Belinda J. Hall

‘Scoping the scope’ of a cochrane review

Systematic reviews use a transparent and systematic process to define a research question, search for studies, assess their quality and synthesize findings qualitatively or quantitatively. A crucial step in the systematic review process is to thoroughly define the scope of the research question. This requires an understanding of existing literature, including gaps and uncertainties, clarification of definitions related to the research question and an understanding of the way in which these are conceptualized within existing literature. This information is often acquired in an ad hoc fashion, however a useful and increasingly popular way to collect and organize important background information and develop a picture of the existing evidence base is to conduct a scoping review. Such reviews may be published as a research outcome in their own right and are appealing since they produce a broad map of the evidence that, if sufficiently transparent and widely available via publication, can be used by many and for applications beyond the authors originally intended purpose. Scoping reviews can inform a systematic review, particularly one with a very broad topic scope, such as those edited by the Cochrane Public Health Group.

Essential components of public health evidence reviews: capturing intervention complexity, implementation, economics and equity

Carefully developed recommendations for conducting studies of programme effectiveness have provided an extremely useful framework for researchers and articulated the different components required to answer not only the question of effectiveness (does it work?), but also the equally important questions of how, why and for whom was the programme effective. However, the continued emphasis on the use of the term ‘complex’ in describing the intervention itself or the system within which it is contextualized can detract from our ability to focus on the strategies required to better understand the strengths or limitations of the evidence base for decision-making. Social and public health interventions operate in a context that demands explicit recognition of politics, service systems, funding flows and shortages, staff competencies and multi-strategic approaches. For those immersed in the complicated political and scientific acrobatics of coordinating studies of programme implementation and evaluation, any real or perceived misalignment in the connection between research effectiveness trials versus policy relevant implementation knowledge must be overcome. Devising relatively simple approaches to understand complexity can assist in making complexity more manageable so that meaningful answers to important policy and practice questions can emerge. In this paper we argue that if reviews of intervention evidence are to be useful to decision-makers at all, contextual and implementation information is an essential, nonnegotiable component of the review process. We highlight steps evidence review authors can take to capture and interpret this information. With relatively small changes or additions to the evidence review process, practical, meaningful and rigorous public health evidence can be generated. Practical steps for embracing complexity and ensuring policy relevance

Reviewing interventions delivered to whole communities: learnings and recommendations for application to policy, practice and evidence development

*This article is free to read on the publishers website* Several reviews within The Cochrane Library address interventions designed to promote physical activity and exercise.1–3 Interventions investigated in these reviews have generally sought to increase the physical activity of individuals or specific groups of people. A new review published by the Cochrane Public Health Group entitled ‘Community-wide Interventions for Increasing Physical Activity’,4 examines the effectiveness of interventions that aim to improve the physical activity levels of an entire community. We were particularly interested in understanding the effectiveness of such approaches, but also whether they have an impact on inequalities, have potential to be sustainable and are cost-effective. In doing so, one of the most important contributions of this review is considerations and recommendations for the advancement of methods for developing, conducting and evaluating complex interventions, and seeking to synthesize findings relevant for programme development and policy-making. This paper briefly highlights some of these issues.

Managing the production of a Cochrane systematic review

Undertaking a Cochrane systematic review can be an incredibly rewarding experience. It is however a challenging and time-consuming task. The Cochrane Handbook for Systematic Reviews of Interventions1 provides an essential resource to help reviewers navigate the often complex methodological issues of systematic review research. Additional guidelines have been developed for those undertaking reviews of public health topics,2 and Cochrane Centres throughout the world offer invaluable training opportunities. This emphasis on training and methodological rigour has helped Cochrane reviews become one of the most respected sources of synthesized research available. Even with the assistance available, however, many authors with good intentions register titles and prepare protocols but fail to publish the completed review. Data extracted from Cochrane’s Information Management System (Archie) in June 2010 showed that there were 1,301 titles registered more than two years ago that have not been published as a full review.3 Of these registered titles, 697 have had protocols published (25 are no longer active) while 604 have not even progressed to this stage (154 are no longer active). There are also 146 protocols that have been published for more than two years without being converted into completed reviews. These registered titles and protocols that have not yet progressed to a completed review represent a significant amount of time and energy invested by review authors, Cochrane editorial staff and, in some cases, external referees...

Snakes and ladders: challenges and highlights of the first review published with the Cochrane Public Health Review Group

The Cochrane Public Health Review Group (PHRG) published its first systematic review on 17 February 2010. This review, which examined flexible working conditions and their effects on employee health and wellbeing, addressed one of the key principles of action outlined in the World Health Organization’s Commission on the Social Determinants of Health, namely to ‘improve the conditions of daily life—the circumstances in which people are born, grow, live, work, and age’ (p. 3). It also serves to illustrate some of the thorny issues to be negotiated in a review of a complex public health intervention. Our review evaluated the effects (benefits and harms) of flexible working interventions on the physical, mental and general health and wellbeing of employees and their families. We also aimed to examine whether any benefits or harms are differentially experienced by gender, age, ethnicity, occupation or socio-economic status. Our review included 10 studies of 6 different types of flexible working and it tentatively concluded that flexible working interventions that increase worker control and choice (such as self-scheduling of working hours or gradual/partial retirement) are likely to have a positive effect on health outcomes. The release of this review attracted considerable media attention, a tangible indicator of the level of public interest in this topic. This also represents a potential means for increasing the utility of evidence, of which systematic reviews are an important part, in the decision-making process. The full results are published in The Cochrane Library. In this paper we discuss three issues highlighted by the current review and the implications for those striving to build the evidence base in this area: (i) a paucity of studies of a high-quality design; (ii) a lack of data on implementation or motivation for the interventions and (iii) a dearth of evidence on differential effects of the interventions to understand the potential impacts on health inequalities.

Enhancing capacity for ‘systematic’ thinking in public health

The concept of being evidence based or evidence informed is widely acknowledged as an important component of decision-making. It is perhaps most universally referred to in medicine, however has extended into many other disciplines over the past decade, including public health. Evidence-based public health has been defined as the ‘conscientious, explicit and judicious use of current best evidence in making decisions about the care of communities and populations in the domain of health protection, disease prevention, health maintenance and improvement (health promotion)’.1 More recent literature favours the use of the term evidence informed over evidence based to acknowledge the varying influences on decisions in this complex field.2,3 Evidence-informed activities in any discipline require a specific set of skills in critical thinking. These skills include identifying the questions to be resolved, collecting relevant evidence, and assessing, synthesizing and distilling evidence in a way that can inform the set of activities to be undertaken as a result.