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This work is funded by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care (CLAHRC) West Midlands. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care.
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Welcome to the latest issue of your CLAHRC West Midlands News Blog where we look at how multiple analyses of one dataset can result in materially different parameter estimates. We also have a guest blog on optimising community health worker programmes. Finally we look at recent papers on mortality rate convergence between countries; the use of standardised patients to examine quality of TB care; a multiple indication review comparing oxygen therapies; and the impact childcare can have on children.

As usual, we also have details of the latest news and events; this issue's quiz question; and highlight some of our latest publications.

We hope that you find these posts of interest, and we welcome any comments. You can find previous issues of our News Blog here.
 Director's Blog

The Same Data Set Analysed in Different Ways
Yields Materially Different Parameter Estimates:
The Most Important Paper I Have Read This Year

News blog readers know that I have a healthy scepticism about the validity of econometric/regression models. In particular, the importance of being aware of the distinction between confounding and mediating variables, the latter being variables that lie on the causal chain between explanatory and outcome variables. I therefore thank Dr Yen-Fu Chen for drawing my attention to an article by Silberzahn and colleagues.[1] They conducted a most elegant study in which 26 statistical teams analysed the same data set.

The data set concerns the game of soccer and the hypothesis that a player’s skin tone will influence propensity for a referee to issue a red card, which is some kind of reprimand to the player. The provenance of this hypothesis lies in shed loads of studies on preference for lighter skin colour across the globe and subconscious bias towards people of lighter skin colour. Based on access to various data sets that included colour photographs of players, each player’s skin colour was graded into four zones of darkness by independent observers with, as it turned out, high reliability (agreement between observers over and above that expected by chance).

The effect of skin colour tone and player censure by means of the red card was estimated by regression methods. The team was free to select its preferred method. The team could also select which of 16 available variables to include in the model.

The results across the 26 teams varied widely but were positive (in the hypothesised direction) in all but one case. The ORs varied from 0.89 to 2.93 with a median estimate of 1.31. Overall, twenty teams found a significant (in each case positive) relationship. This wide variability in effect estimates was all the more remarkable given that the teams peer-reviewed  each other’s methods prior to analysis of the results.

All but one team took account of the clustering of players in referees and the outlier was also the single team not to have a point estimate in the positive (hypothesised) direction. I guess this could be called a flaw in the methodology, but the remaining methodological differences between teams could not easily be classified as errors that would earn a low score in a statistics examination. Analytic techniques varied very widely, covering linear regression, logistic regression, Poisson regression, Bayesian methods, and so on, with some teams using more than one method. Regarding covariates, all teams included number of games played under a given referee and 69% included player’s position on the field. More than half of the teams used a unique combination of variables. Use of interaction terms does not seem to have been studied.

There was little systematic difference across teams by the academic rank of the teams. There was no effect of prior beliefs about what the study would show and the magnitude of effect estimated by the teams. This may make the results all the more remarkable, since there would have been no apparent incentive to exploit options in the analysis to produce a positive result.

What do I make of all this? First, it would seem to be good practice to use different methods to analyse a given data set, as CLAHRC West Midlands has done in recent studies,[2] [3] though this opens opportunities to selectively report methods that produce results convivial to the analyst. Second, statistical confidence limits in observational studies are far too narrow and this should be taken into account in the presentation and use of results. Third, data should be made publically available so that other teams can reanalyse them whenever possible. Fourth, and a point surprisingly not discussed by the authors, the analysis should be tailored to a specific scientific causal model ex ante not ex post. That is to say, there should be a scientific rationale for choice of potential confounders and explication of variables to be explored as potential mediating variables (i.e. variables that might be on the causal pathway)
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-- Richard Lilford, CLAHRC WM Director

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References

CLAHRC WM Quiz
 
Other than snakes, which animal is commonly used in the production of snake antivenom?

