Send letter to journal:
Re: authors response to e-letters

We thank Dr Preece for his comments. We believe that he is justified in questioning the make up of the panel and that this has a significant bias for tertiary assessment of occupational lung disease. However our aim in performing this process was to get this group of experts to agree on "definitions” with a view to unifying the label at this later clinical stage of the process. In addition we hoped that the requirements of a specialist occupational lung disease assessment service would form a basis for developing a standards of care document for those giving expert medical advice in this specialist field. We felt that it was appropriate to carry out the process from this stand-point, as if this body could not agree on what constitutes occupational asthma or work aggravated asthma in principal, how could we work towards an agreed process for evaluation at all levels?

A similar exercise done in parallel using occupational physicians would be a very interesting and valuable exercise. It is likely that the view of work place based physicians will be different because of local variations in perspectives. We reiterate that it was never intended for this to be within the scope of this project. In carrying out the process in this way we certainly did not wish to alienate our occupational physician colleagues and in no way intend to imply that their viewpoint is not valued. We felt it was valuable to share the perspectives from the specialist occupational lung physician, in publishing our findings.

Finally we note the comment regarding the evidence based guidelines and whilst there is some practical relevance of the consensus to the guidelines and joint interested parties on the two documents, it was not practical to include the consensus in the guidelines. Doing so would have caused a significant delay in publishing the guidelines which was not merited as after all consensus is the least important and lowest level of evidence base.

We thank Dr Kalman for his views and understand his issues with regard to context, a point similar to that made by Dr Preece. We performed this study, specifically to deal with producing the definition on which specialist centres should base their assessment of cases of possible work related asthma. The facilities required component was specifically aimed at identifying standards of care for this process. Whilst the definitions are of relevance to the work site and legal situations, we felt that a firm basis for discussion and minimum criteria required to assess difficult cases appropriately was an important issue and the sole basis for this study. The requirement of a breech of statutory duty of care does not affect the clinical diagnosis or management of a worker in the workplace. We feel that a medical diagnosis (such as occupational asthma) should be based on what is wrong with the patient and what is the cause.

Send letter to journal:
Re: Definition of Occupational Asthma

Sir Francis and her colleagues have completed an interesting and useful piece of work in relation to a definition of, and diagnostic resources required for occupational asthma. It is, in my view, however important to identify, in full, the context of such definitions if they are not to be used for unintended purposes or, perhaps, inappropriately. Is it possible to suggest that the term 'occupational asthma' used in terms of identifying work factors important to be controlled in that individual's protection could be different from a definition of occupational asthma in terms of regulatory or litigation issues where, perhaps, part of the definition could be in relation to a breech of a statutory duty of care? I, at least, do not believe that these 2 issues are the same in relation to asthma, and in relation to a number of other health conditions which have some work relation. I wonder if the authors would agree that the deliberations in terms of scope might have been different if their starting definition had included considerations of employers' liability, as well as a clinical basis? Chris Kalman

Send letter to journal:
Re: Occupational medicine and asthma

Sir

The article by Francis et al is interesting and makes an important contribution to clinical practice. It is a pity, however, that a consensus on definition did not precede the production of evidence based guidelines (1) to make sure that the relevance of the evidence was consistent with the emerging consensus.

I note that the consensus panel comprised a group of experts in occupational respiratory diseases based in major hospitals. As far as I can tell only two of the panel are accredited specialists in occupational medicine. Whilst the individual credentials of the panel member are impeccable, full particpation by practising occupational physicians rooted in the workplaces where exposure occurs would have given better balance to the panel as a whole.

I am left wondering if the absence of practising occupational physicians is an unfortunate oversight, a reflection of how uncommon occupational asthma is in the everyday practice of occupational medicine, or a tendency by doctors to focus our attention on the most serious presentations of respiratory and other dieseases.

1. P J Nicholson, P Cullinan, A J Newman Taylor, P S Burge C Boyle Evidence based guidelines for the prevention, identification, and management of occupational asthma Occup Environ Med 2005; 62: 290-9