Background
Literature reports indicate that the clinical, humanistic and economic outcomes of drug-related morbidity (DRM) and mortality are potentially substantial.^1-4 Measuring and improving the quality of the health-care system is now firmly on the Government health policy agenda in the form of clinical governance,⁵ while an appreciation of the value of the systems approach to addressing "medical mishaps" has recently been brought to the fore.⁶ Reducing preventable drug-related morbidity (PDRM) could potentially improve both the safety and the quality of health-care whilst reducing costs. An American research programme, embedded in the systems approach, has defined PDRM and produced operational definitions of this term in the form of clinically specific indicators.⁷ These definitions were developed from a literature review and a consensus panel of geriatric medicine "experts". As in the research area of the appropriateness of prescribing,⁸ direct transcription of transatlantic findings is not necessarily valid. This paper will describe, with reference to indicator examples, the methodological process which is being undertaken to validate the US indicators for application in the UK health-care system.

Method
A preliminary validation of the 57 indicators was undertaken within the School of Pharmacy. Their face validity was assessed by three experienced clinical pharmacists and their content validity determined by cross-checking against the current British National Formulary recommendations. A two round Delphi questionnaire survey was then conducted with a sample comprising a total of 16 general practitioner (GP) primary care group prescribing leads (n=6) and primary care pharmacists working in GP practices (n=10). This process was used to formally assess the face and content validity of the indicators, develop consensus and identify additional indicators of specific relevance in the UK.

Results
Twenty of the original indicators were deleted during the preliminary validation stage due to their lack of relevance to UK primary care prescribing. In addition, two indicators required a substantial modification of wording to reflect UK clinical practice. A further four indicators, deliberately designed to not reflect PDRM, were included as a gauge of reliability. The Delphi panel generated a further 16 new indicators in the first round. At the end of the second round the pre-defined level of consensus was reached in 29 cases (19 of the US generated indicators; 10 generated by the panel in the first round). All four reliability indicators were rejected by the panel as PDRMs.

Discussion
The overall Delphi results highlighted some interesting differences in both the clinical perspective and possible philosophical viewpoints of health professionals practising in the UK and US health-care systems. The indicators derived in the US have provided a starting point for this UK work. It is, however, important to note that the work completed to date does not signify the end of the validation process. Future work, embracing the systems approach, located in both primary and secondary care is now in progress to operationalise them. This process will form a key part of refining, and hence further validation, of the indicators.

References

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