Urbach DR et al. (2005) A measure of disease-specific health-related quality of life for achalasia. Am J Gastroenterol 100: 1668–1676

The optimal management of achalasia is controversial and there is a paucity of high-quality evidence from randomized trials comparing the effectiveness of different treatments and interventions. The absence of a valid and reliable measure of outcome is a particular problem: given that achalasia is not curable, improvements in symptoms and quality of life are the main goals of therapy and, therefore, a measure quantifying disease-specific quality of life is required.

Urbach and colleagues aimed to develop a measure of disease-specific quality of life with interval-level properties that could be applied in clinical trials. A list of 37 potential items for inclusion was derived from interviews with seven achalasia sufferers and expert opinion. Responses to a questionnaire sent to 70 individuals with achalasia were used to reduce the number of items to 10. Items ultimately selected for inclusion covered aspects of food tolerance, dysphagia-related behavior modifications, pain, heartburn, distress, lifestyle limitation and satisfaction. The measure was then recalibrated on to a 0–100 interval-level scale, where higher values indicate greater disease severity. Tests showed that the measure was reliable, had a wide effective measurement range and showed evidence of validity.

Although further work is needed to evaluate the reliability of the scale in different populations and to determine what constitutes a clinically meaningful change in scores, this scale appears to be suitable for use as an outcome measure in clinical trials and other evaluative studies of achalasia treatments.