Cluster-randomised trial of risk communication to enhance informed uptake of cervical screening.

Background: Women overestimate both population and individual risk of cervical cancer. This may contribute to the recognised excess screening frequency for low-risk women.

Aim: To investigate whether an individualized risk communication package could affect stated preferences for screening interval and actual screening behaviour.

Design: Pragmatic, practice-based cluster randomised controlled trial.

Setting: Twenty-nine practices (15 intervention, 14 control) in North Wales recruited 1890 women attending for cervical smears.

Method: A risk communication package containing visual material was compared with normal practice. Practice nurses received training in its delivery. The short-term primary outcome was stated preference for screening interval; the long-term primary outcome was actual screening behaviour.

Results: In the short term, intervention arm women were significantly less likely to prefer a shorter than recommended interval (odds ratio [OR] = 0.51, 95% confidence interval [CI] = 0.41 to 0.64; P < 0.0001). At the five-year follow-up, fewer women in the intervention arm had attended for screening sooner than their recommended recall. The magnitude of difference in excess screening interval preference and behaviour was similar, but behaviour had a wider confidence interval and a marginally non-significant P-value (OR = 0.61, 95% CI = 0.36 to 1.03; P = 0.063). Better knowledge and more accurate risk perceptions were demonstrated, with an improvement in measures of anxiety. The extra cost per woman receiving the intervention was 6 Pounds.

Conclusions: Women's perception of risk contributes to determining screening intervals in addition to practice factors. Simple risk information delivered in primary care affected women's stated preferences for tests. The impact on actual screening behaviour was more equivocal. Overall, the intervention showed a substantial benefit and any disbenefit can be ruled out. This approach to providing risk information could, at low cost, benefit other screening programmes and may relieve anxiety.