Article Text

Barriers to identifying occupational asthma among primary healthcare professionals: a qualitative study
  1. Gareth I Walters1,2 and
  2. Christopher M Barber3
  1. 1Regional NHS Occupational Lung Disease Service, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
  2. 2Occupational and Environmental Medicine, University of Birmingham, Birmingham, UK
  3. 3Centre for Workplace Health, Northern General Hospital, Sheffield, UK
  1. Correspondence to Dr Gareth I Walters; gareth.walters{at}


Introduction Occupational asthma (OA) accounts for one in six cases of adult-onset asthma and is associated with a large societal cost. Many cases of OA are missed or delayed, leading to ongoing exposure to the causative agent and avoidable lung function loss and poor employment-related outcomes. Enquiry about work-related symptoms and the nature of work by healthcare professionals (HCPs) is limited, evident in primary and secondary care. Potential reasons cited for this are time pressure, lack of expertise and poor access to specialists.

Aim To understand organisational factors and beliefs and behaviours among primary HCPs that may present barriers to identifying OA.

Methods We employed a qualitative phenomenological methodology and undertook 20–45 min interviews with primary HCPs in West Midlands, UK. We used purposive and snowball sampling to include general practitioners (GPs) and practice nurses with a range of experience, from urban and rural settings. Interviews were recorded digitally and transcribed professionally for analysis. Data were coded by hand, and thematic analysis was undertaken and determined theoretically until themes were saturated.

Results Eleven HCPs participated (eight GPs, three nurses). Four themes were identified that were considered to impact on identification of OA: (1) training and experience, (2) perceptions and beliefs, (3) systems constraints, and (4) variation in individual practice. OA-specific education had been inadequate at every stage of training and practice, and clinical exposure to OA had been generally limited. OA-specific beliefs varied, as did clinical behaviour with working-age individuals with asthma. There was a focus on diagnosis and treatment rather than attributing causation. Identified issues regarding organisation of asthma care were time constraints, lack of continuity, referral pressure, use of guidelines and templates, and external targets.

Conclusion Organisation and delivery of primary asthma care, negative OA-related beliefs, lack of formal education, and exposure to OA may all currently inhibit its identification.

  • asthma
  • occupational lung disease
  • asthma in primary care
  • asthma epidemiology
  • asthma guidelines

Data availability statement

Data are available upon reasonable request.

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Key messages

  • Asthma care may not be organised in a way that supports attribution of an occupational cause.

  • Primary healthcare professionals involved in delivering asthma care lack training and clinical experience in OA and display negative beliefs about its occurrence.

  • We have identified four themes that present barriers to identifying OA in primary care and

  • made recommendations for medical education and for clinical practice based on these findings.


Occupational asthma (OA) is defined as asthma caused by inhalation of an agent encountered at work. Most cases occur following exposure to a respiratory sensitising agent, and a number of high-risk occupations are described (eg, bakers, paint sprayers). OA is relatively common among working-age individuals with asthma (population attributable fraction: 16%1), and despite regulatory activity in the UK aiming to prevent its occurrence the incidence has increased over the last 10 years,2 with novel agents frequently reported.3 Estimates suggest that OA costs the UK £1.1 billion each decade in terms of healthcare costs, job loss and state benefits.4 Early recognition of OA, and removing the affected individual from the causative exposure, offer the best chance of a full recovery.5 UK asthma guidelines recommend that healthcare professionals (HCP) ask adults with new-onset or reactivated childhood asthma symptoms about the work-relatedness of their symptoms and the nature of their work, in order to screen for OA.6 OA should be excluded in those with work-related asthma symptoms, usually achieved via referral to a respiratory specialist with expertise in diagnosing OA (a handful of such specialists exist7).

