Several randomised trials have established that disease management programmes offering, for example, home visits, heart failure clinics, and telephone interventions result in better adherence to treatment and reduced admissions to hospital for heart failure than standard care for people with heart failure.1 2 3 4 Current evidence is unclear, however, on the impact of such programmes on mortality, all cause admissions, quality of life, and cost reduction. The most effective components of the interventions and the benefits to different subgroups are also unknown. Moreover, such evidence comes from small trials with short follow-up, performed at single centres, that applied complex strategies to selected high risk populations. These characteristics might affect both the internal and external validity of the trials' findings. In this week's BMJ, Clark and colleagues present a …