Effect of screening on incidence of and mortality from cancer of cervix in England: evaluation based on routinely collected statistics.

OBJECTIVE To assess the impact of screening on the incidence of and mortality from cervical cancer. DESIGN Comparison of age specific incidence and mortality before and after the introduction of the national call and recall system in 1988. SETTING England. SUBJECTS Women aged over 19 years. RESULTS From the mid-1960s, the number of smears taken rose continuously to 4.5 million at the end of the 1980s. Between 1988 and 1994, coverage of the target group doubled to around 85%. Registrations of in situ disease increased broadly in parallel with the numbers of smears taken. The overall incidence of invasive disease remained stable up to the end of the 1980s, although there were strong cohort effects; from 1990 incidence fell continuously and in 1995 was 35% lower than in the 1980s. The fall in overall mortality since 1950 accelerated at the end of the 1980s; there were strong cohort effects. Mortality in women under 55 was much lower in the 1990s than would have been expected. CONCLUSIONS The national call and recall system and incentive payments to general practitioners increased coverage to around 85%. This resulted in falls in incidence of invasive disease in all regions of England and in all age groups from 30 to 74. The falls in mortality in older women were largely unrelated to screening, but without screening there might have been 800 more deaths from cervical cancer in women under 55 in 1997.