Email CLAHRC WM your answer.
Answer to our previous quiz: The portrait was of Sheikh Mujibur Rahman, who was founding father of the People's Republic of Bangladesh. Please click here for more information.

Congratulations to Ewan Harrison and Magdalena Skrybant who was first to answer correctly. 
 Guest Blog

Evidence-Based Guidelines and Practitioner Expertise
to Optimise Community Health Worker Programmes

The rapid increase in scale and scope of community health worker (CHW) programmes highlights a clear need for guidance to help programme providers optimise programme design. A new World Health Organization (WHO) guideline in this area [1] is therefore particularly welcome, and provides a complement to existing guidance based on practitioner expertise.[2] The authors of the WHO guideline undertook an overview of existing reviews (N=122 reviews with over 4,000 references included), 15 separate systematic reviews of primary studies (N=137 studies included), and a stakeholder perception survey (N=96 responses). The practitioner expertise report was developed following a consensus meeting of six CHW programme implementers, a review of over 100 programme documents, a comparison of the standard operating procedures of each implementer to identify areas of alignment and variation, and interviews with each implementer.

The volume of existing research, in terms of the number of eligible studies included in each of the 15 systematic reviews, varied widely, from no studies for the review question “Should practising CHWs work in a multi-cadre team versus in a single-cadre CHW system?” to 43 studies for the review question “Are community engagement strategies effective in improving CHW programme performance and utilization?”. Across the 15 review questions, only two could be answered with “moderate” certainty of evidence (the remainder were “low” or “very low”): “What competencies should be included in the curriculum?” and “Are community engagement strategies effective?”. Only three review questions had a “strong” recommendation (as opposed to “conditional”): those based on Remuneration (do so financially), Contracting agreements (give CHWs a written agreement), and Community engagement (adopt various strategies). There was also a “strong” recommendation not to use marital status as a selection criterion.

The practitioner expertise report provided recommendations in eight key areas and included a series of appendices with examples of selection tools, supervision tools and performance management tools. Across the 18 design elements, there was alignment across the six implementers for 14, variation for two (Accreditation – although it is recommended that all CHW programmes include accreditation - and CHW:Population ratio), and general alignment but one or more outliers for two (Career advancement – although supported by all implementers, and Supply chain management practices).

There was general agreement between the two documents in terms of the design elements that should be considered for CHW programmes (Table 1), although not including an element does not necessarily mean that the report authors do not think it is important. In terms of the specific content of the recommendations, the practitioner expertise document was generally more specific; for example, on the frequency of supervision the WHO recommend “regular support” and practitioners “at least once per month”. The practitioner expertise report also included detail on selection processes, as well as selection criteria: not just what to select for, but how to put this into practice in the field. Both reports rightly highlight the need for programme implementers to consider all of the recommendations within their own local contexts; one size will not fit all. Both also highlight the need for more high quality research. We recently found no evidence of the predictive validity of the selection tools used by Living Goods to select their CHWs,[3] although these tools are included as exemplars in the practitioner expertise report. Given the lack of high quality evidence available to the WHO report authors, (suitably qualified) practitioner expertise is vital in the short term, and this should now be used in conjunction with the WHO report findings to agree priorities for future research.
 
Table 1: Comparison of design elements included in the WHO guideline and Practitioner Expertise report

-- Celia Taylor, Associate Professor.

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References

 Director's Choice - From the Journals

Mortality Rate Convergence between High- and Low-Income Countries

A recent Lancet commission led by Watkins and others examined the rate of convergence between high- and low-income countries for a number of conditions.[1] Huge progress has been made in mortality of under-fives and from HIV/AIDS. Progress is less impressive for maternal mortality, and less impressive still for tuberculosis mortality. The authors argued for greater investment in the latter two topics. Other topics singled out for good reason include cervical cancer, hepatitis B and rheumatic heart disease, all on the grounds of great disparities between rich and poor populations. They also argue that more attention must be paid to preparing for pandemics, a topic covered by CLAHRC West Midlands.[2]