In the UK, OA is under-reported to surveillance schemes8 and under-recognised by HCPs. This is evident in primary care, where the prevalence of clinician-diagnosed OA is much lower than expected among working-age individuals with asthma.9 10 Furthermore, there are lengthy delays between symptom onset and diagnosis of OA (median 4 years), which may lead to adverse health and employment outcomes.11 12 Patients with OA lack awareness and understanding of the nature of work-related symptoms, and some are reluctant to seek help for fear of job or financial loss.13 14 Enquiry about the nature of work and work-related symptoms by primary HCPs is limited, and insufficient time, lack of expertise and poor access to specialist services have been cited as reasons for this.15–18 However, the factors that determine how HCPs behave when consulting working-age individuals with asthma, and the barriers to enquiry about work-related asthma symptoms, have not been studied in detail.

Aim of the study

The aim of this study was to explore and understand organisational factors and beliefs and behaviours among primary HCPs, which may present barriers to identifying OA in primary care.


Reporting of study methods and results was undertaken according to the Standards for Reporting Qualitative Research.19

Study design

The study employed a phenomenological approach, in the interpretative tradition, using qualitative analysis of interviews with primary HCPs.


Interviews were undertaken with HCPs currently working at UK primary care practices in West Midlands, within 40 kilometres of the lead author’s institution (radius chosen for convenience).

Eligibility criteria

Any practising, fully qualified general practitioner (GP) or practice nurse attending working-age patients with asthma was deemed eligible for the study. All participants were required to speak English during their interview.

Sample selection

Purposive sampling was undertaken, targeting GPs and practice nurses from urban and rural settings who were likely to have a range of experience with working-age individuals with asthma during their training and practice. Further snowball sampling of professional acquaintances was also undertaken, by asking participants identified via educational seminars to recommend colleagues.

Participant recruitment

The number of participants was determined by saturation of themes, although it was expected to be less than 15, since a small number has previously been deemed adequate for narrow research questions.20 The primary author had delivered free educational seminars on work-related lung disease, specifically for primary HCPs, since 2015; during seminars undertaken in late 2018, attendees were given an email address to contact if they were interested in participating in the study. Inducements of £75 were offered to any HCP attempting the interview, except for participant 1. Participant 1 was the wife of the lead author and her interview was undertaken as a pilot, in order to check audio and comprehension of question phrasing. Preinterview, there was no intention to include its data, although once completed the authors felt that it yielded data worthy of inclusion in the analysis. Participant 1 highlighted the study among professionals (participants 2 and 3) from the same practice group, who were subsequently included. Additionally, participants 8, 9 and 10 were snowball-sampled from the same practice as participant 6.

Data collection

All interviews were undertaken face to face by the primary author at participants’ homes or places of work; written informed consent was sought preinterview. Interviews lasted between 20 and 45 min and were conducted according to a semistructured schedule written by the primary author, based on his clinical experience, with previously published data in mind (online supplemental file 1). All interviews were audio-recorded using a hand-held digital Dictaphone; no file notes were taken.

Data transcription

Digital audio files were transcribed by a professional typist. Standard UK written English was used and common abbreviations preagreed. The actual words used (including acronyms, abbreviations, slang, aborted sentences) were transcribed, but since conversation analysis was deemed less important in this study, other nuances of talk were not included (eg, non-verbal features, intonations, stutters). Social conversation before and after each interview was not transcribed.

Thematic analysis

The interview transcriptions were analysed by the primary author, with coinvestigator CMB acting as a critical friend.21 22 Open coding was undertaken (no pre-existing codes, developed and modified throughout coding process).23 24 Analysis was predominantly theoretical, answering the research question, rather than inductive. A preliminary analysis was undertaken by the primary author after seven interviews, and domains that required further enquiry were highlighted. Further interviews were undertaken aiming for saturation of themes.


The interviewer (GIW) was a 43-year-old, male, white British National Health Service (NHS) consultant physician with a specialist interest in OA. He was trained in hospital medicine in the late 1990s–early 2000s and had no personal experience of working in primary care. GIW had preconceived ideas about the cause of poor or delayed identification, through his own training, clinical observations and previous research undertaken; he was potentially unknowing of many organisational aspects of primary care at the time the study was undertaken.


