Greenwich asthma study

Journal article

Editor—Premaratne et al amassed an impressive amount of data in the Greenwich asthma study,1 but their outcome measures were unlikely to be able to detect an effect of their intervention. We think that they may have had an unreal expectation of the impact of the intervention in primary care, perhaps reflecting the absence of primary care researchers in the study team. Designing large scale studies to test guidelines and educational interventions is not easy, particularly in inner city general practice.2 When testing whether nurses improve the care of patients with asthma in general practice, appropriate primary outcomes are measures of asthma control and health service use in the patients who consulted with the nurses rather than in the wider population of asthmatic patients. To judge the efficacy of the study nurses on their lack of effect on patients they did not see seems harsh, although asking asthmatic patients to attend review sessions is arguably part of their role. Though the mean square root of quality of life of the total asthmatic population is clearly an important (secondary) outcome, its importance may be obscure to many readers. Even the chosen secondary outcomes (steroid prescribing, attendance at accident and emergency departments, hospital admission) did not use as a denominator the patients who consulted during the study; neither is it clear that the study was sufficiently powered to detect differences for these variables. Focusing on the questionnaires or clinical records of these patients or a predetermined high risk group would have elucidated better the efficacy of the intervention. Most studies showing the efficacy of education and guided self management have been carried out in hospital or outpatient populations—that is, among those with more severe disease. An intervention judged on its efficacy among all asthmatic patients registered in general practice, even those not receiving drug treatment, might be expected not to show a benefit. Intervention by a practice nurse is not necessarily appropriate for all asthmatic patients. Few data are presented about the delivery of a complex health service intervention. For instance, interactive educational methods may be more effective than simple information transfer when implementing asthma guidelines.3 A qualitative analysis unpicking the black box of this educational programme would have been instructive.4 Without this it may be too early to suggest, as the authors do, that doctors might be more effective than nurses in educating patients with asthma. Should the results of the study influence government policy? To conclude that primary care nurses trained by hospital specialist nurses are ineffective would be premature until other studies with more focused outcome assessment and cost effectiveness data have been reported.

Authors: Feder, G; Griffiths, C; Foster, G; Ahmed, S; Maclaren, D

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: BMJ Publishing Group
• Journal: British Medical Journal
• Volume: 320
• Issue: 7234
• Pages: 580-580
• Publication date: 2000-02-26
• DOI: 10.1136/bmj.320.7234.580
• EISSN: 0959-8138
• ISSN: 1759-2151
• Language: English
• Keywords: Intervention (counseling); Attendance; Nursing; Asthma; Emergency department; Population; Nice; Greenwich; Psychological intervention; Medicine; Test (biology); Family medicine