The authors argue for greater domestic spending and point out that the economic returns on investment arise from both increased productivity and the improvement in human welfare, such as that captured in DALYs. But they are very keen to see better targeting of expenditure, which will require careful economic analysis, such as that we are carrying out into ambulance services. The authors argue for more savvy procurement to shape markets using Gavi, the vaccine alliance, as an excellent example. Following this model, rich countries could incentivise industry to develop new treatments for tuberculosis, for example. The authors make the excellent point that huge improvements could come from closing the delivery practice gap through population, policy and implementation research. The spread of unhealthy products needs to be curtailed following the model of the WHO convention in tobacco control.

A recurring theme is that many of the above objectives require international action: shaping markets, preparing for pandemics, and preventing diffusion if unhealthy products, for example. I am writing this report from Kigali at the close of the NIHR Global Surgery Unit conference. This has been precisely the kind of international collaboration that the authors are arguing for.

.
-- Richard Lilford, CLAHRC WM Director

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References
 

Examining Quality of TB Care with Standardised Patients

Kwan and colleagues have recently published another study to add to their growing portfolio of research on the use of standardised patients (SP) (i.e., actors trained to act as a real patient and portray a case) to examine the quality of tuberculosis (TB) care in India.[1] This interesting paper builds on their prior work, some of which we have discussed in earlier editions of this blog.[2]

TB is a significant problem in India. It accounts for a quarter of the world’s estimated 10.4 million new cases of TB annually, and nearly a third of the 1.7 million yearly TB deaths. The quality of healthcare provision in India’s private sector – the first point of contact for the bulk of symptomatic TB patients – is generally accepted to be suboptimal and highly variable.

This impressive study involved 2,652 SP-provider interactions across 1,203 health facilities and 1,288 provider practices in two economically disparate Indian cities (Mumbai and Patna) with a high prevalence of cases of TB. It focused on healthcare providers both with and without formal medical training, and was covertly nested within a Government of India initiated TB management improvement programme. The authors trained 24 local actors (seven female and 17 male) to portray four scenarios representing various stages of diagnostic and disease progression of TB. Over a nine month period, SPs undertook incognito visits to providers – with measures in place to protect against detection. Within two-hours of each visit a field researcher administered exit questionnaires to SPs to record details of the interaction. The main outcome of interest in this study was case-specific correct management based on local clinical guidelines for the management of TB.

The key findings were that: 

  • Only 25% of SP-provider interactions resulted in standards-compliant care.
  • Only 35% of cases were correctly managed and of these, 53% of providers ordered a chest X-ray, 36% referred the SP for further care (roughly equal split of referrals to private and public sector providers), and 31% ordered a microbiological test for diagnosis – a relatively infrequent occurrence across all case scenarios.
  • Medicines (mostly antibiotics) were very frequently prescribed or dispensed – the average rate was three per interaction.
  • Rather unsurprisingly, yet reassuringly, medically trained providers were almost three times more likely than non-medically trained providers to correctly manage cases, ask for chest X-ray and/or sputum tests, and initiate anti-TB treatment.
  • Differences in case management for medically and non-medically trained providers between Mumbai and Patna were minimal.
However, the important take-home message is that, in spite of providing relatively higher-quality care, medically trained providers still only correctly managed 54% of interactions, and were more likely than others to prescribe unnecessary or harmful antibiotics, which in a global epidemic of antibiotic resistance, is a particularly worrying result.

A key strength of this study is that it provided representative data on actual provider behaviour, thus addressing the widely acknowledged ‘know-do’ gap, though it also reiterates two important and recurrent considerations for the use of SPs in research studies:
  1. SPs are most useful for first-visits and have not yet been used in repeat visits. But is it reasonable to assume that quality of care may be better at a follow-up visit? This is an issue worthy of investigation in future work.
  2. Should we be asking for prior consent from participating providers? A continuing issue of contention, particularly relevant to the use of SPs in real-life (not educational) settings.

