In reality, conducting a group test requires as much finesse as administering an individual tests, a point recognized years ago by Traxler (1951). There are numerous ways in which careless administration and scoring can impair group test results, causing bias for the entire group or affecting only certain individuals. We outline only the more important inadequacies and errors in the following paragraphs, referring the reader to Traxler(1951) and Clemans(1971) Or a more complete discussionnd collecting the materials