Post-acute COVID-19 complications in UK doctors: results of a cross-sectional survey

BACKGROUND

As a consequence of their occupation, doctors and other healthcare workers were at higher risk of contracting coronavirus disease 2019 (COVID-19), and more likely to experience severe disease compared to the general population. However, systematic information on post-acute COVID complications in doctors is very limited.

AIMS

This study aimed to determine the symptoms, perceived determinants, health and occupational impact, and consequent needs relating to post-acute COVID complications in UK doctors.

METHODS

An online cross-sectional survey was distributed to UK doctors self-identifying as having Long COVID or other post-acute COVID complications.

RESULTS

Of 795 responses, 603 fulfilled the inclusion criteria of being a UK-based medical doctor experiencing one or more post-acute COVID complications. Twenty-eight per cent reported a lack of adequate Respiratory Protective Equipment at the time of contracting COVID-19. Eighteen per cent of eligible respondents reported that they had been unable to return to work since acquiring COVID.

CONCLUSIONS

Post-acute COVID (Long COVID) in UK doctors is a substantial burden for respondents to our questionnaire. The results indicated that insufficient respiratory protection could have contributed to occupational disease, with COVID-19 being contracted in the workplace, and resultant post-COVID complications. Although it may be too late to address the perceived determinants of inadequate protection for those already suffering with Long COVID, more investment is needed in rehabilitation and support of those afflicted.

COVID-19 in Workplace Settings: Lessons Learned for Occupational Medicine in the UK

This paper addresses lessons learned from the COVID-19 pandemic from a UK Occupational Medicine perspective to permit comparison with other national accounts. In spite of good prior research and statute, the necessary resources to protect workers' health were seriously lacking when the pandemic struck. Weak public health guidance, which did not recognise dominant airborne transmission, was applied to workplaces, leaving workers and others unprotected, especially in respect to Respiratory Protective Equipment (RPE). The Health and Safety Executive (HSE) as regulator was lacking, for example, in not producing guidance to protect HealthCare Workers (HCW) who were amongst the most at risk. The UK COVID-19 Public Inquiry should address shortcomings such as these, but recommendations must be accompanied by robust means to ensure appropriate implementation. These should range from substantial measures to improve indoor air quality, to a permanent pandemic management organization with adequate resources. The enforcing authority has to be obliged to publish more specific workplace guidance than the public health authorities. Occupational medicine as a discipline needs to be better prepared, and hence to assert its responsibility towards high standards of workers' health protection. Future research has to include investigating the best means of mitigation against airborne infection and the management of post-acute covid sequelae.

An Epidemiological Study of Lung Cancer and Selected Other Cancers among Namibian Uranium Workers

The Rössing Uranium Limited (RUL) open-cast uranium mine in Namibia has operated since 1976. Studies of underground uranium miners from Europe and North America have shown increased cancer risks (principally lung cancer). We explored the association between radiation doses and selected cancers in RUL mineworkers. Employees with at least one-year of continuous employment between 1976 and 2010 were included. Incident cancer cases [lung, extra-thoracic airways (ETA), leukemia, brain and kidney] occurring before the end of 2015 were identified from the Namibian and South African National Cancer Registries, and RUL's occupational health provider. Using a case-cohort design, data on exposure and confounding factors were collected for all cancer cases among the study cohort and a stratified random sample (sub-cohort) of the cohort, including cases. Radiation doses were estimated based on annual dose records held by RUL. In total, 76 cancer cases (32 lung, 18 ETA, 8 leukemia, 9 brain, 9 kidney) and a sub-cohort of 1,121 sampled from 7,901 RUL employees were included. A weighted Cox model, adjusted for available known confounders, produced a rate ratio (95% CI) for lung cancer of 1.42 (0.42, 4.77) and 1.22 (0.26, 5.68), respectively, for medium and higher cumulative lung dose categories compared to the lower category, and 1.04 (0.95, 1.13) for a dose increase of 10 mSv. This study faced considerable challenges with respect to case ascertainment, exposure estimates, and ensuring accuracy of key variables. Persuasive consistent evidence for elevated cancer risk was not found for radiation or other exposures studied at the Rössing uranium mine.

Exploring Associations between Stressors and Burnout in Trainee Doctors During the COVID-19 Pandemic in the UK

OBJECTIVE

The authors examined associations between stressors and burnout in trainee doctors during the COVID-19 pandemic.