-- Navneet Aujla, Research Fellow.

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References
 

Multiple Indication Review:
Liberal vs Conservative Oxygen Therapy in Acutely Ill Patients

Readers of the News Blog may know that we advocate the examination of evidence in its totality beyond the silos of individual diagnoses and conditions – if the underlying mechanism of a phenomenon or the hypothesis to be tested is common across these conditions. This can be achieved by a multiple indication review, a systematic review that examines the effects of an intervention or variable across different conditions.[1] Earlier this year Chu and colleagues published an excellent example of a multiple indication review, in which they examined evidence from randomised controlled trials (RCTs) that have compared liberal versus conservative use of oxygen in adults with acute illness.[2] They identified 25 RCTs including a total of 16,037 patients across neurological conditions (stroke and traumatic brain injury), sepsis, emergency surgery, critical care and cardiac conditions (myocardial infarction and cardiac arrest). A meta-analysis of this evidence across all conditions showed that liberal use of oxygen increased the risk of in-hospital death by 21% (relative risk 1.21, 95% CI 1.03 to 1.41) compared with a more conservative use. A similar, although slightly smaller increase in risk was also found for 30-day mortality and mortality at the longest follow-up of individual trials.

The findings were homogeneous within and across different conditions, and were supported by a meta-regression showing positive correlation between relative risk of in-hospital mortality and percentage point increase in SpO2 (peripheral oxygen saturation). Liberal use of oxygen did not offer any benefits for reducing disability for patients suffering from stroke and traumatic brain injuries, nor did it reduce hospital length of stay and hospital-acquired infections for acute medical admissions. The only notable difference is that a liberal strategy of oxygen therapy was associated with reduced hospital-acquired infections for acute surgical admissions (RR 0.50, 95% CI 0.36 to 0.69). This finding was based on data from two RCTs that were terminated early and the authors urged further investigation in this patient population. Taken together, it appears too much of oxygen is not good for acutely ill patients. This conclusion, while contradicting some conventional wisdom, is also supported by several plausible mechanisms through which very high level of oxygen could damage our body such as causing acute lung injury and triggering inflammatory responses.[3]Establishing the optimum range of oxygen saturation that minimises the competing risks of hypoxaemia and hyperoxaemia”, as the authors suggested, seems to be the way forward.

-- Yen-Fu Chen, Principle Research Fellow.

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References

Impact of Childcare on Children

Leaving your child crying at the nursery door is a difficult experience that can leave a working parent questioning whether they have the right priorities. When I first experienced this a few years ago, a good friend working at Cancer Research sent me a summary of research showing an inverse association between institutional childcare and childhood cancer (probably mediated by early childhood infections). “Don’t worry, going to nursery is doing at least some good for your child!” she said.

A new study using data from the EDEN mother-child cohort (based in France) gives additional reasons to alleviate working parent guilt.[1] This study examined childcare arrangements in the first three years of life for 1,428 children, categorising this as: with a childminder, centre-based (i.e. nursery or crèche staffed with professionals), or informal (primarily parents, complemented with grandparents or other non-professionals). Emotional and behavioural development of the child were assessed at age 3, 5.5 and 8 years. Confounders, including child factors (such as birthweight, duration of breastfeeding), parental sociodemographic factors (such as marital status, mother’s perception of partner support), and parents’ mental health, were considered in analyses through propensity scores and inverse probability weights.

Formal childcare was found to predict lower levels of emotional symptoms and peer-relationship problems, and promote high levels of prosocial behaviour even at age 8. Children who were in centre-based childcare had the lowest levels of emotional symptoms and peer relationship problems.

