Conducting randomised controlled trials in primary care: lessons from an obesity management trial

A UK trial ending in 2002 reported that a training intervention to improve the management of obesity in primary care had no impact. Process analysis showed that the intervention was taken up by very few of the practitioners in the participating practices.

The aim of the current study was to explore both the reasons behind low levels of implementation and the context in which the trial was delivered.

In-depth qualitative interviews.

General practices in the North East of England.

Interviews with 13 practitioners (GPs and practice nurses) and 10 patients, representing seven of the eight intervention practices in the largest centre of the original trial.

While patients were clear that they had participated in a trial few of those interviewed had any recollection of the intervention. Most staff were positive about the training, resources to use with patients and the weight management model, but not all training needs were met. High initial expectations of the trial gave way to disillusionment, exacerbated by significant misunderstanding by some practice staff of their role in implementation.

Frustration among practitioners managing obesity in primary care combined with unrealistic expectations of and misunderstanding about an intervention designed to improve care in the field, appeared to have resulted in disillusionment with and consequent disengagement from the trial.