Types of Errors in Synthesizing Research in Education

Nine types of errors occurring in three stages of the process of synthesizing research are described and illustrated with examples from a recent synthesis ( Kagan, 1992 ) of research on teacher professional growth. Errors can occur in the initial identification and collection of reports of research, in the analysis of documents, and in the final stage of reaching generalizations about the whole body of research. Types of errors include the exclusion of relevant literature, wrongly reporting details such as sample size, erroneously attributing findings to studies, and stating unwarranted conclusions about the research reviewed. Implications for reviewers and users of reviews are considered.