METHODS

An anonymous online questionnaire including 42 questions on general and pandemic-specific stressors, and the Maslach Burnout Inventory-Health Services Survey (MBI-HSS), was sent to 1000 randomly selected trainee doctors in North-West England. Main outcomes were burnout scores that were stratified into Emotional Exhaustion (EE), Depersonalisation (DP), and reduced Personal Accomplishment (PA) and associations between stressors and burnout using stepwise regression analysis.

RESULTS

A total of 362 complete responses were received giving a response rate of 37%. Mean scores for EE, DP, and PA derived from the MBI-HSS were 27.7, 9.8, and 34.3 respectively. Twenty-three stressors were found to be associated with burnout dimensions. "Increase in workload and hours due to COVID-19," "Poor leadership and management in the National Health Service," and "Not feeling valued" were found to have strong associations with burnout dimensions. Only "Not confident in own abilities" was found to be associated with all burnout dimensions.

CONCLUSIONS

Associations with burnout were found to be identified in a range of work, pandemic, and non-work-related stressors, supporting the need for multi-level interventions to mitigate burnout.

Cross-sectional study exploring the association between stressors and burnout in junior doctors during the COVID-19 pandemic in the United Kingdom

OBJECTIVES

This study aims to develop a comprehensive list of stressors relevant to junior doctors and will also report findings exploring the associations between burnout and stressors, which include work and non-work-related stressors as well as pandemic-related stressors.

METHODS

An anonymous online questionnaire was sent to 1000 randomly selected junior doctors in the North-West of England. The questionnaire included 37 questions on general and pandemic-specific stressors, and the Maslach Burnout Inventory Health Services Survey. The main outcomes of interest were junior doctor ratings of stressors and scores for burnout (emotional exhaustion [EE], depersonalisation [DP], and personal accomplishment [PA]). Stepwise regression analysis was undertaken to assess associations between stressors and burnout.

RESULTS

In total, 326 responses were collected (response rate = 33%). Of the top 10 stressors rated by junior doctors, 60% were related to the pandemic. Multiple stressors were found to be associated with the burnout dimensions. Fatigue (β = .43), pandemic-related workload increase (β = .33), and feeling isolated (β = .24) had the strongest associations with EE, whereas fatigue (β = .21), uncertainty around COVID-19 information (β = .22) and doing unproductive tasks (β = .17) had the strongest associations with DP. Working beyond normal scope due to COVID-19 (β = -.26), not confident in own ability (β = -.24) and not feeling valued (β = -.20) were found to have the strongest associations with PA.

CONCLUSIONS

Junior doctors experience a combination of general stressors and additional stressors emerging from the pandemic which significantly impact burnout. Monitoring these stressors and targeting them as part of interventions could help mitigating burnout in junior doctors.

On the importance of primary and community healthcare in relation to global health and environmental threats: lessons from the COVID-19 crisis

In the course of the COVID-19 pandemic, it has become clear that primary healthcare systems play a critical role in clinical care, such as patient screening, triage, physical and psychological support and also in promoting good community advice and awareness in coordination with secondary healthcare and preventive care. Because of the role of social and environmental factors in COVID-19 transmission and burden of disease, it is essential to ensure that there is adequate coordination of population-based health services and public health interventions. The COVID-19 pandemic has shown the primary and community healthcare (P&CHC) system’s weaknesses worldwide. In many instances, P&CHC played only a minor role, the emphasis being on hospital and intensive care beds. This was compounded by political failures, in supporting local community resilience. Placing community building, social cohesion and resilience at the forefront of dealing with the COVID-19 crisis can help align solutions that provide a vision of ‘planetary health’. This can be achieved by involving local well-being and participation in the face of any pervasive health and environmental crisis, including other epidemics and large-scale ecological crises. This paper proposes that P&CHC should take on two critical roles: first, to support local problem-solving efforts and to serve as a partner in innovative approaches to safeguarding community well-being; and second, to understand the local environment and health risks in the context of the global health perspective. We see this as an opportunity of immediate value and broad consequence beyond the control of the COVID-19 pandemic.

