Introduction: The influence of the gut-brain axis and the prevalence of psychological comorbidities in patients with chronic gastroduodenal symptoms are widely acknowledged. Consequently, it is recommended that clinicians routinely evaluate the mental wellbeing of these patients as part of standard care. However, there is currently a lack of validated questionnaires designed specifically to assess mental wellbeing within this patient population. This research describes the multi-phase process used to develop and validate a novel mental wellbeing scale for patients with chronic gastroduodenal symptoms, the Alimetry® Gut-Brain Wellbeing (AGBW) Survey.
Methods: A patient-centred co-development process was implemented, employing a multi-phase mixed-methods approach with input from a precursory user needs interview study. In Phase 1, the most relevant concepts for this patient population were selected from existing mental health scales, utilising data from 79 patients with chronic gastroduodenal symptoms. During Phase 2, an interdisciplinary team of experts generated scale items based on the identified concepts and existing literature. In Phase 3, the scale underwent pre-testing with external gastroenterologists (n=9), health psychologists (n=3), and patients (n=12). Feedback was incorporated through multiple rounds to refine the scale. Lastly, in Phase 4, the psychometric properties of the scale were assessed in a sample of 311 patients via an anonymous online survey.
Results: The final AGBW Survey comprises a patient preface, an opt-out option, 10 close-ended questions, and an optional open-ended question. This multidimensional scale assesses general mental wellbeing, alongside specific subscales relating to depression, stress, and anxiety. The subscale and total scores demonstrated high internal consistency reliability (α= .91 for the total scale; α= .72-.86 for subscales). As shown in Table 1, the total and subscale scores also showed good convergent, divergent, and concurrent validity compared to existing questionnaires, with large effect sizes. The scale was also able to successfully discriminate between those who did or did not have a self-reported previous mental health diagnosis, showing good known groups validity.
Conclusions: The AGBW Survey is a brief, valid, and reliable scale for assessing mental wellbeing in patients with chronic gastroduodenal symptoms. It serves as a valuable tool to complement physiological tests, enabling the routine assessment of mental wellbeing in these patients. The AGBW Survey has the potential to guide psychological referrals, inform multidisciplinary management plans, and evaluate treatment outcomes in clinical and research settings.

Table 1. Pearson correlation coefficients between the AGBW Survey scores and comparative questionnaires used for validity testing