Intended for healthcare professionals

General Practice

Randomised controlled trials in primary care: case study

BMJ 2000; 321 doi: (Published 01 July 2000) Cite this as: BMJ 2000;321:24
  1. Sue Wilson, senior research fellow (,
  2. Brendan C Delaney, senior lecturer,
  3. Andrea Roalfe, medical statistician,
  4. Lesley Roberts, research associate,
  5. Val Redman, project officer,
  6. Andy M Wearn, lecturer,
  7. F D Richard Hobbs, professor of primary care and general practice
  1. Department of Primary Care and General Practice, Division of Primary Care, Public and Occupational Health, University of Birmingham, Medical School, Birmingham B15 2TT
  1. Correspondence to: S Wilson
  • Accepted 25 April 2000

Editorial by Thomas

Although over 90% of patient contacts within the NHS occur in primary care, many of the interventions used in this setting remain unproved.1 The relevance of research undertaken in secondary or tertiary care to general practice is questionable, and more research based in primary care is needed.2 Increasing research in primary care will inevitably increase demand for randomised controlled trials in this setting. Some of the trials will be of health service interventions (pragmatic trials),3 where the focus lies in assessing the cost effectiveness of an intervention rather than efficacy or safety. The difficulties experienced in doing randomised controlled trials in primary care have been reported46 and are not restricted to this setting. 7 8 We discuss some of the issues that must be considered when conducting and interpreting the results of trials in primary care using examples generated during a trial of the management of dyspepsia (box).

Birmingham open access endoscopy study

The study aimed to evaluate the effectiveness of two management strategies for patients presenting in primary care with symptoms of dyspepsia. Two randomised controlled trials were conducted concurrently, with eligibility being determined by the patient's age at presentation. Randomisation was done at the individual patient level by using sealed opaque, sequentially numbered envelopes during a primary care consultation for dyspepsia.

Initial endoscopy trial

Eligible patients—50 years of age or older.

Intervention—Referred for open access endoscopy.

Test and endoscopy trial

Eligible patients—Under 50 years.

Intervention—Tested for Helicobacter pylori antibodies with Helisal near patient test. Patients with positive results referred for open access endoscopy; those with negative results received symptomatic treatment only.

Control arms (both trials)—Managed according to “usual practice” excluding open access endoscopy. This included antacids, H2 receptor antagonists, proton pump inhibitors, outpatient gastroenterology referral, facilitated or direct access endoscopy (for example, vetted by consultant), …

View Full Text