Evaluating the effectiveness of public health interventions: the role and activities of the Cochrane Collaboration

Public health decision makers, funders, practitioners, and the public are increasingly interested in the evidence that underpins public health decision making. Decisions in public health cover a vast range of activities. With the ever increasing global volume of primary research, knowledge and changes in thinking and approaches, quality systematic reviews of all the available research that is relevant to a particular practice or policy decision are an efficient way to synthesise and utilise research efforts. The Cochrane Collaboration includes an organised entity that aims to increase the quality and quantity of public health systematic reviews, through a range of activities. This paper aims to provide a glossary of the terms and activities related to public health and the Cochrane Collaboration.

The role and theoretical evolution of knowledge translation and exchange in public health

Background There is an increased emphasis in public health research on effective models and strategies to support knowledge translation (KT), the exchange, synthesis and ethically sound application of research findings within a complex set of interactions among researchers and knowledge users. In other words, KT can be seen as an acceleration of the knowledge cycle—an acceleration of the natural transformation of knowledge into use (Canadian Institutes of Health Services Research. Knowledge Translation Strategy, 2004). The most recent conceptualizations consider the complexities of public health decision-making. The role of practitioners and communities is increasingly considered.

Methods We identify, describe and discuss the theoretical underpinnings of KT and recommend a way forward to build the evidence for more effective practice.

Results Theoretical perspectives increasingly influence research on KT in public health. A range of innovative work is being conducted to explore methods for KT using practical tools, often with the support of government.

Conclusions KT describes a crucial and to date under-developed element of the research process. There is an important gap in theoretically informed empirical studies of effectiveness of proposed approaches in public health, health promotion and preventive medicine, and thus much of the debate remains abstract. There is clearly an urgent policy need to establish the effectiveness of KT models in a range of contexts. This must include both the consideration of development and the utilization of knowledge.

Local health policy development processes in the Netherlands: an expanded toolbox for health promotion

Although much research has been done on the existence and formation of risk and issue based health policies, there is only little insight in health policy development processes in a broader context. This hampers intervention in these policy processes to adequately develop integrated and effective health policies.

Legislation in the Netherlands requires municipalities to develop and implement local health policies. These policies are supposed to aim at the promotion of health across sectors and with a strong community involvement. Health policy development processes have been studied in four Dutch municipalities. For each case, we identified a range of stakeholders and monitored the change or stability of their characteristics over 3 years. In addition, for each case, three overlaying maps of networks were made addressing communication and collaboration actions within the defined set of stakeholders. We point out a number of barriers which impede integrated policy development at the local level: the importance given to local health policy, the medical approach to health development, the organizational self-interest rather than public health concern, the absence of policy entrepreneurial activity.

Furthermore, this article advocates the use of complementary theoretical frameworks and the expansion of the methodological toolbox for health promotion. The value of stakeholder and network analysis in the health promotion domain, at this stage, is two-fold. First, mapping relevant actors, their positions and connections in networks provides us with insight into their capacity to participate and contribute to health policy development. Second, these new tools contribute to a further understanding of policy entrepreneurial roles to be taken up by health promotion professionals and health authorities in favour of the socio-environmental approach to health.

Notwithstanding the value of this first step, more research is required into both the practical application as well as in the theoretical connections with, for example, Multiple Streams theory.

Why invest in a national public health program for stroke? An example using Australian data to estimate the potential benefits and cost implications

Objectives: Stroke is the world’s second leading cause of death in people aged over 60 years. Approximately 50,000 strokes occur annually in Australia with numbers predicted to increase by about one third over 10-years. Our objectives were to assess the economic implications of a public health program for stroke by: (1) predicting what potential health-gains and cost-offsets could be achieved; and (2) determining the net level of annual investment that would offer value-for-money.

Methods: Lifetime costs and outcomes were calculated for additional cases that would benefit if ‘current practice’ was feasibly improved, estimated for one indicative year using: (i) local epidemiological data, coverage rates and costs; and (ii) pooled effect sizes from systematic reviews.

Interventions: blood pressure lowering; warfarin for atrial fibrillation; increased access to stroke units; intravenous thrombolysis and aspirin for ischemic events; and carotid endarterectomy. Value-for-money threshold: AUD$30,000/DALY recovered.

