
(74.62 to 87.52) | (87.20 to 92.51) | (75.82 to 84.48) | (76.40 to 85.49) | (68.79 to 82.42) | (95.48 to 98.16) | |
Weight-only Corr. (Simple) | 81.22 | 89.86 | 80.15 | 80.94 | 75.6 | 96.82 |
(74.77 to 87.67) | (87.20 to 92.51) | (75.82 to 84.48) | (76.40 to 85.49) | (68.79 to 82.42) | (95.48 to 98.16) | |
FEMALES – Selected BMI indicators versus measured BMI
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Normal weight
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Overweight
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Obese
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Sens
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Spec
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Sens
|
Spec
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Sens
|
Spec
| |
Self-reported | 91.57 | 78.66 | 63.01 | 88.97 | 66.44 | 99.07 |
(88.44 to 94.70) | (74.95 to 82.34) | (56.87 to 69.14) | (86.03 to 91.90) | (59.11 to 73.77) | (98.51 to 99.63) | |
BMI Correction | 86.08 | 87.71 | 76.88 | 87.92 | 81.4 | 96.55 |
(81.83 to 90.34) | (84.88 to 90.55) | (71.62 to 82.15) | (84.88 to 90.97) | (75.65 to 87.15) | (95.12 to 97.98) | |
Weight-only Correction | 86.17 | 88.96 | 75.31 | 89 | 81.62 | 96.42 |
(82.13 to 90.21) | (86.28 to 91.63) | (69.96 to 80.66) | (86.13 to 91.87) | (75.87 to 87.36) | (94.98 to 97.86) | |
Weight-only Corr. (Simple) | 86.64 | 88.21 | 74.13 | 89.33 | 81.7 | 96.42 |
(82.66 to 90.62) | (85.46 to 90.96) | (68.69 to 79.56) | (86.50 to 92.16) | (75.96 to 87.44) | (94.98 to 97.86) |
Predictive utility of corrected BMI in health condition models
Measured BMI | Self-reported BMI | BMI correction | Weight-only correction | Weight-only correction (simple) | ||||||
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Health condition | OR | 95% CI | OR | 95% CI | OR | 95% CI | OR | 95% CI | OR | 95% CI |
Arthritis
| ||||||||||
Normal weight | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | |||||
Overweight | 0.92 | 0.35 to 2.46 | 1.81 | 0.90 to 3.64 | 1.78 | 0.82 to 3.86 | 1.98 | 0.93 to 4.23 | 1.98 | 0.93 to 4.23 |
Obese (Class I) | 0.98 | 0.34 to 2.81 | 2.00 | 0.86 to 4.67 | 1.61 | 0.69 to 3.80 | 2.07 | 0.90 to 4.76 | 2.03 | 0.87 to 4.74 |
Obese (Class II+) | 1.52 | 0.43 to 5.33 | 3.79* | 1.40 to 10.28 | 2.54* | 1.00 to 6.41 | 2.83* | 1.09 to 7.33 | 2.88* | 1.15 to 7.23 |
Heart disease
| ||||||||||
Normal weight | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | |||||
Overweight | 0.84 | 0.30 to 2.37 | 1.23 | 0.46 to 3.35 | 1.45 | 0.47 to 4.51 | 0.97 | 0.34 to 2.72 | 0.97 | 0.34 to 2.72 |
Obese (Class I) | 1.36 | 0.41 to 4.53 | 1.42 | 0.48 to 4.22 | 1.21 | 0.35 to 4.17 | 0.92 | 0.28 to 3.02 | 0.96 | 0.29 to 3.14 |
Obese (Class II+) | 0.79 | 0.19 to 3.27 | 1.82 | 0.40 to 8.20 | 2.21 | 0.62 to 7.95 | 2.02 | 0.61 to 6.64 | 1.82 | 0.56 to 5.94 |
