ArticlesEffect of enhanced feedback and brief educational reminder messages on laboratory test requesting in primary care: a cluster randomised trial
Introduction
Laboratory services play an important part in screening, diagnosis, and management of patients within primary care. Use of laboratory tests has increased substantially in recent years,1, 2 and a survey of UK laboratories showed an 83% increase in requests for tests from primary care between 2000 and 2004.3
There are many potential reasons for this rise, including the development of new useful tests and the effect of new guidelines and contracts.4, 5 However, evidence suggests that unnecessary ordering of tests could be a component of this increase.6, 7, 8 Unnecessary test requesting is not only a burden on laboratory resources, but also can lead to subsequent unnecessary investigation and treatment of healthy individuals with false-positive results.9, 10, 11, 12 Furthermore, unnecessary requests are an inappropriate use of the finite resources available for health-care provision as a whole.1
The effectiveness of strategies to change the practice of health professionals in general, and test requesting in particular, has varied.1, 13, 14, 15, 16, 17, 18 Reviews have suggested that audit and feedback of test ordering rates, educational messages, test request form changes, reminders, and computer-decision support are all potentially effective methods of changing test ordering behaviour.10, 13, 14, 15 A systematic review13 that focused on studies evaluating methods to improve diagnostic test requesting, including 49 studies with a control group, showed that most interventions assessed were effective. However, conclusions drawn from the study are limited by methodological flaws, such as lack of a randomised comparison group in 41 of the 49 studies. Additionally, few studies assessed the effectiveness of these interventions within a primary-care setting. A systematic review19 that included 85 randomised trials showed that audit and feedback have small to moderate effects on health professionals' practice; however, the evidence for test requesting within the primary-care setting is sparse since only two of the trials studied the effect of feedback on laboratory-test requesting within primary care. The authors concluded that their review does not provide support for unevaluated use of audit and feedback. Furthermore, current systematic reviews suggest that single-intervention strategies could be as effective as multiple complex interventions in changing health-profession practice.17, 19 At the time of planning the current study, we had recently completed a cluster randomised trial of two strategies to reduce requests for lumbar spine and knee radiographs in primary care.20 We reported that although simple, comparative audit and feedback of request rates had no discernible effects, the provision of educational reminder messages led to a 20% relative reduction in requests. These interventions were judged to be relatively easy for radiology departments to implement. Here we report the results of a cluster, randomised trial, using similar interventions to those used in our previous study, to determine the effect of enhanced feedback and brief educational reminder messages on requests for laboratory tests in primary care.
Section snippets
Setting and population
The study took place in the north east of Scotland, UK, and involved all 85 primary-care practices (approximately 370 family practitioners) in the area covered by NHS Grampian. The clinical laboratories based within Aberdeen Royal Infirmary provide all laboratory services for these primary-care practices.
The sample size was based on a cluster level analysis adjusted for the test ordering patterns in the 12 months before the intervention by analysis of covariance. Data for the number of tests
Results
We planned to recruit the 90 practices within NHS Grampian; however, four of these practices merged with others before the start of the study and two practices merged with each other during the pre-intervention period. Thus 85 practices were allocated to the intervention groups and included in the trial (figure). No practices refused to take part and every practice contributed data to both 12-month pre-intervention and intervention periods. The practice characteristics were similar across the
Discussion
Our study assessed the effect of enhanced feedback and brief educational reminder messages on nine tests requested in primary care over 1 year. Enhanced feedback alone and brief educational reminder messages alone each achieved moderate19 reductions of around 10% in the number of requests in total, whereas the effect of the interventions in combination showed larger reductions of more than 20% in the total targeted tests requested. The effects of the interventions varied across the individual
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