The results of studies examining the effectiveness of sensory integration therapy were reviewed, using recently developed quantitative methods that treat the literature review process as a unique type of research. Forty-nine studies were located initially. Eight of these studies met the following criteria: (a) they investigated the effect of sensory integration therapy; (b) they included dependent measures of academic achievement, motor or reflex performance, and / or language function; (c) they included a comparison between at least two groups; and (d) they reported quantitative results of the effect of sensory integration therapy. The 8 studies contained a total of 47 statistical hypothesis tests that evaluated the effectiveness of sensory integration therapy. An analysis of these tests, using quantitative reviewing methods, revealed that subjects participating in sensory integration therapy performed significantly better than members in the control groups who did not receive sensory integration therapy.
The application of sensory integration therapy to various client populations is discussed in relation to the existing empirical support revealed in the studies reviewed. The advantages of quantitative reviewing procedures are discussed, and use of the procedures with the developing occupational therapy research literature is recommended.