Diabetes
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Normal weight | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | |||||
Overweight | 0.99 | 0.33 to 2.95 | 0.75 | 0.29 to 1.93 | 1.30 | 0.45 to 3.74 | 1.32 | 0.47 to 3.70 | 1.32 | 0.47 to 3.70 |
Obese (Class I) | 2.90* | 1.02 to 8.22 | 2.05 | 0.71 to 5.92 | 2.28 | 0.76 to 6.82 | 2.68 | 0.93 to 7.71 | 2.78 | 0.97 to 8.05 |
Obese (Class II+) | 4.81* | 1.48 to 15.64 | 5.89* | 2.04 to 17.01 | 5.40* | 1.76 to 16.52 | 6.95* | 2.34 to 20.67 | 6.07* | 2.06 to 17.88 |
High blood pressure
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Normal Weight | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | |||||
Overweight | 1.01 | 0.50 to 2.04 | 1.56 | 0.85 to 2.87 | 1.28 | 0.63 to 2.60 | 1.02 | 0.53 to 1.96 | 1.02 | 0.53 to 1.96 |
Obese (Class I) | 2.98* | 1.38 to 6.44 | 3.46* | 1.64 to 7.32 | 3.30* | 1.51 to 7.22 | 3.40* | 1.66 to 6.97 | 3.47* | 1.68 to 7.15 |
Obese (Class II+) | 4.56* | 1.81 to 11.50 | 5.33* | 2.04 to 13.95 | 3.00* | 1.19 to 7.54 | 2.98* | 1.21 to 7.39 | 2.85* | 1.18 to 6.88 |
Self-reported health (fair or poor)
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Normal weight | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | |||||
Overweight | 0.75 | 0.35 to 1.63 | 0.84 | 0.42 to 1.66 | 0.61 | 0.28 to 1.29 | 0.58 | 0.28 to 1.23 | 0.58 | 0.28 to 1.23 |
Obese (Class I) | 1.26 | 0.59 to 2.71 | 1.65 | 0.79 to 3.47 | 1.32 | 0.61 to 2.88 | 1.54 | 0.73 to 3.24 | 1.61 | 0.76 to 3.39 |
Obese (Class II+) | 1.33 | 0.48 to 3.71 | 1.50 | 0.57 to 3.96 | 1.55 | 0.62 to 3.88 | 1.93 | 0.79 to 4.74 | 1.70 | 0.70 to 4.16 |
Activity limitation (often or sometimes)
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Normal weight | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | |||||
Overweight | 1.13 | 0.66 to 1.93 | 1.08 | 0.65 to 1.78 | 0.95 | 0.55 to 1.64 | 0.92 | 0.54 to 1.56 | 0.92 | 0.54 to 1.56 |
Obese (Class I) | 1.53 | 0.79 to 2.96 | 1.70 | 0.90 to 3.24 | 1.18 | 0.62 to 2.26 | 1.35 | 0.72 to 2.56 | 1.43 | 0.75 to 2.70 |
Obese (Class II+) | 2.55* | 1.15 to 5.65 | 3.53* | 1.51 to 8.25 | 1.88 | 0.83 to 4.25 | 2.38* | 1.03 to 5.54 | 2.01 | 0.89 to 4.53 |
Measured BMI | Self-reported BMI | BMI correction | Weight-only correction | Weight-only correction (simple) | ||||||
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Health condition | OR | 95% CI | OR | 95% CI | OR | 95% CI | OR | 95% CI | OR | 95% CI |
Arthritis
| ||||||||||
Normal weight | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | |||||
Overweight | 1.08 | 0.61 to 1.90 | 1.04 | 0.61 to 1.77 | 1.21 | 0.69 to 2.11 | 1.22 | 0.70 to 2.13 | 1.02 | 0.58 to 1.77 |
Obese (Class I) | 1.24 | 0.66 to 2.34 | 2.72* | 1.56 to 4.74 | 1.67 | 0.94 to 2.97 | 1.70* | 0.96 to 3.00 | 1.54 | 0.87 to 2.74 |
