ESMI's paper pick

This month the honour goes to Simon Briscoe for his commentary “The loss of the NHS EED and DARE databases and the effect on evidence synthesis and evaluation” in Research Synthesis Methods.

We asked Simon to give us some background and context to the paper:

“In January 2015 the National Institute for Health Research announced that funding for the NHS Economic Evaluation Database (NHS EED) and the Database of Abstracts of Reviews of Effects (DARE) would be discontinued in March 2015. In the two years since then, the loss of these databases has been keenly felt in the information specialist and wider research community. NHS EED and DARE were both excellent resources for scoping searches of economic evaluations and systematic reviews respectively, enabling the searcher to quickly identify relevant studies more efficiently than in larger databases. They also included critical appraisal of studies and indexed some grey literature items not indexed in larger databases.

In July 2015 InterTASC – the community of health technology assessment agencies who support health policy decision making by NICE – asked the InterTASC information specialist sub-group (ISSG) to review the effect that the loss of NHS EED and DARE would have on their work. ISSG produced a report which stated that identifying and appraising economic evaluations and systematic reviews would now require more time and resources, and that this would be particularly significant in scenarios such as scoping, where the aim is to conduct a rapid assessment of the literature.

In addition to reporting to InterTASC, I had the idea that ISSG could write a letter on this issue to a prominent journal. Although the loss of NHS EED and DARE was keenly felt, there did not appear to be anything formally published which expressed this view or the more general point that smaller databases add value to research and yet often have less secure funding than larger databases. Although ISSG voted against my idea (mainly because a long time had elapsed since the discontinuation of funding when we voted in 2016 – admittedly true!) several ISSG members expressed interest. I, Chris Cooper, Julie Glanville (YHEC) and Carol Lefebvre (independent information consultant and co-convener of the Cochrane Information Retrieval Methods Group) worked on a draft independently of ISSG, which Research Synthesis Methods invited us to submit as a commentary. The early view version was published in March this year.

We hope that our commentary will highlight the value of smaller databases and encourage more efforts to protect their funding. We suggest in our commentary that one way to do this would be improved communication links between databases users, funders and producers”.

Congratulations to Simon and colleagues for their work to promote the importance of maintaining funding to protect vital data sources.

This month the honour goes to Alison Bethel and colleagues from the UEMS European Centre for Environment and Human Health School for their mixed methods systematic review paper “A systematic review of the health and well-being impacts of school gardening: synthesis of quantitative and qualitative evidence” in BMC Public Health.

We asked Alison to give us some background and context to the paper, which was led by Dr Becca Lovell:

“School gardening and food growing have become popular activities in thousands of schools around the world. National school gardening programmes exist in some countries the individuals and organisations behind these programmes believe that school gardening has the potential to improve children’s health, social development and academic attainment. Several studies had been published on the impact and meaning of school gardening programmes, so we felt it was justified and timely to conduct a robust, mixed methods systematic review of the health and well-being impacts of school gardening, to support and inform the further development of this popular school-based intervention.” 

The authors included 40 studies (21 quantitative, 3 mixed methods and 16 qualitative) in the review. Despite limited quantitative evidence of benefit, Alison highlighted that the qualitative studies mostly reported positive health and educational benefits, as depicted by some of the following quotes:

“It makes me feel good inside, all fresh, good… I enjoy touching the soil, the plants. You can feel them…I feel part of them…Yes, it makes me feel that I can care more about things… Being more gentle, caring more, the plants are like people” (student aged 17)

“When I grow them [vegetables] I feel like I should always try it. And when I’ve grown them I like them better than the shop ones” (child, primary school)

“You’ll have to read the paper if you want to find out what we concluded overall” says Alison!

Congratulations to Alison and colleagues for their work to inform the further development of school gardening programmes.

This month the honour goes to Daniel Chalk for his publication “Which factors most influence demand for ambulances in South West England?” in Journal of Paramedic Practice. 

We asked Daniel to give us some background and context to his paper:

"We were approached by the South West Ambulance Service NHS Foundation Trust (SWAST) to see if modelling could help to gain a better understanding of local demand for ambulance services.  Although within-year fluctuations in demand are well understood, nationally there has been an increasing year-on-year demand for ambulance services for some time, with little to no understanding of the key drivers of this demand.

We developed a System Dynamics simulation model – typically used to model large-scale or abstracted systems – in order to model a multitude of factors that may directly or indirectly influence the demand for ambulance services.  These influencing factors were identified using a combination of literature review and expert opinion from SWAST.  By modelling the complex interplay amongst these factors, we could start to unpick things and one-by-one remove each influencing factor to observe the impact on predicted volumes of ambulance calls.  We could then identify the factors whose removal led to the biggest predicted reductions in ambulance demand as being more influential determinants of demand for ambulance services.

We did this, and we found that by far and away the most influential driver of demand for ambulance services in the South West is the prevalence of falls amongst older people.  We found that this factor was estimated to be over three times more influential than other known sources of high demand for ambulances, such as the 111 service.  We also found that the increased propensity of those with mental health needs to use ambulance services was estimated to be a significant contributor to overall demand.

