Never mind the qualitative feel the depth! The evolving role of qualitative research in Cochrane intervention reviews

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1 Original Paper Never mind the qualitative feel the depth! The evolving role of qualitative research in Cochrane intervention reviews Journal of Research in Nursing 1 10! The Author(s) 2010 Reprints and permissions: sagepub.co.uk/journalspermissions.nav DOI: / jrn.sagepub.com Jane Noyes Cochrane Qualitative Research Methods Group and Noreen Edwards Chair in Nursing Research, Centre for Health-Related Research, Fron Heulog, Bangor University, Bangor, UK Abstract Whilst the Cochrane intervention review remains the gold standard, the previous focus on randomised controlled trials and exclusion of other types of evidence limited their utility for some users especially policy makers and commissioners of services who had to draw on other types of evidence about patient views and context in order to make decisions. This paper reports a significant development in the evolution of the Cochrane intervention review and outlines an evolving role for qualitative evidence. Policy and methodological developments within the Cochrane Collaboration and beyond will be discussed alongside an ongoing debate about the politics of evidence and perceived power of the quantitative effectiveness review in an evidence-based practice context. The paper concludes with six key messages, including: (1) the Cochrane Collaboration has consistently acknowledged the potential value of qualitative evidence; (2) Cochrane was an early leader in quantitative evidence synthesis and developed a gold standard approach for effectiveness reviews; (3) early leaders in the field tend to dominate until other approaches are developed, tested and evaluated to challenge early leader dominance; (4) other review organisations and individuals have now developed expertise in qualitative and mixed method synthesis and there is an emerging and developing evidence base with a range of qualitative synthesis approaches for different contexts; (5) there is still a need for further methodological development, testing and evaluation, and (6) finally, more than one hierarchy of evidence is needed to address different types of questions, and the dominance and application of one hierarchy to all contexts is unhelpful and counterintuitive to achieving evidence-based healthcare. Keywords evidence-based healthcare, Cochrane Collaboration, evidence synthesis, systematic review Corresponding author: Jane Noyes, Cochrane Qualitative Research Methods Group and Noreen Edwards Chair in Nursing Research, Centre for Health-Related Research, Fron Heulog, Bangor University, Bangor, LL57 2EF, UK. jane.noyes@bangor.ac.uk

2 2 Journal of Research in Nursing Introduction The Cochrane Collaboration is an international not-for-profit independent organisation (Cochrane Collaboration, 2010a). The Collaboration is dedicated to making information about the effects of healthcare available worldwide, and promotes the search for evidence in the form of clinical trials and other studies of interventions. Whilst other systematic review organisations such as the UK Centre for Reviews and Dissemination (CRD, 2009) and Evidence for Policy and Practice Information Centre (EPPI-Centre, 2010) have developed mixed method approaches to evidence synthesis that address broader public health and social care questions, the Cochrane intervention review is widely considered the gold standard approach for the synthesis of quantitative evidence to determine intervention effectiveness. Over the last two decades Cochrane methods groups have increased in size and their membership have worked to refine and test Cochrane approaches to the synthesis and meta-analysis of quantitative evidence of effects. Alongside a programme of methodological development, the Cochrane intervention Handbook (Higgins and Green, 2008, 2009) has been developed and refined and is used by review groups around the world. With a clear policy in place concerning conflicts of interest for those involved in producing reviews, the Cochrane intervention review has developed a reputation of being unbiased and trustworthy. The Cochrane library contains the largest collection of systematic reviews of interventions and their effects in the world and is widely accessed. The library has become the major source of evidence for policy makers, clinicians and the public. New innovations to engage with users and disseminate evidence and information to a wider audience include podcasts, Cochrane TV, Twitter and the Cochrane journal club. Whilst the Cochrane intervention review remains the gold standard and commands high respect, the focus on randomised controlled trials and exclusion of other types of evidence limits their utility for some users especially policy makers and commissioners of services who have to draw on other types of evidence about patient views and context in order to make decisions. For example, a Cochrane intervention review may provide clear evidence of the effectiveness of an intervention but does not include evidence on how people experience the intervention or how it fits with their lifestyle or matches with their preferred choices or expectations. The latter evidence about views, experiences, lifestyles, concordance, attrition and undesired effects is more likely to be qualitative. In this context, I usually define qualitative