Table 2.
Predictive accuracy of back propagation ANN in relation to LS-BMD/F-BMD target
| ANN | Records in testing (n) | Low BMD (n) | Normal BMD (n) | Sensitivity (%) | Specificity (%) | Overall accuracy (%) | Area under the curve |
|---|---|---|---|---|---|---|---|
| Lumbar spine | |||||||
| FF_Bp 4 BA | 101 | 35 | 66 | 74.29 | 59.09 | 66.69 | 0.688 |
| FF_Bp 4 AB | 74 | 23 | 51 | 56.52 | 78.43 | 67.48 | 0.631 |
| Mean | 65.4 | 68.76 | 67.08 | 0.66 | |||
| Femur | |||||||
| FF_Bp 4 BA | 88 | 25 | 63 | 48 | 79.37 | 63.68 | 0.595 |
| FF_Bp 4 AB | 87 | 21 | 66 | 61.9 | 74.24 | 68.07 | 0.726 |
| Mean | 54.95 | 76.8 | 65.88 | 0.66 |
FF_Bp 4 AB, feed forward back propagation ANN with four hidden units: results obtained in sequence: training on subset A and testing on subset B; FF_Bp 4 BA, feed forward back propagation ANN with four hidden units: results obtained in sequence: training on subset b and testing on subset A.