Cancer inequalities endure despite NHS reforms
Menée en Angleterre à partir de données portant sur plus de 3,5 millions de patients atteints d'un cancer diagnostiqué entre 1996 et 2013 (24 types de cancers primitifs les plus courants ; âge : 15-99 ans), cette étude analyse l'impact des politiques de lutte contre le cancer sur l'amélioration de la survie et sur la réduction des inégalités socioéconomiques dans la survie
Real progress requires a more comprehensive approach
Much of the success of modern medicine has been built on the fundamentals of scientific method—observation, hypothesis generation, intervention, measurement, and comparison. Evidence is expected before implementation. This disciplined, assiduous, and deliberate approach led to many of the most important medical advances in the past 400 years. Do the same standards apply to public policy, arguably the biggest intervention of all?
In this issue, Exarchakou and colleagues (doi:10.1136/bmj.k764) evaluated whether the NHS Cancer Plan (2000) and associated reforms had any impact on cancer survival, and whether any gains were evenly distributed across the English population.1 Dishearteningly, they conclude that the policy has had little impact on rate of improvement in survival, or on socioeconomic disparities in survival. Does this mean the NHS cancer reforms failed?
The authors’ attempt to evaluate the impact of the reforms in a rigorous manner is laudable. Such efforts are fraught with difficulty—there are multiple variables and interventions, and advances in individual cancer types accrue gains at different rates. Accordingly, it is difficult to establish cause and effect.
Minor methodological problems could be discussed, such as the choice of measure of inequality and selection of one year survival as an endpoint. The authors use change in an absolute measure of survival to evaluate the impact of policy on inequities. Patterns in trends can differ depending on whether the metric used is survival or excess mortality, and whether an absolute or relative measure is used.2 None is considered an ideal method, but the conclusions might have differed if another metric was used.
The authors also only used a comparison between the highest and lowest socioeconomic groups, and it would be useful to understand more about patterns among those in between. The authors were, through necessity, limited to an area level measure of deprivation; again results might be affected by the choice of measure.3 It seems unlikely, however, that the general conclusions would have differed substantially, regardless of these methodological subtleties.
The policies implemented to tackle cancer related inequity in the United Kingdom were largely focused on two key areas. Firstly, activities to reduce the incidence of cancer (such as tobacco control initiatives). If implemented in a way that impacted most on people in lower socioeconomic groups, these could have pro-equity effects on cancer mortality. However, reducing cancer incidence is not detected by measuring changes in survival among those with a diagnosis, which was the focus of this study.
The second set of strategies aimed to reduce waiting times for treatment to end the “postcode lottery.” These strategies were largely focused on patient behaviours, based on the idea that patients in higher deprivation areas tended to have less knowledge about cancer and its symptoms and delayed seeking care. As highlighted by Exarchakou and colleagues, there is little or no evidence that such policies impact cancer outcomes or reduce inequities. (...)
BMJ , éditorial en libre accès, 2017