Descriptive analysis

Eleven HCPs participated in the study (summarised in table 1), comprising four female and four male GPs (median experience 17 years) and three practice nurses (median experience 23 years). Of the six individuals who made contact following a seminar, all consented and became participants.

Table 1

Summary of participant healthcare professionals undertaking semistructured interviews with the researcher

Qualitative analysis

Four themes impacting on whether HCPs were likely to suspect and investigate patients for OA were identified: (1) training and experience, (2) perceptions and beliefs, (3) systems constraints, and (4) variation in individual practice (summarised in table 2).

Table 2

Summary of themes, subthemes and codes derived from analysis of interviews with GPs and practice nurses

Theme 1: training and experience

Six out of eight GPs described little or no formal exposure to OA during undergraduate or postgraduate study. Three GPs recognised that occupational respiratory disease featured during their undergraduate study, although the focus was not OA (eg, pneumoconiosis, mesothelioma). Eight GPs gained continuous professional development (CPD) by attendance at a short general topic update course, which included asthma management; two GPs recalled that OA was mentioned, although stressed that the emphasis was on diagnosis of asthma and its treatment. Two nurses described having little formal training in asthma management, with no emphasis on OA, since beginning their professional roles.

(re: undergraduate education) I can just imagine it was like one lecture with a table or something that you probably learn for an exam and never refer to again, and it didn’t feel like it’s an inherent part of your assessment of respiratory disease. (P3)

In current roles, three GPs had no experience of OA at all and five GPs or nurses described some limited experience. Three GPs suggested that their experiential learning in asthma depended on previous job specialty, content of training rotations, and expertise and interests of trainers and colleagues. Three HCPs cited personal or family experiences as influences on their current understanding of asthma and OA. All participants noted that primary care had changed to include specialist areas of practice, with nurses, nurse practitioners and dedicated GPs taking on greater responsibilities for chronic respiratory disease diagnosis and management (see online supplemental file 2).

Well we’ve seen people who you can see there’s a correlation there, they seemed to have never had a problem and suddenly they’re struggling, and there is definite link there. So yeah, I can’t think I’ve seen lots of people, but I’ve probably seen a handful of people like that. (P3)

And all of us have had other influences. Because I have to admit, my asthma management is influenced by our eldest, who had asthma reasonably badly as a child and they grow out of it. So I find that my individual experience of how people deal with it almost informs me. (P2)

Theme 2: perceptions and beliefs

Four GPs stated that they lacked OA subject knowledge, and one perceived OA to be a specialist subject, out of scope for general practice. Four GPs found it difficult to contextualise information gathered about exposures. Two GPs believed knowledge work and office environments carried no risk for OA.

I don’t know if GPs would have any knowledge of what it might be that’s causing their asthma… Very occasionally, they’ll [patients] come with a leaflet of all the chemicals they use but I don’t understand that any more than they do…that’s one of the reasons we are GPs because we don’t want to deal with something in great detail day in and day out. That’s not the sort of people we are. (P4)

And you know, you start on the wards and you’ve got your list of questions, systems review stuff isn’t it, and pets and pigeons and all that kind of stuff… it felt irrelevant at the time. But it was on your list so you just blindly ask it without perhaps thinking ‘Why am I asking these questions?’ (P3)

Beliefs about the occurrence of OA are detailed in table 3; many of these imply that OA has little impact on society, locality or on individual practice. However, seven HCPs recognised health and employment benefits for affected individuals, comprising certainty and clarity of diagnosis, validation of symptoms and ill health, symptom and functional improvements, and retention of employment and income. Workforce and public health benefits were also cited: identifying novel causes, controlling local outbreaks and avoiding similar harms to other workers. Eight HCPs saw jeopardy in making a diagnosis of OA, including inducing fear of and actual job loss, difficulty finding alternative, unexposed skilled work, and false diagnoses leading to avoidable job loss. The majority of HCPs believed that involving specialists (either respiratory or occupational health) added value over primary care, in terms of complexity of diagnosis, time resource required, interpretation of tests and managing the workplace aspects. Opinions varied on where the responsibility for identifying OA lay and the role of primary care:

