Remediation of cognitive deficits: a critical appraisal of the Feuerstein model.

It has been reported that the Instrumental Enrichment (IE) programme can successfully modify the cognitive structures of retarded disadvantaged adolescents. The research from both Israeli and American studies was reviewed to determine how strongly those claims for success were supported. Though the research yielded some statistically significant results in favour of the Instrumental Enrichment group, the importance of those findings are challenged on the grounds of research design, the relatively unimportant magnitude of mean differences that are reported as significant, and the failure of score changes on measures of cognitive ability to be reflected in school performance. It is concluded that claims that research leads 'substantial support' to the effectiveness of the IE programme must be rejected.