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

Pediatrics. 2017 Aug;140(2):e20164166. doi: 10.1542/peds.2016-4166.


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.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Adolescent
  • Antacids / therapeutic use
  • Child
  • Child, Preschool
  • Delphi Technique
  • Gastric Acidity Determination
  • Gastroesophageal Reflux / complications
  • Gastroesophageal Reflux / diagnosis*
  • Gastroesophageal Reflux / etiology
  • Gastroesophageal Reflux / therapy*
  • Gastroscopy
  • Humans
  • Infant
  • Infant, Newborn
  • Outcome Assessment, Health Care*
  • Randomized Controlled Trials as Topic


  • Antacids