The applicant's broad goals are to further develop research skills, become an independent researcher, and become an accomplished educator in occupational safety and health. The Special Emphasis Research Career Award allow the applicant to take advantage of the excellent resources available at the University of Iowa including comprehensive research support services, exceptional mentoring and collaboration with independent researchers in occupational health, and advanced coursework in the Department of Preventive Medicine and Environmental Health. The applicant proposes a cross-sectional study to characterize the prevalence of carpal tunnel syndrome (CTS) among construction apprentices. Data will be collected from 350 construction apprentices that have low exposure to hand and wrist-intensive work (operating engineers) and compared to previously collected data from 430 apprentices in trades that are associated with high exposure to hand and wrist-intensive work (sheet metal, electrical, plumbing workers). Apprentices in the operating engineering trade have a very similar demographic background to the existing cohort and will serve as a comparison group. Electrophysiologic tests and hand symptoms will be used to identify CTS cases among the operating engineer apprentices. Questionnaires will be utilized to determine occupational factors, personal factors, and medical histories associated with CTS. Focus group meetings will be held to determine why many apprentices do not seek medical attention for CTS symptoms. Additionally, electrophysiologic tests and questionnaires will be repeated in the apprentices in two years to assess changes in electrophysiologic variables and symptoms. The data collected in the proposed study will provide a better understanding of the specific work factors associated with CTS, provide pilot data for planning future projects to study the natural history of CTS, and assist in the development of strategies for the prevention of CTS in construction and non-construction workplaces. The proposed research study directly addresses the issue of musculoskeletal disorders of the upper extremity and assists in accomplishing the goals set out in the National Occupational Research Agenda.