Manuela Quaresma and Bernard Rachet
Funnel plots were developed to enable comparison of institutional performance whilst showing the precision of each measure. We first used them to show variation between surgeons and over time in the proportion of women referred for radiotherapy after breast cancer, for a Panorama documentary broadcast in 2006. We also used them to show differences in the excess hazard of death from breast cancer among women managed by different surgeons.
We have developed funnel plots to improve the visualisation of geographical and temporal patterns in cancer survival for health policy-makers. A tutorial paper describes the use of these plots for various measures, such as relative survival and the excess hazard of death (Quaresma et al., 2014). We also set out new statistical formulations of the control limits for each of these measures.
We have also developed smoothed maps to improve the presentation and interpretation of the results for national strategic purposes, as well as for local management.
References and further reading
Quaresma, M., Coleman, M. P. & Rachet, B. Funnel plots for population-based cancer survival: principles, methods and applications. Statistics in Medicine 2014; 33: 1070-1080.
Rachet B, Maringe C, Nur U, Quaresma M, Shah A, Woods LM, Ellis L, Walters S, Forman D, Steward JA, Coleman MP. Population-based cancer survival trends in England and Wales up to 2007: an assessment of the NHS cancer plan for England. Lancet Oncol 2009; 10 : 351-69
Ito Y, Ioka A, Tsukuma H, Ajiki W, Sugimoto T, Rachet B, Coleman MP. Regional differences in population-based cancer survival between six prefectures in Japan: application of relative survival models with funnel plots. Cancer Sci 2009; 100: 1306-11
Coleman MP, Quaresma M, Berrino F, Lutz J-M, De Angelis R, Capocaccia R, Baili P, Rachet B, Gatta G, Hakulinen T, Micheli A, Sant M, Weir HK, Elwood JM, Tsukuma H, Koifman S, Azevedo e Silva G, Francisci S, Santaquilani M, Verdecchia A, Storm HH, Young JL, CONCORD Working Group. Cancer survival in five continents: a worldwide population-based study (CONCORD). Lancet Oncol 2008; 9: 730-56
Coleman MP, Rachet B, Quaresma M, Lepage C, Baum M, Sikora K. Bradford NHS Trust and Panorama [webappendix report, 119pp]. Lancet 2006, 368: 730-731
Coleman MP, Rachet B, Quaresma M, Lepage C, Baum M, Sikora K. Bradford NHS Trust and Panorama. Lancet 2006; 368: 730-1
Spiegelhalter DJ. Funnel plots for comparing institutional performance. Stat Med 2005; 24: 1185-202