The purpose of the analyses reported in this paper was to compare performance on the GED (General Educational Development) Tests, U.S. edition, across three groups of examinees: (a) graduating high school seniors in the GED Tests U.S. 2001 norm group, (b) GED Tests candidates who took one or more tests in the U.S. in 2002-2004, and (c) GED Tests candidates who passed the tests in the U.S. in 2002-2004. By comparing graduating high school seniors and GED Tests examinees, this report provides evidence of the academic value of the GED Tests credential. This report also identifies several academic content and cognitive levels in which GED Tests examinees are likely to have difficulties. Performance of the three groups was compared through comparison of standard scores, percentile rank distributions, and item difficulty statistics for the tests and each of the content and cognitive levels measured by the GED Tests. The results should be useful primarily to employers and admissions officers evaluating applicants who have a credential based on passing the GED Tests. Additionally, adult education administrators and teachers should find this information useful when planning and developing instructional programs for GED Tests candidates. A glossary is appended. (Contains 10 tables, 2 figures, and 2 footnotes.) [For the executive summary, see ED510055.]