As a continuing part of its validity studies, the Association of American Medical Colleges commissioned a study of the speediness of the Medical College Admission Test (MCAT). If speed is a hidden part of the test, it is a threat to its construct validity. As a general rule, the criterion used to indicate lack of speediness is that 80% of the examinees will finish 100% of the items on a test and that 100% of the examinees will finish 80% of the items. Previous studies have indicated that this rule is not violated by the MCAT. For this study, the frequencies of omitted items and items "not reached" were tabulated, with counts of omitted items including items not reached. Items in the not reached category are an indication of speediness since they represent omitted items only at the end of a test section. Data were examinee responses to three of four test sections (physical sciences, biological sciences, and verbal reasoning). Data came from forms of the MCAT administered to 16,520 testtakers in 1994, 3,638 testtakers in 1994, and 12,625 examinees in 1996. The various analyses , including split half reliabilities, reveal no evidence of speediness on the science sections of the MCAT. The verdict is not so clear for the verbal reasoning section of the test. Patterns of omitted and "not reached" items exceeded the proportions of the science tests, and patterns of guessing were also noticeable. The evidence for speediness is not glaring and does not violate normally acceptable standards. Nor is there evidence that any speediness affects any particular group differentially. (Contains 59 tables, 12 figures, and 2 references.) (SLD)