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Research article:

Breast and cervical cancer screening utilization, and recording bias, in women with type 2 diabetes (UK)


Matthew Carr, Evan Kontopantelis, Tim Doran, Christine Campbell, Lorraine Lipscombe, Emma Crosbie, Anthony Howell, Iain E Buchan, Andrew G Renehan (2015) Breast and cervical cancer screening utilization, and recording bias, in women with type 2 diabetes (UK). Diabetologia, doi:

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Aims/hypothesis: Studies from healthcare databases suggest that patients with type 2 diabetes (T2D) under-utilize cancer screening opportunities, but recording bias may be a problem. We evaluated the relative effect of T2D on screening utilization trends among long-established UK national programmes in breast and cervical cancers; and tested the impact of introducing a primary care financial incentive scheme (QOF) in 2004, known to improve data recording for diabetes-related care. Materials and methods: Using the Clinical Practice Research Datalink, we identified women with prevalent T2DM (N = 174,256), separately by year for 1999 to 2011, and eligible for screening events for breast (aged 50-70 years) and cervical (aged 35-49 and 50-64 years) cancers. We described secular trends and compared these with the non-diabetes population, and accounted for co-morbidities using matched conditional logistic regression models. We performed interrupted time-series (ITS) analyses to assess the impact of the QOF introduction. Results: Compared with the non-diabetes population, relative uptake rates for breast and cervical screening were generally similar in patients with T2D pre-2004, becoming greater for years post-2004. These patterns were unaffected by adjustment for GP practice, and were not accounted for by T2D associated co-morbidities. ITS analysis showed increased activities in all three screening groups for 2007, but these broadly returned to pre-2004 trends by 2011, paralleling similar patterns in recording for other care provision indicators. Conclusions/interpretation: In this population, we found no evidence that women with T2D under-utilize breast and cervical cancer screening opportunities. A financial incentive scheme was associated with intermediate-term improvements in screening utilization, but this is likely to reflect improved recording of care events.
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Andrew Renehan
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Res22: screen_cervical Download this codelist
Res22: diabetes_meds Download this codelist
Res22: diabetes Download this codelist
Res22: screen_breast Download this codelist

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