Primary care physician characteristics associated with cancer screening: a retrospective cohort study in Ontario, Canada

Importance — Primary care physicians can serve as both facilitators and barriers to cancer screening, particularly for under-screened groups such as immigrant patients.

Objective — To inform physician-targeted interventions by identifying primary care physician characteristics associated with cancer screening for their eligible patients, for their eligible immigrant patients, and for foreign-trained physicians, for their eligible immigrant patients from the same world region. Design: A population-based retrospective cohort study, looking back three years from December 31, 2010.

Setting — Urban primary care practices in Ontario, Canada’s largest province.

Participants — 6,303 physicians serving 1,156,627 women eligible for breast cancer screening, 2,730,380 women eligible for cervical screening, and 2,260,569 patients eligible for colorectal screening.

Outcomes — Appropriate breast screening was defined as at least one mammogram in the previous two years, appropriate cervical screening was defined as at least one Pap test in the previous three years, and appropriate colorectal screening as at least one fecal occult blood test in the previous two years or at least one colonoscopy or barium enema in the previous ten years.

Results — Just fewer than 40% of physicians were female, and 26.1% were foreign-trained. In multivariable analyses, physicians who attended medical schools in the Caribbean/Latin America, the Middle East/North Africa, South Asia, and Western Europe were less likely to screen their patients than Canadian graduates. South Asian-trained physicians were significantly less likely to screen South Asian women for cervical cancer than other foreign-trained physicians who were seeing region-congruent patients (adjusted odds ratio: 0.56 [95% confidence interval 0.32-0.98] versus physicians from the USA, Australia and New Zealand). South Asian patients were the most vulnerable to under-screening, and decreasing patient income quintile was consistently associated with lower likelihood of screening, although less so for immigrant patients.

Conclusions and Relevance — This study highlights certain physician characteristics that are associated with cancer screening for eligible patients, including immigrant patients, and that should be considered when designing physician-targeted interventions. The researchers have also highlighted an ethnic community, South Asians, which requires particular attention, both among its patients and its primary care providers. Future research should further explore the reasons for these findings.