An index-based short-form of the WISC-IV with accompanying analysis of the reliability and abnormality of differences.

OBJECTIVES To develop an Index-based, seven subtest, short-form of the Wechsler intelligence scale for children fourth edition (WISC-IV) that offers the same comprehensive range of analytic methods available for the full-length version. DESIGN AND METHODS Psychometric. RESULTS The short-form Indexes had high reliability and criterion validity. Scores are expressed as Index scores and as percentiles. Methods are provided that allow setting of confidence limits on scores, and analysis of the reliability and abnormality of Index score differences. The use of the short-form is illustrated with a case example. A computer programme (that automates scoring and implements all the analytical methods) accompanies this paper and can be downloaded from the following web address: http://www.abdn.ac.uk/~psy086/dept/sf_wisc4.htm. CONCLUSIONS The short-form will be useful when pressure of time or client fatigue precludes use of a full-length WISC-IV. The accompanying computer programme scores and analyses an individual's performance on the short-form instantaneously and minimizes the chance of clerical error.