Background: Regional Cervical Screening Quality Assurance Reference Centres maintain and improve the quality of their local cervical screening programmes by monitoring standards based on a range of outcome measures. The classification of invasive cervical cancer screening histories can aid the interpretation of cervical cancer incidence trends in cervical screening services.
Methods: Cervical cancer incidence rates were calculated for cytology laboratory catchment areas, which reflected where local general practitioners sent cervical samples.
Objectives: To examine the ability of existing classification systems to provide screening histories for invasive cervical cancers which can be used in the evaluation of the NHS Cervical Screening Programme (NHSCSP), and to provide the diagnostic route data item required for the National Cancer Data Set (NCDS).
Methods: The ability of existing classification systems to derive unique, consistent screening histories for a cohort of invasive cervical cancers diagnosed in the West Midlands region in the period 2000-03 was tested using two separate timelines for women on normal routine recall (usually 3 or 5 years) and those on early recall having had an inadequate, low-grade abnormal or negative smear.
Results: Neither of the existing classification systems was capable of adequately categorizing all invasive cervical cancers.