Study designs of evaluations included in the review
The included studies were open-label trials, randomised controlled trials (RCTs) and crossover RCTs.
Specific interventions included in the review
Studies that assessed a symptomatic response to a short (1 to 4 weeks) course of normal- or high-dose PPI were eligible for inclusion. The included studies used omeprazole (20 or 40 mg), lansoprazole (30 or 60 mg) or pantoprazole (40 mg). The authors' definition of response was accepted for the review. The included studies used different definitions of treatment response (further details were reported). The included studies assessed treatment response at 5 days to 4 weeks.
Reference standard test against which the new test was compared
The studies had to compare clinical response to PPI with an objective test for GERD (i.e. 24-hour monitoring and/or endoscopy, or a structured symptom scoring system). The included studies used ambulatory 24-hour pH monitoring, upper gastrointestinal endoscopy and symptom scores. An abnormal pH results was defined as a pH of less than 4.0 recorded for more than 4% of a 24-hour period. For endoscopy, abnormal was defined as at least grade I oesophagitis on a commonly used classification system. For symptom scores, the review accepted a diagnosis of GERD when the authors used predetermined clinical criteria or when the symptoms reached an adequate score for GERD. The reviewers stated that symptom scores had not been validated extensively.
Participants included in the review
Studies of adults (aged 18 years or over) with presumptive diagnosis of GERD, based on symptoms and history, were eligible for inclusion. Studies that focused on children or patients with complications caused by GERD, alarm symptoms, extraoesophageal symptoms of GERD or suspected cardiovascular disease, were excluded. The studies had to include patients regardless of their symptom characteristics. The included studies were conducted in primary care and specialist care settings, and included patients with the full spectrum of GERD severity. Most of the studies had more male than female participants, and most patients had symptoms for more than 3 months.
Outcomes assessed in the review
The inclusion criteria for the outcomes were not specified.
How were decisions on the relevance of primary studies made?
One reviewer screened studies for inclusion. The final decision on study exclusions was made by consensus with two other reviewers.