Results: Improved, prevention and management could prevent about 27,000 (38%) strokes in 2015. In present terms (2004), about 85,000 DALYs and AUD$1.06 billion in lifetime cost-offsets could be recovered. The net level of annual warranted investment was AUD$3.63 billion.

Conclusions: Primary prevention, in particular blood pressure lowering, was most effective. A public health program for stroke
is warranted

Developmental language disorders and adolescent risk: a public-health advocacy role for speech pathologists?

Within the multi-disciplinary team concerned with child and adolescent development, speech pathologists are uniquely positioned to understand the nature and overall developmental significance of language acquisition in childhood and adolescence. Other disciplines contribute valuable insights about psychosocial development during the childhood and adolescent years. The field of developmental psychology, for example provides a large and convincing body of evidence about the role of academic success as a protective factor against a range of psychosocial harms, in particular substance misuse, truancy, early school leaving, and juvenile offending. In this paper, we argue that juvenile offending embodies the notion of "adolescent risk", but in Australia in particular, has been under-investigated with respect to possible associations with developmental language disorders and subsequent academic failure. We present findings pertaining to a sample of 30 male juvenile offenders completing community based orders. Performance on a range of oral language processing and production skills was poorer than that of a demographically similar comparison group. Our results confirm the need to conceptualize language within a broader risk and protective framework. We therefore emphasize the public health importance of early language competence, by virtue of the psychosocial protection it confers on young people with respect to the development of prosocial skills, transition to literacy and overall academic achievement. We argue that speech pathologists are best positioned to advocate at a policy level about the broader public health importance of oral language competence.

Evidence-based public health: what does it offer developing countries?

The global burden of disease and illness is primarily situated in developing countries. As developing countries have limited resources, it is particularly important to invest in public health and health promotion strategies that are effective. Systematic reviews are central to evidence-based public health and health promotion practice and policy. This paper discusses issues surrounding the relevance of evidence-based public health and systematic reviews to the health of developing countries. It argues that there is a lack of systematic reviews relevant to the health priorities of developing countries; many interventions reviewed can not be implemented in resource-poor situations; and, a limited amount of primary research is conducted in developing countries. The paper further argues that improvements in public health are determined not only by effective health services and interventions, but through an approach that includes other sectors and influences broader structural and systematic barriers to health. Given the social complexity of human development, and the inter-sections amongst different development goals, there is no question that gains in developing country public health are unlikely to emerge from systematic reviews alone, but will require decisions about inter-sectoral collaboration and social policy initiatives. Nonetheless, evidence around intervention effectiveness has an important role to play in addressing health priorities in developing countries and resource-poor areas. The public health evidence base urgently needs strengthening, with dedicated effort towards increasing the relevance of primary evidence and systematic reviews.

Criteria for the systematic review of health promotion and public health interventions

Systematic reviews of public health interventions are fraught with challenges. Complexity is inherent; this may be due to multi-component interventions, diverse study populations, multiple outcomes measured, mixed study designs utilized and the effect of context on intervention design, implementation and effectiveness. For policy makers and practitioners to use systematic reviews to implement effective public health programmes, systematic reviews must include this information, which seeks to answer the questions posed by decision makers, including recipients of programmes. This necessitates expanding the traditional evaluation of evidence to incorporate the assessment of theory, integrity of interventions, context and sustainability of the interventions and outcomes. Unfortunately however, the critical information required for judging both the quality of a public health intervention and whether or not an intervention is worthwhile or replicable is missing from most public health intervention studies. When the raw material is not available in primary studies the systematic review process becomes even more challenging. Systematic reviews, which highlight these critical gaps, may act to encourage better reporting in primary studies. This paper provides recommendations to reviewers on the issues to address within a public health systematic review and, indirectly, provides advice to researchers on the reporting requirements of primary studies for the production of high quality systematic reviews.

A glossary for evidence based public health

This glossary seeks to define and explain some of the main concepts underpinning evidence based public health. It draws on the published literature, experience gained over several years analysis of the topic, and discussions with public health colleagues, including researchers, practitioners, policy makers, and students.

Public health nutrition : from principles to practice

A systematic, research-based overview of the central principles and practice issues in the growing field of public health nutrition. With chapters by leading international experts, this is essential reading for practitioners and students in public health, nutrition, health policy and related fields.

Multi-sectoral health promotion and public health : the role of evidence

Background Evidence-informed health promotion and public health is an emerging and ever-changing theme in research and practice. A collaborative approach to gathering and applying evidence is crucial to implementing effective multi-sectoral health promotion and public health interventions for improved population outcomes. This paper presents an argument for the development of multi-sector evidence and discusses both facilitators and challenges to this process.

