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. 2018 May 5;8(5):e019454. doi: 10.1136/bmjopen-2017-019454

Table 4.

C-statistic, sensitivity, specificity and PPV

C-statistic (overall model)=0.78
Cut-off points for comparison
‘At higher risk’* score ‘At higher risk’*+‘Higher than average’† score
Sensitivity‡ 0.43 0.70
Specificity§ 0.91 0.72
PPV¶ 0.06 0.03
True positives** 2737 4495

*‘At higher risk’ is defined as patients with a predicted risk of hospitalisation of>2.5%.

†‘At higher risk’+‘Higher than average’, is defined as patients with a predicted risk of hospitalisation of >1.2%.

‡Sensitivity is defined as the proportion of those hospitalised who were predicted to be hospitalised (true positive rate).

§Specificity is the proportion of those not hospitalised who were not predicted to be hospitalised (true negative rate).

¶PPV is the proportion of those predicted to be hospitalised who were actually hospitalised.

**Positive predictives are the number of residents who were predicted to be at risk of hospitalisation at the predicted risk threshold and were actually hospitalised.

PPV, positive predictive value.