PURPOSE: To evaluate the effect of a resident study program involving the development of a repository based on program-specific high yield topics on the Council on Resident Education in Obstetrics and Gynecology (CREOG) In-Training Examination. BACKGROUND: A CREOG Test Item Summary Booklet may help improve CREOG test scores. METHODS: In 2012, obstetrics and gynecology residents at the University of Hawaii participated in a study program involving directed research based on selected high yield questions from the CREOG Test Item Summary Booklet. Questions were considered high yield if more than 75% of the program answered them incorrectly. Topics were assigned to each resident by the program director, researched and presented at monthly teaching sessions. They were then made assessable in a wiki website. The intervention was discontinued in 2013 due to lack of resident interest. Paired Student t tests and one-way analysis of variance were used to compare the differences in mean level-specific standardized scores over that 3-year period. Only scores of residents present for the entire 3-year study period were included. RESULTS: Eleven residents were present during the study period and sat for all three CREOG examinations. During the year of the study program, mean level-specific CREOG in-training examination standardized scores increased significantly compared with the prior year (194.7 compared with 208.2, P<.05). Scores decreased when the program was discontinued (201.6, P<.05). DISCUSSION: These findings demonstrate that the CREOG Test Item Summary Booklet can be used to effectively direct educational efforts resulting in improvements in CREOG examination performance.