Surveillance for equity in cervical cytology screening

Background. The opportunistic basis on which screening has been conducted in South Africa has resulted in multiple rescreening of a small proportion of the population (which excludes most women at high risk) and low population coverage. There has consequently been a failure of screening to impact on the incidence of cervical cancer in most of the population. Aim. To propose the use of the ratio of smears showing cervical intra-epithelial neoplasia (CIN) III :smears showing signs of malignancy as an indicator for the surveillance of equity in cervical cytology screening, and to apply this indicator to an area of the Western Cape of South Africa. Results. Marked inequity in screening is demonstrated between metropolitan and non-metropolitan areas, and between different non-metropolitan districts. Inequity in screening between different age groups of women is also found, and this is associated with an inappropriately young age distribution of screening activity. Conclusion. The application of this indicator in the routine surveillance of screening activity may be useful in monitoring progress towards the implementation of more equitable screening programmes, and the validity of the indicator should be tested in other settings.