Validation issues in questionnaires for diagnosis and monitoring of gastroesophageal reflux disease in children.

Pediatric gastroesophageal reflux disease (GERD) is common in infants and children; diagnosis is often based on symptom presentation. This paper reviews psychometric characteristics and approaches to validation of currently available pediatric GERD questionnaires. Patient-reported outcomes allow disease and treatment to be characterized in meaningful ways to patients and clinicians. Outcome measures must demonstrate reliability and validity for use in practice and in clinical trials. Reliability assesses the consistency of measures, whereas validity examines whether the instrument measures what it is purported to measure. Development of questionnaires for use with children also requires consideration regarding the respondent. Measures of pediatric GERD symptoms include the GERQ, GERQ-R, and GSQ. These measures have advantages and disadvantages with regard to feasibility, reliability, and validity. Questionnaires are lacking for children older than 4 years.