2003 OPEN FORUM Abstracts
DEVELOPMENT OF A UNITED
KINGDOM INTER-LABORATORY QUALITY ASSURANCE SCHEME
A. J. Moore*, A. K. Butterfield**, T. P. Watts, T. Marshall MBE MSc *City Hospital - Birmingham, **Wordsley Hospital Stourbridge, Manor Hospital Walsall, University of Birmingham, United Kingdom
INTRODUCTION: Until now there has not been a nationwide inter-laboratory quality assurance scheme within the United Kingdom. However, an audit of routine respiratory function tests (dynamic and static lung volumes and transfer factor) has been conducted every 5 years within the West Midlands region of the UK since 1991. Following the third audit which was undertaken in 2001 the Association for Respiratory Technology and Physiology (ARTP), which is the professional association for those practising Respiratory Physiology in the UK, adopted the methodology of the West Midlands audit and this is now being piloted on a nationwide basis in the UK. This paper presents the methodology and results of the third West Midlands audit of all 23 adult laboratories which was undertaken during 2001, and goes on to describe how this scheme is being piloted nationwide through a network of regional groups.
METHODOLOGY: The first phase of the audit was performed by postal questionnaire and examined compliance with nationally recommended[1,2] reference value sets, units of measurement, terminology, pre-attendance advice for patients and reversibility protocols. The second phase involved three physiological controls visiting each laboratory and being tested by the hospitals own staff using their standard protocol. Forty one items of equipment were involved from five manufacturers. The following parameters were recorded : FVC, FEV1, PEF, FRC, TLC, TLCO, VA. To monitor the three subjects over the duration of the audit, measurements of dynamic lung volumes on each subject were also made at each centre using a portable spirometer; these showed no significant variability.
RESULTS: The Phase 1 results showed that there was generally poor compliance with those aspects of the BTS/ARTP guidelines covered by this survey. International differences in terminology were found to be unhelpful to laboratories and manufacturers. Pre-attendance advice to patients was not widely implemented. Guidance on measuring short acting bronchodilator response was confusing.
The Phase 2 results showed no statistically significant differences between subjects or laboratories, but significant differences between manufacturers for the following parameters :-
|p value||0.020||0.042||< 0.0005||0.001||<0.0005|
Continued improvement within laboratories since 1996 was confirmed but statistically significant manufacturer differences were highlighted that were not identified in the previous audits.
DISCUSSION: The Phase 1 results will assist future debate and production of revised guidelines. The Phase 2 methodology incorporated for the first time statistical analyses that were able to remove the dominant inter-subject variability and enabled simple inter-laboratory comparison. On this basis, the scheme is now in the process of being piloted in regions throughout the UK and the authors commend the methodology to colleagues in other localities.
1. BTS/ARTP Guidelines for the Measurement of Respiratory Function - Respiratory Medicine (1994) 88, 165-194
2. British Thoracic Society Guidelines for the Management of Chronic Obstructive Pulmonary Disease - Thorax (1997);52 (Suppl 5)