research as studies that are informed by a qualitative method of data collection AND analysis. In addition, many aspects of treatment and care cannot be evaluated by randomised trials, especially in sensitive areas such as end of life care. This article reports a significant development in the evolution of the Cochrane intervention review and outlines an evolving role for qualitative evidence. Policy and methodological developments within the Cochrane Collaboration will be discussed alongside an ongoing debate about the politics of evidence and the perceived power of the quantitative effectiveness review in an evidence-based practice context. Birth of the Cochrane Qualitative Research Methods Group Before leaving the Collaboration to take up his position as Editor of the James Lind Library, its founder Sir Iain Chalmers encouraged and supported the setting up of the Cochrane Qualitative Research Methods Group. The remit of the group is to advise the Collaboration

3 Noyes 3 and develop methods for the integration of qualitative evidence with Cochrane intervention reviews. Since inception of the Cochrane Qualitative Research Methods Group a decade ago, the value of qualitative evidence has been acknowledged. The dialogue has been about whether the methods for the appraisal, synthesis and integration of qualitative evidence are sufficiently developed and evaluated to be able to add value and improve the utility of selected Cochrane intervention reviews, whether the Collaboration has sufficient expertise and resources to diversify and evolve the Cochrane gold standard intervention effectiveness review approach, or whether mixed method evidence synthesis should be left to other organisations and groups with appropriate existing expertise and resources. Central to this dialogue has been the issue that methods for the synthesis of qualitative evidence have been subject to ongoing development, there had been little funded methodological evaluation, and few high quality qualitative syntheses had been published. Over the last decade confidence in methods for the synthesis and integration of qualitative evidence has grown as more high qualitative syntheses have been published in peer reviewed journals, qualitative reviewers have generally gained more experience, and reports of qualitative methodological evaluations have been published. It is beyond the scope of this opinion piece to present a critique of the evolution of qualitative synthesis methods and their current application. See Barnett-Page and Thomas (2009) for a comprehensive overview of a range of methods and their recent evaluation and application. Over time, an increasing level of shared understanding with key people has been achieved that methods for synthesis of quantitative AND qualitative evidence are evolving, with quantitative synthesis methods having a head start and are therefore more developed, tested and understood than qualitative synthesis methods (Tricco et al., 2010). The explosive politics of evidence Whilst the Cochrane Collaboration has been considering these issues, there has been an interesting and vociferous debate played out by academics and journalists concerning the exclusion of other forms of evidence, such as qualitative evidence, from Cochrane intervention reviews. On a similar vein, there has been much disquiet in some academic communities that hierarchies of evidence and approaches to evidence synthesis used by organisations such as Cochrane are exclusionary (Holmes et al., 2006; Murray et al., 2008). Although there are substantial numbers of nurses and midwives in leading roles in the Cochrane Collaboration, who have done much to advance the evidence-base for effective nursing care (for example the Cochrane Wounds Group), and there is a strong nursing presence in the Cochrane Qualitative Research Methods Group, some of the strongest protagonists against the Cochrane approach have come from Nursing. For example, Holmes et al., in their 2006 paper Deconstructing the evidence-based discourse in health sciences: truth, power and fascism asserted that the evidence-based movement in health sciences constitutes a good example of micro fascism at play in a contemporary scientific arena. In the paper, they set out to demonstrate that the evidence-based movement in the health sciences is outrageously exclusionary and dangerously normative with regards to scientific knowledge. In response, the journalist Ben Goldacre ravaged the authors in his online Bad Science column and in the Guardian newspaper (Goldacre, 2006). Goldacre s

4 4 Journal of Research in Nursing text flowed off the webpage page like narrative mud that was flung back in the direction of Holmes et al. Goldacre wrote with characteristic verve: Even from looking at the title, you just know this academic paper, from the September edition of the International Journal of Evidence-based Healthcare, is going to be a corker. And it uses the word fascist (or elaborate derivatives) 28 times in 6 pages, which even Rik Mayall in the Young Ones might have described as overdoing it. The fascist analogy hit at the heart of the Cochrane Collaboration, which was named after Archie Cochrane, who fought in two conflicts against fascism, and whose ten principles of collaboration were founded on collegiality, minimising conflicts of interest and maximising diversity (Cochrane Collaboration, 2010b). Nonetheless, in the same Guardian article Holmes