Methods Sector-specific contacts familiar with decision-making processes were selected from referrals gained through academic, government and non-government networks and interviewed (in-person or via telephone) as part of a small scale study to scope the use of evidence within non-health sectors where decisions are likely to impact on public health.

Results The views gathered are preliminary, and this analysis would benefit from more extensive consultation. Nonetheless, information gathered from the interviews and literature search provide valuable insights into evidence-related decision-making paradigms which demonstrate similarities with, and differences from, those found in the health sector.

Conclusions Decisions in health promotion and public may benefit from consideration of the ways in which disciplines and sectors can work together to inform policy and practice.

Knowledge synthesis, translation and exchange in public health and health promotion: the role of a Cochrane review group

The Cochrane Collaboration is an international non-profit organisation that aims to produce high quality systematic reviews of the effectiveness of health interventions. This work is conducted by 51 Review Groups that span a  range of topics (e.g. pregnancy and childbirth, HIV/AIDS). The role of Fields within the Collaboration has been to actively engage relevant stakeholders internationally to improve the quality and relevance of reviews. Since the inception in 1996 of the Cochrane Public Health and Health Promotion Field, the Cochrane Collaboration has begun to embrace reviews related to public health and health promotion and is adapting to the changing needs of end-users. The introduction of a Cochrane health promotion and public health review group will help ensure that reviews will be oriented towards building evidence for equity and reducing inequalities and best meet the needs of decision-makers, practitioners and consumers. Our role as a Field has led to us working with a range of partners including reviewers,  researchers, practitioners and consumers. Knowledge synthesis, translation and exchange (KST&E) has emerged as an issue in need of further  exploration for practice to influence decision-makers and for policy to  influence practitioners. 2007 will be an exciting year for evidence-informed Health Promotion and Public Health (HPPH) both within the Cochrane Collaboration and for our partners in policy, practice and research.

"Tell us something new!" : the response of planning and transport professionals to public health guidance on the built environment and physical activity

A large proportion of non-communicable disease can be attributed to modifiable risk factors such as poor nutrition and physical inactivity. We present data on planning and transport practitioners' perceptions and responses to government public health guidance aimed at modifying environmental factors to promote physical activity. This study was informed by questions on the role of evidence-based guidance, the views of professionals towards the guidance, the links between guidance and existing legislation and policy and the practicality of guidelines. A key informant 'snowball' sampling technique was used to recruit participants from the main professional planning organisations across England. Seventy-six people were interviewed in eight focus groups. We found that evidence-based public health guidance is a new voice in urban and town planning, although much of the advice is already reflected by the 'accepted wisdom' of these professions. Evidence-based health guidance could be a powerful driver affecting planning practice, but other legislated planning guidance may take priority for planning and transport professionals.

Discursive recontextualization in a public health setting

The authors discuss discursive recontextualization as a process of discursive change in which stable referents may be recombined. As such, discursive recontextualization recognizes the interplay of both stability and instability without necessarily privileging the latter. Drawing on intertextual document analysis of a series of public reports published in the wake of a major health policy initiative in Victoria, Australia— Health to 2050—the authors identify a discursive pattern in which descriptions of a disaggregation from large Health Care Networks to smaller Metropolitan Health Services echo those of an earlier aggregation of individual hospitals into the Health Care Networks. The authors suggest that future research into discourse and organizational change will benefit from greater attention to stabilization and such recontextualization as well as to fluidity and instability. They examine implications for change agents and for researchers in the field.

Introduction : consumer groups and the democratization of health policy

This book examines the important role of consumer activism within health policy in different national contexts. In an age of shifting boundaries between state and civil society, consumer groups are potentially drivers of democratization in the health domain. The expert contributors explore how their activities bring new dynamics to relations between service providers, the medical profession, government agencies, and other policy actors. This book is unique in comprehensively analysing the opportunities and dilemmas of this type of activism, including ambiguous partnerships between consumer groups and stakeholders such as the pharmaceutical industry. These themes are explored within an internationally comparative framework, with case studies from various countries. Students and researchers in the fields of health policy and sociology, public policy and social movements will find this relevant and path-breaking book enlightening. It will also prove invaluable for participants and activists in patient and health consumer organizations.