The Ontario cancer incidence survey, 1964-1966: a new approach to cancer data acquisition.

The Ontario Cancer Incidence Survey of 1964-1966 proved that records already collected for other purposes can be linked to provide satisfactory incidence data with minimal duplication of effort. The survey yielded information on 81,155 malignant neoplasms; the 1966 incidence rate was 316.7 per 100,000 Ontario residents. Advantages of this system over orthodox registries are respectable geographic coverage and follow-up without reporting by physicians, and the full use of accumulated material. Disadvantages are the time-lag inherent in using service records submitted for other purposes, and initial difficulty in distinguishing between new and old cases. The problem of inadequate reporting of pathology on hospital separation forms is being solved. Survey tabulations are frequently used. The survey methods have been adapted for computer processing as an on-going provincial cancer registry.