Table 2.
Classification Agreement for Identification Decisions Based on Recursive Test–Retest Procedure With Latent SLD Status and Comparison With Single Measure Indicators (N = 1,000,000).
| Parameters |
Latent classifications |
Observed classifications |
Agreement |
Increase in correct classificationsb |
Increase in true positivec |
|||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Reliability |
Meaningful difference |
Referred samplea |
Latent LD |
LD |
True positive |
False positive |
False negative |
True negative |
Sen. |
Spec. |
PPV |
NPV |
||
| r | SD | n | n | % | n | n | n | n | % | % | % | % | n(%) | % |
| .95 | 0.5 | 221,721 | 39,594 | 17.86 | 17,986 | 3,165% | 21,608 | 178,962 | 45.4 | 98.3 | 85.0 | 89.2 | 272 (0.1) | −2,871.0 |
| .95 | 1 | 221,721 | 20,874 | 9.41 | 12,497 | 8,654% | 8,377 | 192,193 | 59.9 | 95.7 | 59.1 | 95.8 | 9,576 (4.9) | −33.0 |
| .95 | 1.25 | 221,721 | 11,329 | 5.11 | 7,197 | 13,954 | 4,132 | 196,438 | 63.5 | 93.4 | 34.0 | 97.9 | 12,894 (6.8) | −11.6 |
| .9 | 0.5 | 222,363 | 39,240 | 17.65 | 9,450 | 3,126% | 29,790 | 179,997 | 24.1 | 98.3 | 75.1 | 85.8 | −641 (−0.3) | 1,256.8 |
| .9 | 1 | 222,363 | 20,634 | 9.28 | 9,497 | 3,079% | 11,137 | 198,650 | 46.0 | 98.5 | 75.5 | 94.7 | 6,427 (3.2) | −70.4 |
| .9 | 1.25 | 222,363 | 11,198 | 5.04 | 6,588 | 5,988% | 4,610 | 205,177 | 58.8 | 97.2 | 52.4 | 97.8 | 11,387 (5.7) | −17.9 |
| .85 | 0.5 | 223,154 | 38,783 | 17.38 | 5,072 | 2,172% | 33,711 | 182,199 | 13.1 | 98.8 | 70.0 | 84.4 | −626 (−0.3) | 1,166.1 |
| .85 | 1 | 223,154 | 20,324 | 9.11 | 5,757 | 1,487% | 14,567 | 201,343 | 28.3 | 99.3 | 79.5 | 93.3 | 3,734 (1.8) | −137.1 |
| .85 | 1.25 | 223,154 | 10,994 | 4.93 | 4,443 | 2,801% | 6,551 | 209,359 | 40.4 | 98.7 | 61.3 | 97.0 | 8,584 (4.2) | −31.4 |
| .8 | 0.5 | 223,590 | 38,270 | 17.12 | 3,152 | 1,625% | 35,118 | 183,695 | 8.2 | 99.1 | 66.0 | 84.0 | −236 (−.1) | 2,796.6 |
| .8 | 1 | 223,590 | 20,022 | 8.95 | 3,759 | 1,018% | 16,263 | 202,550 | 18.8 | 99.5 | 78.7 | 92.6 | 2,998 (1.5) | −166.2 |
| .8 | 1.25 | 223,590 | 10,821 | 4.84 | 3,046 | 1,731% | 7,775 | 211,038 | 28.2 | 99.2 | 63.8 | 96.5 | 7,244 (3.5) | −39.5 |
| .75 | 0.5 | 224,247 | 37,769 | 16.84 | 1,925 | 1,103% | 35,844 | 185,375 | 5.1 | 99.4 | 63.6 | 83.8 | 139 (0.1) | −4,143.2 |
| .75 | 1 | 224,247 | 19,649 | 8.76 | 2,321 | 707% | 17,328 | 203,891 | 11.8 | 99.7 | 76.7 | 92.2 | 2,531 (1.2) | −180.3 |
| .75 | 1.25 | 224,247 | 10,618 | 4.73 | 1,921 | 1,107% | 8,697 | 212,522 | 18.1 | 99.5 | 63.4 | 96.1 | 6,075 (2.9) | −45.9 |
Note. LD = learning disability; Sen. = sensitivity; Spec. = specificity; PPV = positive predictive value; NPV = negative predictive value.
a
Referred sample = all students with standard score < 90 on academic measure and IQ > 70.
b
Improvement over classification accuracy of one indicator (see Table 1).
c
True positive percentage represents proportion of change in correct classifications accounted for by increase in true positive classifications.