Andrew J. Stevens

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OBJECTIVE To assess the validity of case mix adjustment methods used to derive standardised mortality ratios for hospitals, by examining the consistency of relations between risk factors and mortality across hospitals. DESIGN Retrospective analysis of routinely collected hospital data comparing observed deaths with deaths predicted by the Dr Foster Unit(More)
Because of the recent and controversial example of sham surgery for the evaluation of fetal tissue transplants for Parkinson's disease, there is renewed interest in the ethics of using "active" placebos in surgical trials, where otherwise there are no inert procedures available, and in pharmacological trials, where there are inert substances, but where(More)
BACKGROUND Although acute hospitals offer a twenty-four hour seven day a week service levels of staffing are lower over the weekends and some health care processes may be less readily available over the weekend. Whilst it is thought that emergency admission to hospital on the weekend is associated with an increased risk of death, the extent to which this(More)
BACKGROUND AND OBJECTIVE Utilities (values representing preferences) for healthcare priority setting are typically obtained indirectly by asking patients to fill in a quality of life questionnaire and then converting the results to a utility using population values. We compared such utilities with those obtained directly from patients or the public. (More)
Randomised controlled trials (RCTs) play a central role in modern medical advance, and they require participants who understand and accept the procedures involved. Published evidence suggests that RCT participants often fail to understand that treatments are allocated at random and that clinicians are in equipoise about which treatment is best. We examine(More)
The frequency of visits to Emergency Departments (ED) varies greatly between populations. This may reflect variation in patient behaviour, need, accessibility, and service configuration as well as the complex interactions between these factors. This study investigates the relationship between distance, socio-economic deprivation, and proximity to an(More)
OBJECTIVE To describe trends in new drugs launched in the UK from 1982 to 2011 and test the hypothesis that the rate of new drug introductions has declined over the study period. There is wide concern that pharmaceutical innovation is declining. Reported trends suggest that fewer new drugs have been launched over recent decades, despite increasing(More)
BACKGROUND Cardiac rehabilitation following myocardial infarction reduces subsequent mortality, but uptake and adherence to rehabilitation programmes remains poor, particularly among women, the elderly and ethnic minority groups. Evidence of the effectiveness of home-based cardiac rehabilitation remains limited. This trial evaluates the effectiveness and(More)
BACKGROUND Concerns have been raised about low participation rates of people from minority ethnic groups in clinical trials. However, the evidence is unclear as many studies do not report the ethnicity of participants and there is insufficient information about the reasons for ineligibility by ethnic group. Where there are data, there remains the key(More)
Evaluations of service delivery interventions with contemporaneous controls often yield null results, even when the intervention appeared promising in advance. There can be many reasons for null results. In this paper we introduce the concept of a 'rising tide' phenomenon being a possible explanation of null results. We note that evaluations of service(More)