et al. were able to wrong foot Goldacre in spectacular style, when he managed to achieve the equivalent of shooting himself in the foot by claiming on his Bad Science website that Cochrane reviews did indeed include more types of evidence and not just trials (Goldacre, 2006). Whilst aiming to demonstrate how phenomenally ignorant the authors of this dismal social science piece were about evidence based medicine, Goldacre included a link to a published systematic review in the Cochrane Library and hypothesised: I m not going to re-read this Cochrane review right now, but it s perfectly possible, given the question they were examining, that amongst the many other forms of data in there they may not actually have cited a single trial. Unfortunately for Goldacre, at the time Cochrane reviews excluded qualitative evidence and the link took the reader to a systematic review of the effectiveness of vaccines for Measles, Mumps and Rubella that included only trials. Thus the sparring match probably ended in a draw with both sides scoring equal own goals. Other academics such as Porter and O Halloran have offered their analysis and reflection on theoretical and conceptual assumptions underpinning Holmes et al. s thesis on the positioning and organisation of evidence, and its application and synthesis in an evidencebased practice context, which in turn has provided an opportunity for a re-run of the match with no end game in sight (Porter and O Halloran, 2009, 2010; Holmes et al., 2009). Reconciling positions At one level this largely academic debate has had a positive effect by bringing out into the open perceived injustices and weaknesses in the fabric of the holy grail of evidence-based healthcare. At another level, the debate has been an unhelpful companion when trying to build alliances and develop shared understanding about the methodological developments required when considering integrating qualitative evidence with a Cochrane intervention review. To put it simply one unintended impact of this type of personalised debate is that people are turned off and run for cover lest they say anything to reignite the unwelcome fire. At the heart of it, it is unlikely that there is much disagreement about what constitutes a general definition of evidence-based healthcare. Most definitions talk about using evidence in combination with best clinical judgment, and patient views and choices to make decisions. Evidence-based healthcare is therefore complex and involves a number of elements coming together (quality and availability of evidence, informed and competent clinician, patient readiness to process information and contribute views, appropriate local service delivery infrastructure etc).

5 Noyes 5 To this complex dynamic of evidence, expertise, patient and clinical decision making and service delivery, the Cochrane Collaboration currently contributes systematic reviews of intervention effects to be used in combination with other types of evidence when making decisions in real life contexts. Cochrane does what it is good at and has spent the last 20 years developing the approaches for that is, systematic reviews of effects by synthesising and pooling trial outcomes. Hierarchies and grading of evidence Where there appears to be an ongoing lack of consensus concerns the interpretation of perceived quality of evidence, and how evidence is graded in a hierarchical manner. In a Cochrane intervention effectiveness context, a hierarchy of evidence was developed that positioned the randomised controlled trial over and above other types of evidence, including qualitative evidence which lounges in the lower (if not the lowest) league. When determining the effectiveness of interventions, it is probably right to assume that outcomes from a trial are central to determining effectiveness. As a qualitative researcher, I would however argue that other forms of evidence are required to understand how patients (or rather people) experienced the intervention, how it fitted with their lifestyle, whether it would be their intervention of choice and what factors may have affected their concordance with the intervention and therefore its effectiveness? From my own perspective, I would read a Cochrane intervention review if I had a life threatening but curable disease and wanted by far the most effective treatment so I could have the best chance of cure irrespective of whether people experienced the most effective treatment as not too pleasant. On the other hand, if there were two equally effective treatments, I would want to make a choice based on what additional knowledge high quality qualitative evidence could provide. Therefore, the debate for me is not about hierarchies, and mechanisms for grading of evidence for use when determining effectiveness of interventions, it is more about the value of different types of high quality evidence in specific contexts. I do however agree with Holmes et al. that this jigsaw of evidence that contributes to evidence-based healthcare is not consistently brought together in one place for easy access. This job is currently left to mixed method synthesis organisations, guideline developers or individual review groups. Politicians, policy makers, guideline developers, clinicians, and members of the public consistently point out that Cochrane reviews are only part of the story, and on this point I agree with them entirely. I also agree with Holmes et al. that by