Case-control studies in evaluating prostate cancer screening: an overview

Objectives: Ongoing randomized controlled screening trials for prostate cancer have not shown a beneficial effect on prostate cancer mortality reduction yet. A large number of observational (non-randomized) studies on prostate cancer screening have been published with contradictory outcome. This paper reviews the current case-control studies. Methods: Seven case-control studies of screening for prostate cancer were identified in a PubMed search, published from 1991 onwards, all conducted in North America. The screening test was either digital rectal examination (DRE) alone or in combination with PSA. Results: One DRE case-control study, found a significant preventive effect, whereas two others showed no effect of DRE screening on prostate cancer mortality nor on the occurrence of metastatic disease. Conflicting results were also observed in the studies assessing the effect of PSA/DRE. Only one study showed a significant 27% mortality reduction in the White male cohort, but found no effects in Blacks. The most recent study showed that screening with PSA/DRE was not protective in reducing prostate cancer mortality. Conclusions: Our review of the case-control studies does not indicate a benefit of prostate cancer screening. An answer has to come from the ERSPC trial, in Europe, and the PLCO trial, in the US, of which the outcomes are expected in 2007–2010. # 2006 European Association of Urolog

Screening for type 2 diabetes in a high-risk population: Study design and feasibility of a population-based randomized controlled trial

Background: We describe the design and present the results of the first year of a population-based study of screening for type 2 diabetes in individuals at high risk of developing the disease. High risk is defined as having abdominal obesity. Methods. Between 2006 and 2007, 79,142 inhabitants of two Dutch municipalities aged 40-74 years were approached to participate in screening. Eligible participants had a self-reported waist circumference of 80 cm for women and 94 cm for men, and no known pre-existing diabetes. Of the respondents (n=20,578; response rate 26%), 16,135 were abdominally obese. In total, 10,609 individuals gave written informed consent for participation and were randomized into either the screening (n=5305) or the control arm (n=5304). Participants in the screening arm were invited to have their fasting plasma glucose (FPG) measured and were referred to their general practitioner (GP) if it was 6.1 mmol/L. In addition, blood lipids were determined in the screening arm, because abdominal obesity is often associated with cardiovascular risk factors. Participants in both arms received written healthy lifestyle information. Between-group differences were analyzed with Chi-square tests and logistic regression (categorical variables) and unpaired t-tests (continuous variables). Results: The screening attendance rate was 84.1%. Attending screening was associated with age at randomization (OR=1.03, 95% CI 1.02-1.04), being married (OR=1.57, 95% CI 1.33-1.83) and not-smoking currently (OR=0.52, 95% CI 0.44-0.62). Of the individuals screened, 5.6% had hyperglycemia, and a further 11.6% had an estimated absolute cardiovascular disease risk of 5% or higher, according to the Systematic Coronary Risk Evaluation risk model. These participants were referred to their GP. Conclusions: Self-reported home-assessed waist circumference could feasibly detect persons at high risk of hyperglycemia or cardiovascular disease. Continuation of the large-scale RCT is warranted to test the hypothesis that targeted population-based screening for type 2 diabetes leads to a significant reduction in cardiovascular morbidity and mortality

Assessment of correlates of hand hygiene compliance among final year medical students: a cross-sectional study in the Netherlands

OBJECTIVES: To identify the factors that influence the hand hygiene compliance of final year medical students, using a theoretical behavioural framework. DESIGN: Cross-sectional survey assessing self-reported compliance and its behavioural correlates. SETTING: Internships of medical students in the Netherlands. PARTICIPANTS: 322 medical students of the Erasmus Medical Center were recruited over a period of 12 months during the Public Health internship, which is the final compulsory internship after an 18-month rotation schedule in all major specialities. PRIMARY AND SECONDARY OUTCOME MEASURES: Behavioural factors influencing compliance to hand hygiene guidelines were measured by means of a questionnaire based on the Theory of Planned Behaviour and Social Ecological Models. Multiple lin

Lead times and overdetection due to prostate-specific antigen screening: estimates from the European Randomized Study of Screening for Prostate Cancer

BACKGROUND: Screening for prostate cancer advances the time of diagnosis (lead time) and detects cancers that would not have been diagnosed in the absence of screening (overdetection). Both consequences have considerable impact on the net benefits of screening. METHODS: We developed simulation models based on results of the Rotterdam section of the European Randomized Study of Screening for Prostate Cancer (ERSPC), which enrolled 42,376 men and in which 1498 cases of prostate cancer were identified, and on baseline prostate cancer incidence and stage distribution data. The models were used to predict mean lead times, overdetection rates, and ranges (corresponding to approximate 95% confidence intervals) associated with different screening programs. RESULTS: Mean lead times and rates of overdetection depended on a man's age at screening. For a single screening test at age 55, the estimated mean lead time was 12.3 years (range = 11.6-14.1 years) and the overdetection rate was 27% (range = 24%-37%); at age 75, the estimates were 6.0 years (range = 5.8-6.3 years) and 56% (range = 53%-61%), respectively. For a screening program with a 4-year screening interval from age 55 to 67, the estimated mean lead time was 11.2 years (range = 10.8-12.1 years), and the overdetection rate was 48% (range = 44%-55%). This screening program raised the lifetime risk of a prostate cancer diagnosis from 6.4% to 10.6%, a relative increase of 65% (range = 56%-87%). In annual screening from age 55 to 67, the estimated overdetection rate was 50% (range = 46%-57%) and the lifetime prostate cancer risk was increased by 80% (range = 69%-116%). Extending annual or quadrennial screening to the age of 75 would result in at least two cases of overdetection for every clinically relevant cancer detected. CONCLUSIONS: These model-based lead-time estimates support a prostate cancer screening interval of more than 1 year

Landelijke evaluatie van bevolkingsonderzoek naar borstkanker in Nederland. 1990-2007 (XII). Het twaalfde evaluatierapport

Introduction: The last detailed report from the National Evaluation Team for Breast cancer screening (NETB) on the Dutch breast cancer screening programme appeared in 2005. It presented the screening results up until the end of 2003 which, however, were incomplete for some regions. The same applies to the two brief interim reports that were released in 2006 and 2007. The new evaluation report adds four reporting years to the entire evaluation period, i.e. those from 2004- 2007. The fact that this 12th report by the NETB is based on complete nationwide data on the screening activities of all nine screening regions is particularly good news. This is thanks to the additional efforts made by the two regions that had had a backlog of screened women’s follow-up data for years, enabling the backlog to be eliminated by spring 2009. It also enabled the optimum analysis of 18 years of national population research, and the presentation of the results without qualification. Unfortunately, this does not apply to the data on interval cancers which, subsequent to 1999, are far from being fully available at national level...