The purpose of this study was: (1) to examine the scores achieved by psychiatrically ill adults who successfully passed the Test of General Educational Development while patients at the Arizona State Hospital; (2) to examine the scores achieved by non-psychiatrically ill adults who successfully passed the Test of General Educational Development; and (3) to determine if there was a significant difference in the scores attained on the five sub-tests of the Test of General Educational Development between psychiatrically ill adult and the non-psychiatrically ill adult. The null hypothesis tested was: There is no significant difference between the scores attained on the five sub-tests of the Test of General Educational Development between the psychiatrically ill adult and the non-psychiatrically ill adult. A review of research literature did not reveal educational research studies that were directly pertinent to the study. Both the group of ill adults (43, ages 17 to 58) and the non-ill adults (143, ages 17 to 61) had successfully completed the Test of General Educational Development. The means of the two groups on the five sub-tests were analyzed by use of the t-test. Analysis of the data showed the following: (1) There is no significant difference in the mean scores of the two groups at the .05 level of significance on sub-test 1 (expression) and sub-test 2 (literature); and (2) There is a significant difference in the mean scores of the two groups at the .05 level of significance on sub-test 2 (social studies), 3 (natural science), and 5 (mathematics). (DB)