liberally applying a hierarchy of evidence that has been designed for addressing intervention effectiveness questions to any type of review question or context is unhelpful and misleading. For example, guideline developers seem to consistently apply a traditional hierarchy of evidence for measuring effectiveness to all evidence contained within guidelines rather than signpost the most appropriate evidence to answer specific types of questions, such as what is known about patient preferences. The need for context-specific hierarchies of evidence Risk management speak talks about the right patient, receiving the right intervention, at the right time and for the right reasons. In evidence-based healthcare speak, one could consider using the right hierarchy of evidence (or indeed no hierarchy of evidence), for the right question, and in the right context. A context-specific hierarchy of evidence for views and

6 6 Journal of Research in Nursing experiences of interventions and service delivery contexts could look something like the hierarchy in Figure 1. Although the Grading of Recommendations Assessment, Development and Evaluation (GRADE) Working Group approach includes a traditional hierarchy of evidence to determine effectiveness of interventions, there is an increasing focus on issues of uncertainty and patient views and values when considering strength of recommendations (GRADE Working Group, 2010). There is acceptance that people will have different values and make different decisions. One example from the GRADE website where there is considerable uncertainty about choice of treatment and where only weak recommendations can be made about the risks and benefits of treatment is given in Figure 2. The Hierarchy of evidence for views and experiences of interventions and service delivery contexts outlined in Figure 1 has a clear role in this common type of uncertainty scenario. A synthesis of qualitative or mixed methods evidence could help increase understanding about how patients experience the condition and how and why they make individual decisions about treatment options in specific contexts and to define the uncertainties from the patient perspective. 1. Evidence from at least one systematic review of well designed qualitative studies. 2. Evidence from at least one systematic review of well designed mixedmethod evidence (qualitative, surveys etc) 3. Evidence from at least one well conducted qualitative study, or qualitative process evaluation published in peer review journals. 4. Evidence from well designed research and consumer surveys. 5. Evidence in the form of opinions from lay people, respected authorities, descriptive studies and reports from third sector, public organisations and committees. 6. Evidence from quantitative studies including randomised and nonrandomised and case controlled studies without embedded qualitative or mixed method process evaluation. Figure 1. Hierarchy of evidence for views and experiences of interventions and service delivery contexts Consider a 40 year-old man who has suffered an idiopathic deep venous thrombosis and has been taking adjusted dose warfarin for one year. If the patient continues on standard-intensity warfarin his risk of recurrent DVT will be reduced by approximately 10% per year. The inevitable burdens of the treatment include taking a warfarin pill daily, keeping dietary intake of vitamin K constant, monitoring the intensity of anticoagulation with blood tests, and living with the increased risk of both minor and major bleeding. Some patients who are very averse to a recurrent DVT may consider the down sides of taking warfarin well worth it. Others are likely to consider the benefit not worth the risks and inconvenience. GRADE 2010 Downloaded from: Figure 2. Example: Warfarin for idiopathic deep venous thrombosis (DVT)

7 Noyes 7 Emergence of the multi-method reviewer and new novel approaches to evidence synthesis Along with more novel trial designs, such as those for developing and evaluating complex interventions that incorporate and value qualitative and mixed-method approaches, methods for different types of evidence synthesis have evolved to another level over the past 10 years (MRC, 2000, 2008). Many people with experience of evidence-synthesis are gaining expertise in a range of different approaches, the choice of which may depend on funder requirements and focus, review question, time available and team expertise. In general, Cochrane authors also take into consideration the availability of infrastructure support provided by the organisation, dissemination networks, organisational branding, and added value attributes such as free training, methodological support, availability of software, and impact factor of the associated library. It sometimes seems to be forgotten that the people who conduct Cochrane reviews are mostly unpaid volunteers, many of whom contribute to producing, as well as synthesising, evidence for a range of different funders and organisations. A number of people who contribute to the Cochrane Collaboration and intervention reviews, are also developing, implementing and evaluating novel approaches such as realist synthesis, critical interpretive synthesis and Bayesian synthesis that treat evidence in different ways and where traditional hierarchies of evidence have less or little relevance (see for example Greenhalgh et al., 2007, 2009). Growing numbers of mixed-method health services