Quantitative estimates of the impact of sensitivity and specificity in mammographic screening in Germany.

Abstract

Study objective -To estimate quantitatively the impact of the quality of mammographic screening (in terms of sensitivity and specificity) on the effects and costs of nationwide breast cancer screening. Design -Three plausible "quality" scenarios for a biennial breast cancer screening programme for women aged 50-69 in Germany were analysed in terms of costs and effects using the Microsimulation Screening Analysis model on breast cancer screening and the natural history ofbreast cancer. Firstly, sensitivity and specificity in the expected situation (or "baseline" scenario) were estimated from a model based analysis of empirical data from 35 000 screening examinations in two German pilot projects. In the second "high quality" scenario, these properties were based on the more favourable diagnostic results from breast cancer screening projects and the nationwide programme in The Netherlands. Thirdly, a worst case, "low quality" hypothetical scenario with a 25% lower sensitivity than that experienced in The Netherlands was analysed. Setting -The epidemiological and social situation in Germany in relation to mass screening for breast cancer. Results -In the "baseline" scenario, an 11% reduction in breast cancer mortality was expected in the total German female population, ie 2100 breast cancer deaths would be prevented per year. It was estimated that the "high quality" scenario, based on Dutch experience, would lead to the prevention of an additional 200 deaths per year and would also cut the number of false positive biopsy results by half. The cost per life year gained varied from Deutsche mark (DM) 15 000 in the "high quality" scenario to DM 21000 in the "low quality" setting. Conclusions -Up to 20% of the total costs of a screening programme can be spent on quality improvement in order to achieve a substantially higher reduction in mortality and reduce undesirable side effects while retainiing the same cost effectiveness ratio as that estimated from the German data. (J7 Epidemiol Community Health 1997;51: 180-186) Breast cancer screening for women aged 50 and over is being implemented in a large number of European countries. These programmes aim to achieve a relatively high level of quality by means of strict organisation, training, and evaluation.'2 The definition of screening quality is often narrowed down to two propertiessensitivity (ie the capability of accurately detecting cancer at a screening examination and specificity (the ability to pinpoint accurately those women without breast cancer). High sensitivity can be assumed to be one of the key elements in achieving a reduction in breast cancer mortality, while high specificity will reduce the negative side effects of screening.3The nationwide programmes in the United Kingdom and The Netherlands have made a good start in providing facilities which ensure high standards. It is not certain, however, that these high standards can be achieved in all countries or programmes, especially where the organisation of screening is not centralised. Where screeni...

A modelling study to evaluate the costs and effects of lowering the starting age of population breast cancer screening

“…pronounced as compared to results from meta-analyses for older age groups [5][6]. On the other hand, there are also studies showing that potential harms as overdiagnosed breast cancers [7], radiation-induced breast cancer deaths [8,9], false positive test results [10][11][12][13][14][15], unnecessary biopsies [11,12], and costs of false positive biopsies [16] accompany regular screening, though their estimated numbers varied largely. Such potential harms have been considered to outweigh the benefits of regular screening for women 40-49 years old and thus regular breast cancer screening in this age group is generally not recommended [17].…”

Improvement in risk prediction, early detection and prevention of breast cancer in the NHS Breast Screening Programme and family history clinics: a dual cohort study

“…The analyses were based in a number of countries including the USA (n = 18 239,257,263,267,271,272,274,275,277,278,283,[289][290][291][292][293]295,298 ), the UK (n = 15 241,243,246,247,249,253,261,265,273,276,279,287,297,299,303 ), the Netherlands (n = 4 242,244,256,259 ), Hong Kong (n = 4 [304][305][306][307] ), Australia (n = 3 254,262,302 ), Italy (n = 3 245,251,252 ), Japan (n = 2 284,…”

The limited incorporation of economic analyses in clinical practice guidelines

“…The medical conditions with the most candidate practice guidelines and at least 10 candidate economic analyses for each category were acute myocardial infarction, 21–56 asthma, 57–90 smoking cessation, 91–113 colorectal cancer, 114–140 and breast cancer. 141–166 The second literature search with the addition of each condition's MESH heading resulted in the identification of additional guidelines and economic analyses. A total of 180 guidelines and 353 economic analyses were subjected to further review ( Fig.…”