Our job is just to point people in the right direction. I think the idea that GPs are going to make these diagnoses and have the knowledge to know what to do with it… it is complex stuff, isn’t it? (P4)

Table 3

Beliefs about the occurrence of OA

If you define what it is and you can somehow avoid the trigger and therefore everything is fine and you can just do your standard sort of approach to treatment and everything seems stable, then yeah, I think it’s fine to absorb that in general practice. (P3)

I’m assuming there is legislation around occupational asthma and hazards… So, I’d kind of feel like I was out of my depth. And I suppose that’s where I’d see the shared care bit really, is the occupational team looking after that and the general health with me. (P7)

Theme 3: systems constraints

A number of issues were identified around the organisation of services, either nationally or locally, generically or specific to asthma care.

Lack of continuity

One GP suggested that patients were no longer interested in durable doctor–patient relationships. One GP reflected on a progressively ‘shallower’ understanding of her patients’ lives due to time pressure. One GP reported that the combination of short appointment times and lack of continuity between HCPs had led to repetition of enquiry and investigation, which would impede attributing causation for asthma.

Time pressure

Nine HCPs cited time pressure as a barrier to recognising OA, with many prioritising asthma diagnosis and medical treatment over cause attribution. Two described the experience as ‘inadequate’ or ‘feeling like survival’.

That’s why I don’t now work for the NHS because I refuse to do an inadequate job and the time given is inadequate and it doesn’t allow you to do things properly. (P5)

However one GP disagreed somewhat:

Yeah, our days are longer, but I don’t think I’m less likely to make that diagnosis because I’m so time poor with the patient any more than I used to be. (P11)

Guidelines and clinic templates

There was no knowledge or use of OA-specific guidelines among HCPs, but four HCPs recalled sections on OA in generic asthma guidelines. Some suggested that use of asthma-related guidelines varied between practices and/or individuals, and any protocols were subject to external influences, such as area prescribing committees, or locally commissioned asthma care standards. Four GPs described using clinic templates designed locally or adapted from published templates, although made no reference to OA or work.

And I know certainly on whatever template we’ve got, there isn’t a question about work, what is work or are your symptoms worse at work, which probably we do need to think about doing that. I wonder if maybe that could be some of the mismatch between us seeing it, it not ending up in secondary care. (P3)

External targets

The national quality programme for primary care, the Quality Outcomes Framework (‘QOF’), was identified by almost all HCPs as the major influence on organisation and delivery of primary care asthma services, and in turn how and which data were captured: exclusively electronically, usually via a template, and with a focus on data essential for QOF (asthma control questionnaires, treatment strategy); however, on occasion, there appeared to be local variation in QOF requirement. For some HCPs this was perceived as a ‘tick-box’ exercise or income-oriented, and not individual patient outcome-centred.

We’ll go through the proforma, look at their symptoms and do their Asthma Control Test, and if it all seems okay, we’ll say, ‘Right, carry on’. There’s no incentive to make a diagnosis of occupational asthma. (P4)

You are driven in part by what QOF requires you to do and it might have a template with multiple boxes on it and one of those could well be ‘Did you ask about occupational asthma?’. But if it’s not QOF-able and the patient’s saying ‘I’m fine, doctor’, I’m not touching that. (P11)

External pressures on referral

There was consensus among all seven HCPs who commented that referring a case of suspected OA to a specialist would be ‘reasonable’, defined variously in terms of rarity of disease, complexity of investigation and management; that is, the referral added ‘value’ over primary care, but was also acceptable under scrutiny from colleagues or other agencies. Most HCPs perceived pressure on their referral practice; some, not all, had referrals ‘monitored’ within the practice or clinical commissioning group (CCG) and were keen to avoid referrals deemed unnecessary (ie, specialist unlikely to add value), or appearing to have too low an index of suspicion for diagnosis, and being an outlier within the practice (more referrals than their colleagues) or CCG (more referrals than average).