researchers and social scientists who undertake various types of evidence synthesis and primary research can generally accommodate different types of thinking, different types of evidence and we all struggle with various conceptual, theoretical and methodological issues associated with emerging methodologies and approaches. Like me, academics such as Trish Greenhalge, Mary Dixon-Woods, Nicky Britten and Jo Rycroft-Malone (to name but a few) have a range of interests including intervention reviews, mixed method health services and public health research, implementation science, realist and critical interpretive synthesis and meta ethnography. Every primary and secondary methodological approach has strengths and weaknesses in different contexts and flexibility of thought is required when designing an appropriate protocol for a specific purpose. To demonstrate how quickly methods for novel mixed method research designs and evidence synthesis are evolving and being applied, a quick search of any health or social care related electronic search engine will identify increasing numbers of published examples of evidence syntheses using novel and more integrated approaches to address specific types of questions, with less or no reliance on traditional evidence hierarchies (see for example Greenhalgh et al., 2009; Hoddinnott et al., 2010; Javanparast et al., 2010; Marchal et al., 2010). Publication of new guidance on the role of qualitative research in Cochrane intervention reviews in the new edition of the Cochrane intervention handbook Whilst acknowledging that the Cochrane Collaboration has a number of resource and process issues still to address, the potential value of high quality qualitative evidence has been acknowledged for a number of appropriate Cochrane review questions. For example, qualitative evidence may help understand the complex issues involved when some women

8 8 Journal of Research in Nursing accept higher risks and choose less effective but more woman-centred interventions when making decisions about childbirth interventions. Nonetheless, more methodological work needs to be done on how best to integrate qualitative and quantitative syntheses in a meaningful and robust way within a Cochrane context and using Cochrane software. Colleagues from the Qualitative Research Methods Group have produced guidance on the role of qualitative evidence in a Cochrane intervention review. This guidance was published in Chapter 20 of the new Cochrane handbook (Noyes et al., 2008). The inclusion of qualitative evidence in a limited number of appropriate intervention reviews is a substantial move in position for Cochrane. Colleagues from other Cochrane methods groups have described the experience of moving from the wilderness to the having a Chapter outlining their methodological approach in the Cochrane handbook as moving from the Book of Apothecary to the Holy Grail. I can certainly agree with this! The inclusion of qualitative evidence in a limited number of appropriate intervention reviews is a substantial move in position for Cochrane. In the handbook, we outline that qualitative research can contribute to Cochrane intervention reviews in four ways: (1) Informing reviews by using evidence from qualitative research to help define and refine the question, and to ensure the review includes appropriate studies and addresses important outcomes; (2) Enhancing reviews by synthesising evidence from qualitative research identified whilst looking for evidence of effectiveness; (3) Extending reviews by undertaking a search to specifically seek out evidence from qualitative studies to address questions directly related to the effectiveness review; and (4) Supplementing reviews by synthesising qualitative evidence within a stand-alone, but complementary, qualitative review to address questions on aspects other than effectiveness. At present, the Cochrane Collaboration has the resources to support the first three contributions (informing, enhancing and extending) for a limited number of appropriate reviews, but not stand alone qualitative syntheses (supplementing), which would require a major overhaul of publishing processes and current software. To inform these methodological developments Jenny Popay and I conducted an exemplar synthesis of qualitative evidence to show how a qualitative synthesis could enhance and extend an existing Cochrane review on interventions to promote concordance with directly observed therapy and tuberculosis treatment, published in the Journal of Advanced Nursing (Noyes and Popay, 2007). Trish Greenhalgh and colleagues also published a very timely realist synthesis of evidence from process evaluations conducted alongside RCTs in their Cochrane review of interventions to promote school feeding programmes in developing countries, published in the British Medical Journal (Greenhalgh et al., 2007). Without being phased by hierarchies of evidence Greenhalgh and her colleagues developed a theory as to why some of the poorest children did not benefit as much as other children from receiving food at school. She also made some rather useful comments about the theoretical adequacy of interventions, the benefits of using realist synthesis principles and evidence from trial process evaluations to understand more about what worked and for whom, and called for more innovative ways of designing, implementing and evaluating complex interventions and synthesising evidence.

