Reading the GAI–FSIQ difference on Wechsler reports: a practical note and a browser calculator

Wechsler protocols often print two global scores on a mean of 100 and a standard deviation of 15: Full Scale IQ (FSIQ) and the General Ability Index (GAI). FSIQ includes working memory and processing speed. GAI is restricted to reasoning subtests. Their difference, GAI minus FSIQ, is subtraction. Readers use it when one global number describes a scattered profile poorly. The lower indexes remain part of the record. This note describes that comparison on the WISC-V, WAIS-IV and WAIS-5, and the arithmetic a public browser page applies to scores pasted from a report. It is not a diagnosis. The examiner's report is the document a school or clinic can use.