A framework for quantifying net benefits of alternative prognostic models
Rapsomaniki E., White IR., Wood AM., Thompson SG., Tipping RW., Ford CE., Simpson LM., Folsom AR., Chambless LE., Panagiotakos DB., Pitsavos C., Chrysohoou C., Stefanadis C., Knuiman M., Whincup PH., Wannamethee SG., Morris RW., Kiechl S., Willeit J., Oberhollenzer F., Mayr A., Wald N., Lawlor DA., Yarnell JW., Gallacher J., Casiglia E., Tikhonoff V., Nietert PJ., Sutherland SE., Bachman DL., Keil JE., Cushman M., Tracy R., Tybjærg-Hansen A., Nordestgaard BG., Frikke-Schmidt R., Giampaoli S., Palmieri L., Panico S., Vanuzzo D., Pilotto L., Gómez de la Cámara A., Gómez Gerique JA., Simons L., McCallum J., Friedlander Y., Lee AJ., Taylor J., Guralnik JM., Wallace R., Guralnik JM., Blazer DG., Guralnik JM., Guralnik JM., Khaw KT., Schöttker B., Müller H., Rothenbacher D., Jansson JH., Wennberg P., Nissinen A., Donfrancesco C., Salomaa V., Harald K., Jousilahti P., Vartiainen E., Woodward M., D'Agostino RB., Wolf PA., Vasan RS., Pencina MJ., Bladbjerg EM., Jørgensen T., Møller L., Jespersen J., Dankner R., Chetrit A., Lubin F., Rosengren A., Lappas G., Eriksson H., Björkelund C., Lissner L., Bengtsson C., Nagel D., Kiyohara Y., Arima H., Doi Y., Ninomiya T., Rodriguez B., Dekker JM., Nijpels G., Stehouwer CDA., Iso H., Kitamura A., Yamagishi K., Noda H., Goldbourt U.
New prognostic models are traditionally evaluated using measures of discrimination and risk reclassification, but these do not take full account of the clinical and health economic context. We propose a framework for comparing prognostic models by quantifying the public health impact (net benefit) of the treatment decisions they support, assuming a set of predetermined clinical treatment guidelines. The change in net benefit is more clinically interpretable than changes in traditional measures and can be used in full health economic evaluations of prognostic models used for screening and allocating risk reduction interventions. We extend previous work in this area by quantifying net benefits in life years, thus linking prognostic performance to health economic measures; by taking full account of the occurrence of events over time; and by considering estimation and cross-validation in a multiple-study setting. The method is illustrated in the context of cardiovascular disease risk prediction using an individual participant data meta-analysis. We estimate the number of cardiovascular-disease-free life years gained when statin treatment is allocated based on a risk prediction model with five established risk factors instead of a model with just age, gender and region. We explore methodological issues associated with the multistudy design and show that cost-effectiveness comparisons based on the proposed methodology are robust against a range of modelling assumptions, including adjusting for competing risks. © 2011 John Wiley & Sons, Ltd.