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BACKGROUND The aim of this study was to evaluate the ability of human spermatozoa to penetrate methylcellulose (MC) and to compare this with penetration in hyaluronic acid. METHODS Spermatozoa from normal (>or=20 x 10(6) sperm/ml, >or=50% progressive motility, >or=5% normal forms) and oligozoospermic (<20 x 10(6) sperm/ml) semen samples were allowed to(More)
OBJECTIVE To investigate change in mental health after smoking cessation compared with continuing to smoke. DESIGN Systematic review and meta-analysis of observational studies. DATA SOURCES Web of Science, Cochrane Central Register of Controlled Trials, Medline, Embase, and PsycINFO for relevant studies from inception to April 2012. Reference lists of(More)
BACKGROUND Cluster randomised controlled trials (CRCTs) are frequently used in health service evaluation. Assuming an average cluster size, required sample sizes are readily computed for both binary and continuous outcomes, by estimating a design effect or inflation factor. However, where the number of clusters are fixed in advance, but where it is possible(More)
Additional material is published online only. To view please visit the journal online The stepped wedge cluster randomised controlled trial is a relatively new study design that is increasing in popularity. It is an alternative to parallel cluster trial designs, which are commonly used for the evaluation of service delivery or policy interventions delivered(More)
BACKGROUND The possibility of conception following selective salpingography and tubal catheterization is believed to decline sharply a few months after the procedure. This observation may be due to the relatively small number of patients and short follow-up of previous studies. Furthermore, couples with other causes of infertility apart from proximal tubal(More)
Stepped-wedge cluster randomised trials (SW-CRTs) are being used with increasing frequency in health service evaluation. Conventionally, these studies are cross-sectional in design with equally spaced steps, with an equal number of clusters randomised at each step and data collected at each and every step. Here we introduce several variations on this design(More)
OBJECTIVES The headroom approach to medical device development relies on the estimation of a value-based price ceiling at different stages of the development cycle. Such price-ceilings delineate the commercial opportunities for new products in many healthcare systems. We apply a simple model to obtain critical business information as the product proceeds(More)
OBJECTIVE To determine whether cognitive impairment is associated with changes in self-care behaviour and use of health and social services in older subjects with diabetes mellitus. RESEARCH DESIGN AND METHODS This was a community based, case-control study of subjects registered with general practices participating in the All Wales Research into Elderly(More)
OBJECTIVE The quality of clinical care is often assessed by retrospective examination of case-notes (charts, medical records). Our objective was to determine the inter-rater reliability of case-note audit. METHODS We conducted a systematic review of the inter-rater reliability of case-note audit. Analysis was restricted to 26 papers reporting comparisons(More)
OBJECTIVES To conduct an independent evaluation of the first phase of the Health Foundation's Safer Patients Initiative (SPI), and to identify the net additional effect of SPI and any differences in changes in participating and non-participating NHS hospitals. DESIGN Mixed method evaluation involving five substudies, before and after design. SETTING NHS(More)