Table 1 Sensitivities, specificities, and detection times of various alert thresholds in Chabahar District, south-east Iran (21 Mar 2003-19 Mar 2008)
From: Defining and detecting malaria epidemics in south-east Iran
| Â | Earliest week epidemic detected (n = 13) | |||||
|---|---|---|---|---|---|---|
Thresholds | Sensitivity (percent) | Specificity (percent) | 1st | 2nd | 3rd | ≥ 4th |
Percentiles (1 week span) | Â | Â | Â | Â | Â | Â |
> 60% | 93.7 | 81.5 | 12 | 1 | 0 | 0 |
> 70% | 93.7 | 85.5 | 12 | 1 | 0 | 0 |
> 75% | 87.4 | 91.2 | 10 | 3 | 0 | 0 |
> 80% | 74.8 | 94.3 | 5 | 6 | 1 | 1 |
Percentiles (3 week span) | Â | Â | Â | Â | Â | Â |
> 60% | 96.5 | 81.7 | 12 | 1 | 0 | 0 |
> 70% | 95.1 | 87.5 | 12 | 1 | 0 | 0 |
> 75% | 94.4 | 90.5 | 12 | 1 | 0 | 0 |
> 80% | 90.9 | 93.1 | 11 | 2 | 0 | 0 |
> 85% | 78.3 | 95.6 | 6 | 6 | 1 | 0 |
Mean count + SD's (1 week span) | Â | Â | Â | Â | Â | Â |
> mean + 0.25SD | 97.2 | 89.4 | 12 | 1 | 0 | 0 |
> mean + 0.50SD | 93.7 | 93.4 | 10 | 3 | 0 | 0 |
> mean + 1.00SD | 81.8 | 97.2 | 6 | 6 | 1 | 0 |
> mean + 1.50SD | 69.9 | 98.2 | 4 | 6 | 2 | 1 |
Mean count + SD's (3 week span) | Â | Â | Â | Â | Â | Â |
> mean + 0.25SD* | 99.3 | 90.0 | 12 | 1 | 0 | 0 |
> mean + 0.50SD | 93.7 | 93.9 | 10 | 3 | 0 | 0 |
> mean + 1.00SD | 83.9 | 97.3 | 7 | 6 | 0 | 0 |
> mean + 1.50SD | 72.7 | 98.4 | 5 | 6 | 1 | 1 |
Mean log(count + 1) + SD's (1 week span) | Â | Â | Â | Â | Â | Â |
> mean + 0.25SD | 98.6 | 78.2 | 12 | 1 | 0 | 0 |
> mean + 0.50SD | 96.5 | 84.5 | 12 | 1 | 0 | 0 |
> mean + 1.00SD | 84.6 | 93.0 | 9 | 3 | 1 | 0 |
> mean + 1.50SD | 70.6 | 97.5 | 4 | 6 | 2 | 1 |
Mean log(count + 1) + SD's (1 week span) | Â | Â | Â | Â | Â | Â |
> mean + 0.25SD | 100.0 | 77.1 | 13 | 0 | 0 | 0 |
> mean + 0.50SD | 100.0 | 83.5 | 13 | 0 | 0 | 0 |
> mean + 1.00SD | 93.0 | 92.9 | 10 | 3 | 0 | 0 |
> mean + 1.50SD | 74.1 | 97.7 | 5 | 6 | 1 | 1 |