The measurement of inequities in health: lessons from the British experience.

There has been an acrimonious debate about trends in inequality in health in the U.K. over the last couple of years. Whilst the acrimony is highly specific to the U.K. context, the terms of the debate contain general lessons for others who would venture into the same territory. This paper has focused on problems with using occupational classifications, with using groups of different size, with assessing trends in inequalities in death, with the measurement tool employed, with comparing patterns of ill-health and with the framework of explanation. The U.K. debate provides a good example of the first problem. Much of the debate has had to rely on the classification of occupation at the time of death by the Registrar General's Department. The scheme used was devised in 1911 and has persisted despite the massive changes in occupational structure since then. The groups now contain different occupational titles, and it is not at all clear what is being referred to by the RG scheme. Moreover, the balance of the RG groups has shifted dramatically. Any scheme applied regularly and routinely to mortality statistics over time will have these problems--it is not surprising that it is very difficult to interpret patterns of class death rates. The argument over trends in the U.K. has sometimes focused exclusively on the measurement tool--the standardized mortality ratios. Various alternatives have been proposed, in particular the Gini coefficient which clearly answers a different, possibly rather uninteresting, question. The correct way of comparing 'top' and 'bottom' is to devise a method which produces a group of constant size in the different communities or at different times. The focus on death rather than survivorship is queried as is the usual restriction to comparing rates of early death. Possibilities of comparing patterns of ill-health are examined in the fifth section. Whilst routine health care data or survey morbidity data are invaluable, it seems highly unlikely that they can be compared between communities or over time. The alternative is to develop a series of 'risk' indicators and these are discussed in Section 5.3. The examination of patterns of inequalities in death and ill-health highlights the complexity of discussing aetiology. We consider the balance between long-term and short-term effects and the possible role of (ill)-health on the social mobility process, and problems of directly relating low income to poor health.