Internal consistency and construct validity of the WASI–II subtests and composite scores in a clinical sample

We determined WASI-II reliability for 100 outpatients with neurological, psychiatric, or developmental disorders. Means for age and education were 47.95 years (<i>SD</i> = 17.86) and 13.57 years (<i>SD</i> = 2.39). The design involved a total sample divided into neurological (<i>n =</i> 41) and psychiatric (<i>n</i> = 53) subgroups. Developmental disorders were included only in the total sample analyses (<i>n</i> = 6). Subtest split-half reliabilities ranged from .95 for Matrix Reasoning to .83 for Similarities. VCI, PRI, and FSIQ coefficients ranged from .91 to .97, .95 to .97, and .95 to .97. Omega (h) statistics, after controlling a general factor, were .408 and .365 for VCI and PRI. Support for WASI-II construct validity were also presented.