We presented these results to SWAST executives, who said that they had long suspected these factors to be significant drivers of demand for their services, but they lacked the evidence to demonstrate this.  As a result, we were asked to present our findings to the lead commissioners for South West England who, on the back of our evidence, asked for falls prevention strategies to become priority issues with local commissioners across the South West.  We hope that, in time, such efforts will lead to tangible reductions in the growth of demand for ambulance services in the South West".

Congratulations to Daniel and colleagues in ESMI for their current and ongoing work to help inform the emergency services.

This month the honour goes to Jaime Peters for her publication "Can clinical features be used to differentiate type 1 from type 2 diabetes? A systematic review of the literature" in BMJ Open. 

We asked Jaime to give us some background and context to her paper:

"This work came about through discussions with clinical experts on the difficulty of classifying individuals as having type 1 or type 2 diabetes. Evidence suggests that 7-15% of individuals with diabetes are misclassified, and so receive inappropriate treatment. In the absence of evidence-based guidance on what clinical features can help classification, type 1 diabetes has been considered the likely diagnosis for young, slim individuals, whereas type 2 diabetes is more likely in older people who are obese. However, with increases in the prevalence of obesity leading to more cases of type 2 diabetes being seen in younger individuals, classification of type 1 and type 2 diabetes is becoming even less certain.

To address this problem Dr Bev Shields lead a successful proposal to the NIHR Research for Patient Benefit funding panel which included a systematic review of the literature to evaluate the performance of clinical features, such as age and BMI, to differentiate individuals with type 1 from type 2 diabetes.

After reviewing almost 11,000 titles and abstracts, we found just 11 studies that were eligible for our systematic review. There were considerable differences across the studies, however age at diagnosis of diabetes and time to insulin treatment after diagnosis were consistently the better performing clinical features reported in the studies. As for BMI, although used in clinical practice, it was not found to be useful when added to age at diagnosis and time to insulin treatment to distinguish type 1 from type 2 diabetes. These clinical features are similar to the Royal College of General Practitioners (RCGP) NHS Diabetes classification guidelines for classifying type 1 diabetes which are based on consensus expert opinion (age at diagnosis <35 years and received insulin treatment within 6 months of diagnosis). We therefore concluded that the RCGP guidelines should be used until further good-quality studies, preferably looking at individuals close to diagnosis, are carried out.

We are now conducting a systematic review to evaluate whether autoantibody testing close to diagnosis can help to differentiate individuals with type 1 from type 2 diabetes. View the protocol.

Congratulations to Jaime and colleagues in ESMI for their current and ongoing work to classify individuals with type 1 or type 2 diabetes.

This month the honour goes to Tristan Snowsill for his publication "A model-based assessment of the cost–utility of strategies to identify Lynch syndrome in early-onset colorectal cancer patients" in BMC Cancer. 

We asked Tristan to give us some background and context to his paper:

"This was my first major project as a part of ESMI and it involved very close working with colleagues in ESMI (Nicola Huxley, Martin Hoyle, Tracey Jones-Hughes, Helen Coelho, Chris Cooper and Chris Hyde) as well as with experts in the field, including Dr Ian Frayling, with whom we keep close links. 

Many people will have heard of the BRCA gene mutations which lead to an increased risk of breast and ovarian cancer (particularly after Angelina Jolie revealed she was a carrier), but Lynch syndrome is much less well known although it plays a similar role to BRCA in bowel cancer and womb and ovarian cancers. There are likely to be over 150,000 people with Lynch syndrome in the United Kingdom, but the vast majority do not know they have it. If a person has Lynch syndrome there is a 50:50 chance they will pass it on to each of their children. It dramatically increases the risk of a number of cancers and leads people to develop cancer at an earlier age than average. 

We were commissioned by the NIHR Health Technology Assessment programme to investigate whether it would be effective and cost-effective to screen people developing bowel cancer at an early age (under 50 years) for Lynch syndrome. If Lynch syndrome is identified in a person their family can also be tested for the particular mutation. If people have Lynch syndrome (or are at risk but untested) then surveillance can be used to try to identify and remove pre-cancerous growths, as well as to catch cancer early. This surveillance has been shown to be effective for bowel cancer.

We reviewed the literature and constructed an economic model and found that it would be cost-effective to do this screening, potentially also up to age 70. We published our work in a monograph in the Health Technology Assessment journal (open access), but we also wanted to reach a wider audience by writing a short article for a journal, and to include further results about the predicted impact of screening on colonoscopy services. This was published in BMC Cancer (also open access) and we were delighted to be subsequently informed that our journal article was highly accessed.

Our interest in Lynch syndrome continues, and we are seeking funding to continue working in this area".

Congratulations to Tristan and colleagues in ESMI on your important findings for screening for Lynch syndrome, and your subsequent successful publication.