Gastrointestinal Health Questionnaire for Rett Syndrome: Tool Development

PURPOSE:We report the development and validation of a tool to assess gastrointestinal health in Rett syndrome (RTT). We hypothesized that the Gastrointestinal Health Questionnaire (GHQ) is a valid clinical outcomes measure of gastrointestinal health in RTT. METHODS:We used parent interviews, surveys, and literature review to generate a questionnaire related to gastrointestinal health and function, mood and behaviors, and parental concerns for individuals with RTT. Parents of affected and unaffected individuals provided responses to the GHQ, assessed the relevance and importance of statements, and completed five surveys related to gastrointestinal health, child-related mood and behaviors, and parent concerns. We used multivariate item analysis, two-sample t-tests, and correlations to assess the validity of the GHQ. RESULTS:We documented acceptable internal consistency of statements related to gastrointestinal health and function (Cronbach-α = 0.91), RTT-related mood and behaviors (Cronbach-α = 0.89), and parent concerns (Cronbach-α = 0.95) in the GHQ. We documented favorable external validity, based on differences in response scores between parents of affected and unaffected individuals (p