Table 3.
Measurement performance of drug use assessments for adults with schizophrenia: Self-report as criterion
| Measure |
Self-report
|
||||||
|---|---|---|---|---|---|---|---|
| Detection ratio | AUC (SE) | AUC 95%CI | Sensitivity | Specificity | Percent Classified Correctly | Cohen’s Kappa | |
| Urine | |||||||
| Marijuana | 0.52† | .70 (.02) | .66–.74† | 41.9% | 97.8% | 88.3% | 0.49 |
| Cocaine | 0.74† | .72 (.03) | .67–.78† | 47.2% | 97.6% | 93.0% | 0.51 |
| Opiate | 1.36 | .67 (.07) | .47–.76† | 25.0% | 98.5% | 97.7% | 0.20 |
| Stimulant | 0.30† | .62 (.06) | .50–.75 | 25.0% | 99.9% | 98.4% | 0.37 |
| All tested drugs | 0.70† | .72 (.02) | .68–.76† | 49.5% | 94.1% | 84.3% | 0.49 |
| Hair | |||||||
| Marijuana | 0.87 | .70 (.03) | .65–.75† | 48.8% | 91.9% | 84.6% | 0.43 |
| Cocaine | 2.08† | .86 (.02) | .81–.90† | 83.7% | 87.7% | 87.3% | 0.44 |
| Opiate | 1.86 | .64 (.08) | .48–.79 | 29.4% | 97.8% | 97.1% | 0.20 |
| Stimulant | 1.30 | .84 (.06) | .72–.95† | 68.0% | 98.9% | 98.3% | 0.62 |
| All tested drugs | 1.30† | .76 (.02) | .72–.79† | 68.8% | 82.5% | 79.5% | 0.46 |
| Any laboratory test | |||||||
| Marijuana | 0.87 | .75 (.02) | .71–.79† | 56.3% | 93.7% | 87.3% | 0.53 |
| Cocaine | 1.84† | .81 (.02) | .76–.85† | 71.5% | 89.5% | 87.9% | 0.44 |
| Opiate | 2.36† | .74 (.07) | .60–.88† | 50.0% | 97.3% | 96.9% | 0.28 |
| Stimulant | 1.05 | .82 (.06) | .71–.93† | 64.3% | 99.2% | 98.5% | 0.61 |
| All tested drugs | 1.25† | .77 (.02) | .74–.80† | 69.9% | 84.3% | 81.1% | 0.50 |
†
=Bonferonni adjusted p-value (p<0.01)