Occupational Asthma and Its Causation in the UK Seafood Processing Industry

Objectives

The processing of seafood (fish and shellfish) for human consumption can lead to health consequences, including occupational asthma (OA). Several non-UK studies have reported both respiratory outcomes and airborne levels of major allergens in seafood processing. However, there is a paucity of such evidence in the UK land-based seafood processing sector, which employs some 20 000 workers.

Methods

University of Manchester’s Surveillance of Work-related and Occupational Respiratory Disease (SWORD) reporting system has been interrogated over the period 1992–2017 to define the incidence rate of OA cases that can be ascribed to the UK land-based processing sector, and the seafood species implicated. Airborne allergen monitoring data undertaken at Health and Safety Executive’s laboratory from 2003 to 2019 have also been collated.

Results

The estimated annual OA incidence rate in seafood processors was 70 [95% confidence intervals (CIs) 48.9, 91.1] per 100 000 workers compared with 2.9 (95% CIs 2.8, 3.1) in ‘all other industries’. The annual calculated percentage trend in OA (1992–2017) was −8.1% (95% CIs −15.9, 0.4) in seafood processing showing a similar trend to ‘all other industries’ (mean −7.0%; 95% CIs −7.8, −6.1). Prawns and salmon/trout were notably implicated by SWORD as causative species related to OA. There is a general paucity of available UK airborne allergen monitoring data, particularly concerning processing salmon or trout. Available airborne monitoring for salmon parvalbumin in seven processors ranged between the limit of detection and 816 ng m⁻³ (n = 64). Available air monitoring levels of the major shellfish allergen (tropomyosin) during processing of crabs and prawns ranged between 1 and 101 600 ng m⁻³ (n = 280), highlighting that high levels of exposure can occur.

Conclusions

These data show an excess incidence of OA in the UK seafood processing industry during 1992–2017, with limited airborne monitoring data for the processing of prawn, crab, and salmon suggesting that significant exposure to major seafood allergens can occur in this industry. Further investigation of current levels of respiratory ill-health and the sources of allergen exposure are warranted.

Sentinel approach to detect emerging causes of work-related respiratory diseases

BACKGROUND

The world of work is continually changing, and this could result in new and emerging risks being introduced, including those that may cause work-related respiratory diseases (WRRD).

AIMS

To describe recently emerging and new cases of WRRD and the relevant methodology using data in a national occupational respiratory disease surveillance scheme in the UK.

METHODS

Incident cases of respiratory diseases reported by physicians to the Surveillance of Work-related and Occupational Respiratory Disease (SWORD) between January 2015 and December 2017 were included. Potentially emerging respiratory hazards manifesting in SWORD data were identified with the following hierarchical approach: (i) new respiratory disease not previously associated with work, (ii) specific exposure/agent not previously associated with WRRD and (iii) industry and/or occupation not previously associated with WRRD.

RESULTS

A total of 1215 cases of WRRD were reported to SWORD between January 2015 and December 2017. No new WRRD were identified. Thirteen potentially emerging causes of occupational asthma were identified, including exposures to agents such as ninhydrin. Four potential new causes were identified for interstitial pneumonia, which included wood and brass dust. Two potentially emerging causes of WRRD were identified for inhalational accidents (green coffee and nitrocellulose), hypersensitivity pneumonitis (diphenylmethane diisocyanate and salami mould), rhinitis (morphine and Amaranthus quitensis) and sarcoidosis (prions and horses).

CONCLUSIONS

Continuous monitoring and reporting of any new work-related disease is a critical function of any occupational disease reporting scheme. Potential emerging causes of work-related health risks have been identified by using a simple and systematic way of detecting emerging causes of WRRDs.

Factors Associated With Burnout and Stress in Trainee Physicians: A Systematic Review and Meta-analysis

IMPORTANCE

Evidence suggests that physicians experience high levels of burnout and stress and that trainee physicians are a particularly high-risk group. Multiple workplace- and non-workplace-related factors have been identified in trainee physicians, but it is unclear which factors are most important in association with burnout and stress. Better understanding of the most critical factors could help inform the development of targeted interventions to reduce burnout and stress.

OBJECTIVE

To estimate the association between different stressors and burnout/stress among physicians engaged in standard postgraduate training (ie, trainee physicians).

DATA SOURCES

Medline, Embase, PsycINFO, and Cochrane Database of Systematic reviews from inception until April 30, 2019. Search terms included trainee, foundation year, registrar, resident, and intern.