I think we all feel under pressure to reduce referrals, because we are under pressure to reduce referrals. So, we now have a referrals MDT every week, and we look for ways that we can perhaps manage the patient within the practice, or avoid an unnecessary referral … All of our thresholds for referring anything that is not suspected cancer has had to go up. (P1)

Theme 4: variation in individual practice

Clinical enquiry

Of 11 HCPs who commented on their own clinical enquiry, 5 would unconditionally ask individuals with asthma about work-related symptoms, 4 conditionally (uncontrolled or new adult-onset symptoms, in a high-risk job) and 2 not at all. Seven HCPs commented on enquiry about occupation and the nature of work: four would ask unconditionally, two would not routinely ask, and one conditionally, only in the context of new-onset asthma. Two GPs described a tendency not to revisit the cause once a diagnosis of asthma had been made.

It’s not something that I’ve really thought about before if I’m honest. I tend to focus on the house, like is it dusty, have you got a cat, have you got dogs, have you got birds? Not so much the job. I’ve not come across it because I wouldn’t normally ask. (P10)

I wouldn’t say that I’m proactively asking questions but what I do find is that patients are quite well aware when there is something that triggers their problems. They do figure it out usually and they will tell you. (P9)

Referral thresholds

Of six GPs that commented, three would make a referral based on a suggestive medical history only, and three would want further investigations first (peak flow measurements). Qualities of a good referral were cited as: tests or opinion required but unavailable in primary care, a positive diagnosis of OA likely, meets specialist’s (presumed) expectation that ‘basic’ tests had already been carried out.

I think the idea of doing occupational peak flows and all the rest of it… we don’t have the wear-with-all to do it, to be honest, or the time to explain to the patient. We have seven [minutes]… our job is to be more aware and screen for the patients and then refer on, I guess. (P4)

You know, you don’t want to be too quick on the trigger on referral… We’ve been brought up with the ‘history, examination, investigation’ model, and I think you are duty-bound as the GP to try your best to put it on a plate for the consultant. (P11)

Referral practice

Three of four HCPs that commented were unaware of any regional referral centre for occupational lung diseases, and one believed that they would be unable to refer directly, needing to send patient to a local respiratory service first. Eight HCPs reflected on their own referral practice, which in all cases would be to refer a patient with suspected OA to a local secondary care provider first. Three HCPs mentioned that they might access their local electronic ‘Advice and Guidance’ service.

We just do it electronically now. There is a slight frustration because it is quite difficult sometimes to pick your consultant of choice. If I wanted you [interviewer], particularly, to see the patient, it’s not that easy. (P4)


Limitations and generalisability

Four distinct themes were identified, although others unknown to the researchers due to their background in hospital medicine, and not considered by the interviewees, could have been missed. Only one salaried GP was included and no doctors-in-training, who may have had a different perspective on training, although the range of experience of GPs was in fact broad (4–34 years). The study was sufficient to highlight the effect of differences in experience and training among GPs, although all routes through GP training are unlikely to have been accounted for, given the limited sample size. The small number of practices included and their geographical location (West Midlands) may also limit generalisability of findings, relating to training and local operating procedures. Many participants may be considered enthusiasts, having attended an evening symposium on OA, leading to selection bias (although there are in fact many reasons why HCPs do so). There was also therefore some preconditioning on the subject of interest, although most participants qualified their thoughts and behaviours as relating to presymposium (no explicit direction on this had been given before the interview). In order to increase truthfulness, thematic analysis was undertaken with a critical friend (CMB) and an audit trail was created for coding and organisation of themes. Interviews were undertaken at participants’ convenience, and they were encouraged to talk truthfully and openly, although ultimately some may have been reluctant to talk about aspects of their individual practice, if they perceived these to be different from others or ‘wrong’. Generally, however, these were felt to be generous and truthful accounts.