9 Noyes 9 Co-conveners of the Qualitative Research Methods Group are now producing additional more detailed process-orientated guidance for authors, which will be uploaded as it is produced and agreed on the group website (CQRMG, 2010). We are also working with a small number of Cochrane review authors to walk with them through the process of registering their qualitative part of the protocol, and we are having an ongoing conversation with David Tovey, Editor in Chief of the Cochrane Library, to start considering how best to integrate the products of the quantitative intervention and qualitative evidence syntheses in the Cochrane Library. Conclusion There are six key messages from this long journey. First, it has not generally been all about the potential value (or not) of qualitative evidence. Although I accept that some quantitative minds will always find the philosophical assumptions of qualitative research challenging. Second, the Cochrane Collaboration was an early leader in quantitative evidence synthesis. Over time the Collaboration developed, tested and evaluated a well respected and branded product that became recognised as the gold standard approach to synthesis of evidence on intervention effects. Third, early leaders in the field tend to dominate until other approaches are developed, tested and evaluated to challenge early leader dominance. Fourth, other review organisations and individuals have now developed specific expertise in qualitative and mixed method synthesis and there is an emerging and developing evidence base with a range of qualitative synthesis approaches for different contexts. Whilst methodological consensus remains elusive amongst the qualitative research community, there now appears to be a sufficiently robust evidence base for organisations such as Cochrane to act on findings and work towards improving the value and utility of Cochrane intervention reviews by defining the contribution and value of qualitative evidence in guidance to authors. Fifth, there is still a need for further methodological development, testing and evaluation. In this respect, over time methodological developments will likely follow a similar evolutionary pathway as quantitative synthesis approaches. Methods will be developed, refined, applied and evaluated over time. Finally, and most importantly, is the need for clinicians, review and guideline organisations to take on board that more than one hierarchy of evidence is needed to address different types of questions, and the dominance and application of one hierarchy to all contexts is unhelpful and counterintuitive to achieving evidence-based healthcare. On this issue Holmes et al. and I definitely agree! References Barnett-Page E and Thomas J (2009) Methods for the synthesis of qualitative research: A critical review. BMC Medical Research Methodology 11(9): 59. Centre for Reviews and Dissemination (CRD) (2009) Systematic Reviews: CRD s Guidance for Undertaking Reviews in Health Care. University of York: CRD. Available at: Cochrane Collaboration (2010a) Cochrane Collaboration (2010b) Cochrane Collaboration Ten Principles. Available at: tenprinciples.htm. Cochrane Qualitative Research Methods Group (CQRMG) (2010) Evidence for Policy and Practice Information and Co-ordinating Centre (EPPI-Centre) (2010) eppi.ioe.ac.uk/cms/ GRADE Working Group (2010) Goldacre B (2006) Archie Cochrane: Fascist, Available at: Greenhalgh T, Humphrey C, Hughes J, Macfarlane F, Butler C and Pawson R (2009) How do you modernize a health

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