The goal of this grant is to determine if and when cancer risks can be estimated by establishing record-linkages between statewide cancer surveillance systems and occupational cohorts. More specifically, the aims of this study are to: (1) determine the feasibility of utilizing statewide cancer surveillance systems in the evaluation of cancer incidence within occupational cohorts; (2) compare and contrast the relative merits of standardized incidence ratios (SIR) with standardized mortality ratios (SMR) as determined from cancer surveillance systems incidence data and death certificate mortality data, respectively; and (3) provide recommendations concerning how and when statewide cancer surveillance systems should be utilized in the evaluation of occupational cohorts. SMR and SIR estimates will be calculated and compared for three occupational cohorts (e.g., Highway Maintenance, 3M, Conwed). SMR analyses have already been completed for the Highway Maintenance and 3M cohorts; a mortality update and SMR analysis will be conducted for the Conwed cohort (1988-1995). Cancer morbidity information, for the SIR analysis, will be determined by linking the three cohorts with the Minnesota Cancer Surveillance System (MCSS). Residency status will be required before person-years can be calculated, however, because inclusion in the MCSS is restricted to Minnesota residents. Linkages to other data sets will be used to determine the Minnesota residency status. Sensitivity analyses will be used to evaluate confounding and follow-up bias. Standardized mortality ratios will be compared to standardized incidence ratios for the Highway Maintenance, 3M, and Conwed cohorts. Finally, this study will evaluate the utility and limitations of cancer surveillance systems as a tool for occupational cancer research; recommendations for its use will be developed.