Training and experience

There was little focus on OA, or indeed on occupational health aspects of disease, evident during formal periods of training. Descriptive knowledge learnt tended to relate to asbestos, coal dust or non-specific pollutants (eg, dust, fumes), and not agents or jobs specific to OA; many GPs were unclear what to do with information gathered about occupational exposures, in the context of asthma. Process-oriented targets for asthma, and CPD seemingly aligned to these, are currently focused on objective diagnosis, establishing treatment and good asthma control (all worthwhile goals per se), but have deprioritised finding a cause. From the medical literature, physicians self-report low awareness of OA and lack OA-specific education, and cite complexity (too many causes, detailed occupational history required) as a barrier to diagnosis.17 25 Thus, in acute hospital and primary care there is little clinical enquiry about OA, and opportunities to detect OA are missed.26–28 An evidence-based e-learning module on OA can increase knowledge and use of guidelines among primary HCPs.15

Individual beliefs and practice

Many negative beliefs about the occurrence of OA and its social impact were evident and are likely to inhibit clinical enquiry. Parhar et al17 reported two factors leading physicians to attribute asthma to work: other work colleagues are affected, or the physician had previously attended a case due to the same causative agent. The perception of low prevalence of OA may be self-fulfilling since a missed diagnosis may not subsequently be recognised at all. The societal burden of OA is in fact high,4 and the incidence has not decreased since new causes and ‘at-risk’ industries emerge, as others disappear.2

Referral practice was predisposed by individual beliefs about the worth of a referral, that is, whether it reached thresholds of ‘acceptability’ and ‘quality’ described earlier, in part influenced by external pressures. However, all participants that commented saw advantages for specialist referral of suspected OA, due to the complexity and uncertainty of both diagnosis and management. Most HCPs would refer cases to a local secondary care physician, either through unawareness of an NHS occupational lung disease service (which may be a local phenomenon) or because local policy dictated so. A model explaining the variation in individual behaviour and potential barriers to identifying OA is shown in figure 1.

Figure 1

A conceptual model describing extrinsic factors and individual healthcare professional-oriented influences on missed or delayed diagnoses of occupational asthma (OA).

Systems constraints

There were a number of negative extrinsic influences on practice, specifically: lack of continuity of care, time pressure and increased GP workload, external targets, referral pressures, and lack of guideline use. The result has been that identifying an occupational case for asthma is a low priority for primary HCPs, who are not incentivised to do so. Some HCPs felt that lack of continuity, time and increased workload meant that they were unable to know their patients’ lives in detail as they used to, to the detriment of holistic care. MacKinnon et al25 suggested that lack of systematic screening for OA in primary care contributes to delayed diagnosis, although acknowledged that the optimal screening tool is currently unknown. Others have previously cited time constraints and lack of access to specialists as barriers to diagnosis.17 18


Although specific guidelines are published relating to identification and referral of suspected OA,6 11 there are limitations to the current model for primary asthma care that inhibit recognition and onward referral to a specialist. Additionally, lack of provision of formal education at each stage of training and variation in clinical experience are likely to influence disease-specific beliefs for HCPs, and inhibit further action in at least some cases. Recommendations for education and clinical practice are considered in table 4. Whether screening individuals with asthma in primary care for OA is helpful, and the optimal tool for doing so, are both currently unknown and require evaluation.

Table 4

Recommendations for healthcare education and clinical practice

Data availability statement

Data are available upon reasonable request.

Ethics statements

Ethics approval

Formal NHS Research Ethics Committee review was not sought since the study did not involve patients. Health Research Authority approval for this study was granted on 16 July 2018 (IRAS reference number 249409).


Supplementary materials

  • Supplementary Data

    This web only file has been produced by the BMJ Publishing Group from an electronic file supplied by the author(s) and has not been edited for content.


  • Contributors GIW undertook the study design, interviews and data analysis, with CMB acting as a critical friend. Both authors wrote and edited the manuscript.

  • Funding Commercial typing costs and participant inducements were paid from the University Hospitals Birmingham NHS Foundation Trust Occupational Lung Disease Charity Fund.

  • Competing interests Participant 1 was the wife of the primary author and a GP in a city centre practice.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.