STUDY SELECTION

Studies that reported associations between stressors and burnout/stress in trainee physicians.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers extracted the data and assessed the quality of the evidence. The main meta-analysis was followed by sensitivity analyses. All analyses were performed using random-effects models, and heterogeneity was quantified using the I2 statistic.

MAIN OUTCOME AND MEASURES

The main outcome was the association between burnout/stress and workplace- or non-workplace-related factors reported as odds ratios (ORs) and their 95% CIs.

RESULTS

Forty-eight studies were included in the meta-analysis (n = 36 266, median age, 29 years [range, 24.6-35.7 years]). One study did not specify participants' sex; of the total population, 18 781 participants (52%) were men. In particular, work demands of a trainee physician were associated with a nearly 3-fold increased odds for burnout/stress (OR, 2.84; 95% CI, 2.26-3.59), followed by concerns about patient care (OR, 2.35; 95% CI, 1.58-3.50), poor work environment (OR, 2.06; 95% CI, 1.57-2.70), and poor work-life balance (OR, 1.93; 95% CI, 1.53-2.44). Perceived/reported poor mental or physical health (OR, 2.41; 95% CI, 1.76-3.31), female sex (OR, 1.34; 95% CI, 1.20-1.50), financial worries (OR, 1.35; 95% CI, 1.07-1.72), and low self-efficacy (OR, 2.13; 95% CI, 1.31-3.46) were associated with increased odds for burnout/stress, whereas younger age and a more junior grade were not significantly associated.

CONCLUSIONS AND RELEVANCE

The findings of this study suggest that the odds ratios for burnout and stress in trainee physicians are higher than those for work-related factors compared with nonmodifiable and non-work-related factors, such as age and grade. These findings support the need for organizational interventions to mitigate burnout in trainee physicians.

A Qualitative Study Exploring the Determinants, Coping, and Effects of Stress in United Kingdom Trainee Doctors

OBJECTIVES

Evidence suggests United Kingdom trainee doctors are experiencing high levels of stress; however, little is known about what determinants contribute to stress, coping mechanisms to mitigate stress, and the effects of stress are in current trainee doctors. Hence, this study aims to explore the determinants, coping mechanisms as well as the effects of stress in this group.

METHODS

Focus groups were undertaken with trainee doctors in North West England to better understand the determinants, coping mechanisms, and effects of stress. Informed written consent was obtained and focus groups were recorded and transcribed. Transcriptions were analyzed using QSR NVivo v11.

RESULTS

A total of 44 trainee doctors participated in 11 focus groups. Respondents comprised UK graduates and international medical graduates, across all stages of training in a range of different specialties. Four main themes were identified as determinants: (1) Expectations and guilt, (2) Feeling undervalued, (3) Managing uncertainty and risk, (4) Work environment. Four main themes were identified as coping mechanisms: (1) Reflection and insight, (2) Work-life balance, (3) Work and training environment, (4) Development as a doctor. Two main themes were identified as effects of stress: (1) Negative outcome on wellbeing, (2) Outcome on career.

CONCLUSIONS

A range of determinants contributes to stress in trainee doctors and they utilize a range of mechanisms to cope. Stress in their working lives can also affect their wellbeing and careers. These findings could be used to improve the understanding of stress in trainee doctors and assist in the development of supportive interventions.

Building a job-exposure matrix for early plutonium workers at the Sellafield nuclear site, United Kingdom

The potential for adverse health effects from internal exposure to Plutonium has been recognised since its discovery in the 1940s. However, in the absence of specific information, potential risks from Plutonium exposure have always largely been controlled through knowledge of radiation exposure risks in general, much of which comes from external radiation exposures. To try to obtain more direct estimates of potential internal exposure risks, epidemiological studies of Plutonium workers need to be conducted. Such epidemiological analyses require individual Plutonium exposure estimates that are as accurate and unbiased as possible. The UK Sellafield workforce includes one of the world's largest cohorts of Plutonium workers, which constitutes, by some considerable margin, the group of workers most comprehensively monitored for internal exposure to this alpha-particle-emitter. However, for several hundred workers employed at the start of Plutonium work at the facility, during the period from 1952 through to 1963, the historical urinalysis results available cannot provide sufficiently accurate and unbiased exposure assessments needed for use in epidemiological studies. Consequently, these early workers have had to be excluded from epidemiological analyses and this has significantly reduced the power of these studies. A promising quantitative methodology to overcome the issue of missing or deficient exposure data, is to use exposure data from other sources to estimate the average exposure a 'typical worker' would have received, and to collate this information for specific occupations and years. This approach is called a Job-Exposure Matrix (JEM). Work on a pilot study to construct a population-specific quantitative JEM for the early Plutonium workers at Sellafield during 1952-1963, for whom reliable urinalysis results do not exist, has shown the potential for a JEM approach to produce more reliable and useful exposure estimates for epidemiological research.

