In Andalusia, the right to maximum waiting times for healthcare clashes with the available supply, leading to an increase in demand in the form of waiting lists. To address this situation, the activity of private centers has been created for certain diagnostic tests. The Social Return on Investment (SROI) model evaluates an intervention from an economic and stakeholder perspective. However, there are no studies on the suitability of waiting lists using SROI, which is why it is intended to be studied as a decision-making tool for the clinical and healthcare management of waiting lists. This research protocol is designed to determine the quality of life gained, with the EuroQol-5D-5L questionnaire, and its social assessment, with the specific survey of the SROI method, and, thus, analyze the social return on investment and determine the suitability of the intervention (diagnostic endoscopy activity arranged in a contracted center). After the study, we will know the economic (cost in public health centers and the incremental cost of extraordinary health resources), social (quality of life with health), and environmental scenarios of the concerted activity intervention in order to adjust waiting list times
