The study, titled "Urinary stone prevention with hydration: a randomized clinical trial of an adherence intervention," investigated a behavioral intervention program to promote fluid intake. The program was aimed at secondary prevention of urinary stones. During the 2-year follow-up period, there was no reduction in recurrent stone events compared with guideline-based standard care. However, the intervention program slightly increased the urine volume of the patients. The study was a randomized clinical trial. The main finding is the failure to prevent relapses, despite the positive effect on hydration.