Variations in Definitions and Outcome Measures in Gastroesophageal Reflux Disease: A Systematic Review.

CONTEXT: Gastroesophageal reflux (GER) is defined as GER disease (GERD) when it leads to troublesome symptoms and/or complications. We hypothesized that definitions and outcome measures in randomized controlled trials (RCTs) on pediatric GERD would be heterogeneous.

OBJECTIVES

Systematically assess definitions and outcome measures in RCTs in this population.

DATA SOURCES: Data were obtained through Cochrane, Embase, Medline, and Pubmed databases.

STUDY SELECTION: We selected English-written therapeutic RCTs concerning GERD in children 0 to 18 years old.

DATA EXTRACTION: Data were tabulated and presented descriptively. Each individual parameter or set of parameters with unique criteria for interpretation was considered a single definition for GER(D). Quality was assessed by using the Delphi score.

RESULTS

A total of 2410 unique articles were found; 46 articles were included. Twenty-six (57%) studies defined GER by using 25 different definitions and investigated 25 different interventions. GERD was defined in 21 (46%) studies, all using a unique definition and investigating a total of 23 interventions. Respectively 87 and 61 different primary outcome measures were reported by the studies in GER and GERD. Eight (17%) studies did not report on side effects. Of the remaining 38 (83%) studies that did report on side effects, 18 (47%) included this as predefined outcome measure of which 4 (22%) as a primary outcome measure. Sixteen studies (35%) were of good methodological quality.

LIMITATIONS: Only English-written studies were included.

CONCLUSIONS

Inconsistency and heterogeneity exist in definitions and outcome measures used in RCTs on pediatric GER and GERD; therefore, we recommend the development of a core outcome set.