This proposal is a request for continuation of our multi-center, prospective cohort study that previously focused solely on Distal Upper Extremity (DUE) Disorders. The original study was in response to RFA OH-02-010 and involved 600+ workers in two diverse states. The study was funded for 4 years, ending September 2006. We are following 600+ workers in low (n=251), medium (n=249) and high (n=197) job physical exposure groups from 15+ different industries to improve generalizability of the study results. Preliminary analyses of the data suggest that our original objectives of the study will be met by September 2006. This proposed continuation application is for 3 additional years (seven years total). The main purposes of this continuing application are to: (1) continue monitoring upper limb disorders in this cohort for an additional 2.25 years to develop sufficient power to identify interactions within arid between job physical, individual and psychosocial factors, and (2) determine baseline prevalence rates and subsequent incidence rates over a 2.25 year period for specific shoulder disorders and symptoms for a broad range of exposures (initially classified as low, medium, and high). In addition to the original aims, this multi-center prospective cohort study will (1) study interactions within and between various risk factors (e.g. individual, psychosocial, and job physical factors) to better quantify risks for DUE musculoskeletal disorders (MSDs), (2) develop a comprehensive job analysis model including interactions for determining risk for DUE MSDs, (3) validate existing shoulder job analysis models (which are primarily based on posture), and (4) develop a comprehensive shoulder job analysis model for determining risk of shoulder MSDs. Job physical exposures primarily rely on measurements to quantify exposures to maximize objectivity and accuracy, while also utilizing methods that are practical and readily usable in industry [Research to Practice (r2p)]. All participants have health outcomes assessments by Certified Hand Therapists and qualified physicians. All subjects have: (i) baseline questionnaires, (ii) structured interviews, (iii) standardized physical examinations and (iv) nerve conduction studies (NCS). Changes in job physical exposures are monitored quarterly. Specific disorders and symptoms are assessed monthly on all participants using structured interviews and physical examinations. Those with paresthesias receive a follow-up NCS. Both Job Physical Exposure and Health Outcomes Assessment Teams are blinded to the other team. Multivariate logistic regression models and survival analyses will be utilized to explore relationships between risk factors (job physical, psychosocial and individual) and specific disorders, aggregate disorders and symptoms. In addition to quantifying ergonomic risk factors, interactions within and between various job physical, psychosocial and individual risk factors will be explored. This project is expected to result in DUE and shoulder job analysis models that have robust predictive capabilities for a broad range of jobs. ? ? ?