Development and Initial Validation of the Gastric Discomfort Intolerance Scale

Disorders of gut-brain interaction (DGBI) and eating disorders frequently co-occur and share disturbances across the gut-brain axis. Growing evidence suggests that aversive reactivity to physical sensations, particularly gastric discomfort intolerance, may be a key mechanism underlying both conditions. Gastric discomfort intolerance refers to the inability or unwillingness to experience aversive gastric sensations. Despite its theoretical importance, no validated measure of gastric discomfort intolerance exists. This study aims to develop and provide initial validation of the Gastric Discomfort Intolerance Scale (GDIS). Adults (n = 219) completed the GDIS and measures of convergent and discriminant validity. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) supported a unidimensional 17-item measure with excellent internal consistency (α = 0.93) and acceptable-to-excellent model fit indices (RMSEA = 0.10, 90% CI [0.08, 0.12]; CFI = 0.97, TLI = 0.96). The GDIS demonstrated convergent validity through significant positive correlations with anxiety sensitivity, depression, anxiety, stress, and some measures of interoception (Trusting). Additionally, discriminant validity was supported by non-significant associations with self-esteem and other measures of interoception (Attention Regulation, Emotional Awareness, Self-Regulation, Body Listening). Participants reporting current eating disorders had significantly higher GDIS scores than those with previous or no eating disorder history (p = 0.02). The GDIS is the first validated measure of gastric discomfort intolerance and shows excellent psychometric properties. This tool may facilitate research of gastric discomfort intolerance in eating disorders, DGBI, and other psychiatric conditions, potentially informing treatment approaches.