Exploring the pathology of quality failings: measuring quality is not the problem – changing it is †

The USA can boast a long history of investigation into quality failings in health care. From Ernest Codman and Abraham Flexner in the opening decades of this century through to the intense activity of the 1980s and 1990s, much careful study has exposed extraordinary and at times scandalous deficiencies in the quality of care (Millenson 1997; Chassin & Galvin 1998; Schuster et al. 1998). Yet we are still far from developing ‘industrial strength’ quality in health care: in all but a few isolated areas, such as general anaesthesia, ‘six sigma quality’ (i.e. a handful of errors per million) seems wishful thinking (Chassin 1998). Pockets of excellence and innovation notwithstanding, the dominant experience of the past two decades has been an increasing ability to document quality failings and a seeming inability to mobilize effective action (Coye & Detmer 1998). The rich literature on health‐care quality that has sprung up over the past few decades has largely failed to provide a clear direction for quality improvement activity. This paper analyses some of the reasons why this might be so. Contrasting the relative absence of progress on health‐care quality with the relative success of disease epidemiology provides some illuminating parallels. In essence, study of the quality of care has focused largely on providing a ‘descriptive epidemiology’. Much more work is needed yet to unravel the underlying pathology of quality failings, in order to empower development of an ‘aetiological epidemiology’ of quality in health care. Such understanding is essential as a precursor to targeted and effective preventative and remedial action.