REPORTING THE SIZE OF EFFECTS IN RESEARCH STUDIES TO FACILITATE ASSESSMENT OF PRACTICAL OR CLINICAL-SIGNIFICANCE

''Statistically significant'' results may lack practical or clinical significance, and the description of results in reports of research studies is frequently incomplete or misleading in presentation of data necessary to assess such significance (effect sizes). Various common presentations are discussed, and one method of presentation of results is proposed that not only encompasses all the others, but enhances the scope of useful information conveyed in a research report. The results of the Infant Health and Development Program (IHDP) are used to illustrate the method.