The 3D study: Improving whole person care

People who have more than one chronic health condition, such as asthma, diabetes or heart disease, are said to have ‘multimorbidity’. One in four people in the UK and the USA have multimorbidity. In people over 65, this increases to two-thirds.


People with multimorbidity are more likely to experience poor physical and mental health, and a poor quality of life.

Treatment for multimorbidity places another burden on patients, who may have to take lots of different drugs, make lifestyle changes and attend numerous healthcare appointments.

Their care is often focused on each of their health conditions in isolation, rather than being patient-centred and tailored to their individual needs.

About the study

The 3D study was the largest ever trial of an intervention to improve care for people with multimorbidity, involving 1,546 patients. It was a randomised control trial, the best test of any medical intervention.

The trial evaluated a patient-centred intervention, the 3D approach, to improve how GP practices manage and care for patients with multimorbidity.

About the 3D approach

The 3D approach encourages clinicians to think broadly about the different dimensions of health, simplify drug treatment and consider mental as well as physical health.

It was designed to treat the whole person and overcome the disadvantages of treating individual conditions in isolation.

You can watch Professor Chris Salisbury, who led the 3D study, describe the approach and the research study in two videos.

What the study found

The main findings of the 3D study were published in the Lancet in July 2018.

The study showed that by making health reviews more patient-centred, patients offered the 3D approach experienced higher quality care.

However, patients’ health-related quality of life, which included measures of mobility, self-care, pain and discomfort, anxiety and depression, did not improve.

These findings provide the best evidence to date of the effectiveness of a person-centred approach for multimorbidity, for which there is international consensus but little evidence.

They also challenge the thinking on which UK and international guidelines are based.

A list of all publications from the study is available here. A full report will be published in late 2018.





The project is funded by the National Institute for Health Research (NIHR), Health services and Delivery Research Programme.

3D study logo


Professor Chris Salisbury
Centre for Academic Primary Care
Population Health Sciences
Bristol Medical School
University of Bristol
Canynge Hall
39 Whatley Road
Bristol BS8 2PS 

Tel: 0117 3314530 

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