Comparison of papanicolaou (Pap) test rates across Ontario and factors associated with cervical screening.

BACKGROUND Cervical cancer remains a significant yet preventable disease despite the widespread availability of Pap test screening, which detects cervical cancer and its precursor lesions. The aims of this study were to: i) estimate and compare age- and hysterectomy-adjusted Pap test rates across the 37 Ontario public health units (PHUs), and ii) explore the association between several factors and Pap test rates (at the ecological level). METHODS Cytobase, an Ontario Pap test registry, captures more than 80% of all Pap tests in Ontario. Cytobase was used to determine Pap test rates adjusted for age, hysterectomy and Cytobase coverage for the year 2001. Multiple linear regression analyses were used to evaluate the relationship between Pap test rates and various factors at an ecological level, RESULTS Age-, hysterectomy- and Cytobase-adjusted one-year Pap rates ranged from 11.6% to 73.9% among PHUs. The overall rate for Ontario was 40.7%. Multivariate analyses indicated that the presence of a teaching hospital was associated with higher Pap test rates. CONCLUSION One-year Pap test rates varied greatly across the 37 public health units in Ontario. Pap test rates determined using Cytobase were lower than self-reported rates obtained from the Canadian Community Health Survey, possibly due to "over-reporting". In general, women were not screened as frequently as recommended by the Ontario Cervical Screening Program. A positive association was observed between Pap test rates and the presence of a teaching hospital. Data quality issues limit the ability to monitor cervical screening. A provincial registry would address these issues.