Surprisingly (to me), subgroup analyses showed that girls, children whose mother had high education, and those whose mother was not depressed may benefit the most from formal childcare. The authors state that the result for girls is likely to be because childcare mainly reduces internalising problems which are more prevalent in girls. The fact that the other ‘low-risk’ children fare better when exposed to formal childcare is suggested to be because the universal curriculum is most appropriate for those who do not have more severe emotional and social development issues.

Clearly there are many things to consider when deciding whether to work while also a parent to a small child, even if a rule generally applies, only the person making the decision knows the context of their own family and what suits them best. Also worth noting that this observational study cannot prove a causal relationship. But for those of us who do choose to leave a child in centre-based care- this paper offers some solace in those moments of ambivalence.

-- Oyinlola Oyebode, Associate Professor

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Reference

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News & Events

Video Showcasing Links Between WBS and Healthcare

The Chartered Association of Business Schools have recently published a video showcasing the work of UK business schools. It includes a piece from Warwick Business School in their links with the healthcare industry, and features contributions from Graeme Currie (CLAHRC WM Deputy Director), Andy Hardy (CEO for University Hospitals Coventry & Warwickshire), and Magdalena Skrybant (CLAHRC WM PPIE Officer). It can be viewed online at: https://charteredabs.org/the-impact-factor/ (select Part 1 05 from the playlist on the right).


Call for Abstracts

The call for abstracts for the 2019 HSRUK Conference recently opened, and they are accepting submissions on all aspects of health services, systems and policy research. Please click here for more information, and to submit. The deadline is midnight on Sunday 13 January 2019. The conference itself will be held on 2-3 July 2019 at the University of Manchester.


Warwick Christmas Lecture

Dr Celia Taylor (who works with CLAHRC WM theme 6, Research Methods) is presenting at this year's Warwick Christmas Lectures on Monday 26 November. Her lecture will look at how we can describe risk and use this knowledge to help make decisions in the context of deciding whether to take a medicine given the risk of side-effects. It will also look at how well (or not) evidence is presented in journal articles. 

More information, including how to book, is available online..


NIHR Funding Opportunities

The latest funding opportunities from the NIHR are now available:

18/167 End of life care (EME programme)
18/168 Precision medicine (EME programme)

18/173 Digital technologies to improve health and care

18/174 End of life care (HS&DR programme)
18/175 Precision medicine (HS&DR programme)

18/176 End of life care (HTA programme)
18/177 Precision medicine (HTA programme)

18/179 End of life care (PHR programme)

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Recent Publications

Camacho EM, Davies LM, Hann M, Small N, Bower P, Chew-Graham C, Baguely C, Gask L, Dickens CM, Lovell K, Waheed W, Gibbons CJ, Coventry P. Long-term clinical and cost-effectiveness of collaborative care (versus usual care) for people with mental-physical multimorbidity: cluster-randomised trial. Br J Psychiatry. 2018; 213(2): 456-63.

Helliwell T, Muller S, Hider SL, Zwierska I, Lawton S, Richardson J, Mallen C. Challenges of diagnosing and managing polymyalgia rheumatica: a multi-methods study in UK general practice. Br J Gen Pract. 2018; 68: e783-93.

Hemming K, Taljaard M, McKenzie JE, Hooper R, Copas A, Thompson JA, Dixon-Woods M, Aldcroft A, Doussau A, Grayling M, Kristunas C, Goldstein CE, Campbell MK, Girling A, Eldridge S, Campbell MJ, Lilford RJ, Weijer C, Forbes AB, Grimshaw JM. Reporting of stepped wedge cluster randomised trials: extension of the CONSORT 2010 statement with explanation and elaboration. BMJ. 2018; 363: k1614.

O'Connell Francischetto E, Damery S, Ferguson J, Combes G, on behalf of the myVideoClinic randomised evaluation steering group. Video clinics versus standard face-to-face appointments for liver transplant patients in routine hospital outpatient care: study protocol for a pragmatic randomised evaluation of myVideoClinic. Trials. 2018; 19: 574.

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