Obese (Class II+) | 4.97* | 2.45 to 10.08 | 4.29* | 1.85 to 9.97 | 5.04* | 2.45 to 10.37 | 4.92* | 2.41 to 10.04 | 4.36* | 2.16 to 8.79 |
Heart disease
| ||||||||||
Normal weight | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | |||||
Overweight | 0.47 | 0.10 to 2.23 | 2.50 | 0.69 to 8.96 | 1.78 | 0.48 to 6.65 | 1.90 | 0.51 to 7.09 | 1.97 | 0.53 to 7.33 |
Obese (Class I) | 1.45 | 0.34 to 6.16 | 2.64 | 0.96 to 7.22 | 1.63 | 0.55 to 4.84 | 1.64 | 0.54 to 4.95 | 1.69 | 0.56 to 5.10 |
Obese (Class II+) | 2.04 | 0.39 to 10.64 | 4.54 | 0.83 to 24.67 | 3.29 | 0.82 to 13.14 | 3.44 | 0.88 to 13.55 | 3.43 | 0.87 to 13.47 |
Diabetes
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Normal weight | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | |||||
Overweight | 0.71 | 0.21 to 2.46 | 1.43 | 0.41 to 4.94 | 6.28* | 1.67 to 23.56 | 4.30* | 1.25 to 14.77 | 4.45* | 1.29 to 15.32 |
Obese (Class I) | 0.90 | 0.24 to 3.33 | 1.85 | 0.65 to 5.26 | 3.51* | 1.01 to 12.13 | 2.53 | 0.83 to 7.71 | 2.42 | 0.87 to 7.51 |
Obese (Class II+) | 3.13 | 0.78 to 12.44 | 5.26* | 1.23 to 22.36 | 14.56* | 3.79 to 55.93 | 10.29* | 3.01 to 35.25 | 10.55* | 3.12 to 35.60 |
High blood pressure
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Normal weight | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | |||||
Overweight | 1.45 | 0.70 to 3.01 | 2.12* | 1.12 to 4.00 | 1.84 | 0.92 to 3.67 | 1.94 | 0.97 to 3.85 | 2.00* | 1.01 to 3.99 |
Obese (Class I) | 2.26* | 1.09 to 4.69 | 3.70* | 1.99 to 6.89 | 3.19* | 1.65 to 6.13 | 3.27* | 1.70 to 6.28 | 3.38* | 1.75 to 6.50 |
Obese (Class II+) | 5.28* | 2.20 to 12.68 | 7.15* | 2.57 to 19.90 | 5.50* | 2.27 to 13.27 | 5.54* | 2.32 to 13.26 | 5.55* | 2.35 to 13.09 |
Self-reported health (fair or poor)
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Normal weight | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | |||||
Overweight | 0.70 | 0.34 to 1.44 | 1.05 | 0.51 to 2.17 | 0.95 | 0.46 to 1.95 | 0.98 | 0.47 to 2.01 | 1.02 | 0.49 to 2.10 |
Obese (Class I) | 1.19 | 0.54 to 2.62 | 2.25* | 1.12 to 4.53 | 1.31 | 0.63 to 2.69 | 1.34 | 0.65 to 2.75 | 1.18 | 0.59 to 2.37 |
Obese (Class II+) | 2.29 | 0.84 to 6.22 | 2.55 | 0.69 to 9.30 | 2.37 | 0.86 to 6.50 | 2.37 | 0.87 to 6.46 | 2.70* | 1.03 to 7.12 |
Activity limitation (often or sometimes)
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Normal weight | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | |||||
Overweight | 1.23 | 0.75 to 2.02 | 1.31 | 0.79 to 2.19 | 0.96 | 0.58 to 1.57 | 0.97 | 0.59 to 1.58 | 0.90 | 0.55 to 1.47 |
Obese (Class I) | 1.81 | 0.96 to 3.43 | 2.03* | 1.15 to 3.57 | 1.74 | 0.93 to 3.23 | 1.74 | 0.94 to 3.24 | 1.57 | 0.84 to 2.94 |
Obese (Class II+) | 3.80* | 1.90 to 7.62 | 3.70* | 1.50 to 9.13 | 3.20* | 1.49 to 6.91 | 3.19* | 1.50 to 6.82 | 3.30* | 1.56 to 6.98 |