A review of non-glove personal protective equipment-related occupational dermatoses reported to EPIDERM between 1993 and 2013

BACKGROUND

Personal protective equipment (PPE) is defined as equipment that protects the wearer's body against health/safety risks at work. Gloves cause many dermatoses. Non-glove PPE constitutes a wide array of garments. Dermatoses resulting from these have hitherto not been documented.

OBJECTIVES

To determine the incidence and types of non-glove PPE-related dermatoses.

PATIENTS/METHODS

We analysed incident case reports from dermatologists of non-glove PPE-related dermatoses to a UK-wide surveillance scheme (EPIDERM) between 1993 and 2013.

RESULTS

The dermatoses associated with non-glove PPE accounted for 0.84% of all occupational skin disease. Of all PPE-related cases, 194 (9.2%) were attributable to non-glove PPE. Of these, 132 (68.0%) occurred in men, and the median age (both male and female) was 42 years (range 18-82 years). The non-glove PPE-related dermatoses were diagnosed as: allergic contact dermatitis (47.4%), irritant contact dermatitis (16.0%), friction (11.3%), occlusion (11.3%), unspecified dermatitis (8.8%), acne (3.1%), infections (1.5), and contact urticaria (0.52%). The industries most associated with non-glove PPE-related dermatoses were manufacturing (18.6%), public administration and defence (17.0%), health and social work (15.5%), and transport, storage, and communication (9.8%).

CONCLUSIONS

Clothing, footwear, facemasks and headgear need to be recognized as causes of dermatoses occurring at body sites less commonly associated with occupational skin disease.

Occupational asthma caused by an epoxy amine hardener

We describe a 43-year-old epoxy floor layer who developed work-related asthma while exposed to an epoxy hardener based on isophorone diamine (IPDA). Challenge exposures to the curing of the epoxy resin system and subsequently to the polyfunctional amine hardener containing IPDA both elicited delayed asthmatic reactions. This report further indicates that exposure to epoxy hardeners containing polyfunctional amines should be considered as a potential cause of occupational asthma. Appropriate work hygiene measures should be implemented to minimize airborne exposure to these volatile compounds.

Occupational exposure factors for mental and behavioral disorders at work: The FOREC thesaurus

Background

Mental disorders in the workplace are a major public health problem. Knowledge of the impact of the psychosocial work environment on mental and behavioral disorders can assist occupational physicians in the identification and description of occupational risk situations, and help to define priority actions. However, no classification for occupational exposure factors is currently available. We aimed to build a thesaurus of “Organizational, Relational, Ethical and other Contributing Factors” (FOREC) linked with the onset of mental and behavioral disorders.

Methods

The French Agency for Food, Environmental and Occupational Health and Safety (ANSES) initiated and supervised a multidisciplinary working group consisting of the representatives of the main French occupational and public health actors. All decisions were accepted on a consensus basis. This collaborative work led to the classification of occupational exposure factors for mental and behavioral disorders in the workplace. To test this thesaurus in clinical practice, a French multicenter study was implemented. Patients were workers referred to the Occupational Disease Centers for mental health issues at work. Factors contributing to mental and behavioral disorders among workers were identified and coded retrospectively from the worker’s point of view using the FOREC thesaurus.

Results

We recruited 323 workers, aged 44.9±9.2 years, of which 31.3% were men. The most commonly encountered disorders were generalized anxiety disorders (106 workers, 32.8%) and moderate depressive episodes (86 workers, 26.7%). We identified 1357 factors, i.e. an average of 4.2 factors per worker. Among them, 575 (42.4%) were relational and 515 (37.9%) were organizational. All factors identified during consultations were described in the thesaurus.

