The advantage of using the between approach to set targets and monitor progress is that it mirrors the long used and familiar health inequality measure of the standardised mortality ratio. However, we join Shaw et al in questioning whether this conventional approach is fit for purpose.Most descriptions of the national inequality targets do not specify whether the reductions required are relative or absolute, as if it does not matter. We have shown why it does matter. Moreover, lack of transparency in this regard has led to the inconsistent use of relative and absolute gaps in government targets going unquestioned. It has also resulted in confusion over how to establish local health improvement targets that are consistent with national policy on reducing health inequalities. Research methods Reporting attrition in randomised controlled trialsJo C Dumville, David J Torgerson, Catherine E Hewitt Loss to follow-up can greatly affect the strength of a trial's findings. But most reports do not give readers enough information for them to be able to understand the potential effects

A comprehensive review of current evidence found some evidence that preoperative skin preparation with 0.5% chlorhexidine in methylated spirits was associated with lower rates of SSIs following clean surgery than alcohol-based povidone iodine paint. However this single study was poorly reported. Practitioners may therefore elect to consider other characteristics such as costs and potential side effects when choosing between alternatives.The design of future trials should be driven by the questions of high priority to decision makers. It may be that investment in at least one large trial (in terms of participants) is warranted in order to add definitive and hopefully conclusive data to the current evidence base. Ideally any future trial would evaluate the iodine-containing and chlorhexidine-containing solutions relevant to current practice as well as the type of solution used (alcohol vs. aqueous).

Background Indications for the use of negative pressure wound therapy (NPWT) are broad and include prophylaxis for surgical site infections (SSIs). While existing evidence for the effectiveness of NPWT remains uncertain, new trials necessitated an updated review of the evidence for the effects of NPWT on postoperative wounds healing by primary closure. Objectives To assess the effects of negative pressure wound therapy for preventing surgical site infection in wounds healing through primary closure. Search methods We searched the Cochrane Wounds Specialised Register, CENTRAL, Ovid MEDLINE (including In-Process & Other Non-Indexed Citations), Ovid Embase, and EBSCO CINAHL Plus in February 2018. We also searched clinical trials registries for ongoing and unpublished studies, and checked reference lists of relevant included studies as well as reviews, meta-analyses, and health technology reports to identify additional studies. There were no restrictions on language, publication date, or setting. Selection criteria We included trials if they allocated participants to treatment randomly and compared NPWT with any other type of wound dressing, or compared one type of NPWT with another type of NPWT. Data collection and analysis Four review authors independently assessed trials using predetermined inclusion criteria. We carried out data extraction, 'Risk of bias' assessment using the Cochrane 'Risk of bias' tool, and quality assessment according to GRADE methodology.

Background Pressure ulcers (i.e. bedsores, pressure sores, decubitus ulcers) are areas of localised damage to the skin and underlying tissue. They are common in the elderly and immobile, and costly in financial and human terms. Pressure-relieving support surfaces (i.e. beds, mattresses, seat cushions etc) are used to help prevent ulcer development. Objectives This systematic review seeks to establish: (1) the extent to which pressure-relieving support surfaces reduce the incidence of pressure ulcers compared with standard support surfaces, and, (2) their comparative effectiveness in ulcer prevention.