Table 2.
Diagnostic accuracy of the self-report and the informant-report AQ10 and AQ50
| Predictor | Cut-off | n | Sensitivity (95% CI) | Specificity (95% CI) | PPV (95% CI) | NPV (95% CI) | Accuracy, % | Youden J a |
|---|---|---|---|---|---|---|---|---|
| Self-report AQ10 | ⩾6 | 425 | 0.77 (0.72–0.82) | 0.28 (0.20–0.38) | 0.76 (0.70–0.80) | 0.30 (0.22–0.40) | 65 | 0.05 |
| Self-report AQ50 | ⩾26 | 453 | 0.88 (0.84–0.91) | 0.20 (0.13–0.28) | 0.76 (0.71–0.80) | 0.36 (0.25–0.49) | 70 | 0.07 |
| Self-report AQ50 | ⩾32 | 453 | 0.71 (0.65–0.75) | 0.35 (0.27–0.44) | 0.76 (0.71–0.80) | 0.29 (0.22–0.38) | 61 | 0.06 |
| Informant-report AQ10 | ⩾6 | 355 | 0.79 (0.73–0.84) | 0.31 (0.22–0.41) | 0.76 (0.72–0.81) | 0.35 (0.25–0.46) | 66 | 0.10 |
| Informant-report AQ50 | ⩾26 | 381 | 0.93 (0.89–0.95) | 0.14 (0.08–0.22) | 0.74 (0.69–0.79) | 0.41 (0.25–0.59) | 71 | 0.07 |
| Informant-report AQ50 | ⩾32 | 381 | 0.77 (0.72–0.82) | 0.38 (0.28–0.48) | 0.77 (0.72–0.82) | 0.38 (0.29–0.48) | 67 | 0.15 |
AQ10, 10-Item Autism-Spectrum Quotient; AQ50, 50-item AQ; CI, confidence interval; PPV, positive predictive value; NPV, negative predictive value.
a
Youden J is a summary measure of the informative power of a test, and is defined as (sensitivity + specificity – 1) (Youden, 1950). A Youden J value of 0 means the test is uninformative and J of 1 indicates that the test is perfectly informative. 95% CIs are shown in parentheses for sensitivity, specificity, PPV and NPV.