Conclusions

We built the first thesaurus of “Organizational, Relational, Ethical and other Contributing Factors” (FOREC) that may help to generate profiles of mental and behavioral disorders at work. Encoding and describing these exposure factors, as well as using a worldwide standardized and shared terminology, will help to identify specific workplace prevention programs.

The preventable burden of work-related ill-health

Background

The fraction of ill-health overall attributable to occupational conditions has not been extensively evaluated, thus contributing to the perception of a lesser relevance of education and research in occupational health in respect to other fields of medical research and practice.

Aims

To assess the relevance of work-related conditions on the aetiology of human ill-health in different health domains.

Methods

We extracted the risk estimates associated with heritability and with occupational risk factors for chronic lymphocytic leukaemia (CLL), major depressive disorder (MDD) and long QT syndrome (LQTS) from 13 published international reports. The selection criteria for the eligible studies were: genome-wide studies, or studies of the occupational risk factors associated with one of the three diseases of interest. We calculated and compared the respective population attributable fraction for the combined occupational risk factors, and for heritability.

Results

We estimated that occupational risk factors would account for 12% (95% confidence interval (CI) 4-19) of CLL, 11% (95% CI 7-15) of MDD and 10% (95% CI 2-13) of LQTS burden in the general population. The corresponding figures for heritability would be 16% (95% CI 11-22), 28% (95% CI 20-5) and 17% (95% CI 7-27).

Conclusions

More efforts in capacity building and research in occupational health are warranted aiming to prevent ill-health and to preserve a productive life for the ageing work population.

Collaborative case management to aid return to work after long-term sickness absence: a pilot randomised controlled trial

Background

Despite high levels of employment among working-age adults in the UK, there is still a significant minority who are off work with ill health at any one time (so-called ‘sickness absence’). Long-term sickness absence results in significant costs to the individual, to the employer and to wider society.

Objective

The overall objective of the intervention was to improve employee well-being with a view to aiding return to work. To meet this aim, a collaborative case management intervention was adapted to the needs of UK employees who were entering or experiencing long-term sickness absence.

Design

A pilot randomised controlled trial, using permuted block randomisation. Recruitment of patients with long-term conditions in settings such as primary care was achieved by screening of routine records, followed by mass mailing of invitations to participants. However, the proportion of patients responding to such invitations can be low, raising concerns about external validity. Recruitment in the Case Management to Enhance Occupational Support (CAMEOS) study used this method to test whether or not it would transfer to a population with long-term sickness absence in the context of occupational health (OH).

Participants

Employed people on long-term sickness absence (between 4 weeks and 12 months). The pilot was run with two different collaborators: a large organisation that provided OH services for a number of clients and a non-profit community-based organisation.

Intervention

Collaborative case management was delivered by specially trained case managers from the host organisations. Sessions were delivered by telephone and supported use of a self-help handbook. The comparator was usual care as provided by participants’ general practitioner (GP) or OH provider. This varied for participants according to the services available to them. Neither participants nor the research team were blind to randomisation.

Main outcome measures

Recruitment rates, intervention delivery and acceptability to participants were the main outcomes. Well-being, as measured by the Clinical Outcomes in Routine Evaluation Outcome Measure (CORE-OM), and return-to-work rates were also recorded.

Results

In total, over 1000 potentially eligible participants were identified across the sites and invited to participate. However, responses were received from just 61 of those invited (5.5%), of whom 16 (1.5%) were randomised to the trial (seven to treatment, nine to control). Detailed information on recruitment methods, intervention delivery, engagement and acceptability is presented. No harms were reported in either group.

Conclusions

This pilot study faced a number of barriers, particularly in terms of recruitment of employers to host the research. Our ability to respond to these challenges faced several barriers related to the OH context and the study set up. The intervention seemed feasible and acceptable when delivered, although caution is required because of the small number of randomised participants. However, employees’ lack of engagement in the research might imply that they did not see the intervention as valuable.

Future work

Developing effective and acceptable ways of reducing sickness absence remains a high priority. We discuss possible ways of overcoming these challenges in the future, including incentives for employers, alternative study designs and further modifications to recruitment methods.

Trial registration

Current Controlled Trials ISRCTN33560198.

Funding

This project was funded by the NIHR Public Health Research programme and will be published in full inPublic Health Research; Vol. 6, No. 2. See the NIHR Journals Library website for further project information.