The Swedish reflux trial in children: I. Study design and study population characteristics.

PURPOSE: We compared the rates of febrile urinary tract infection, kidney damage and reflux resolution in children with vesicoureteral reflux treated in 3 ways, including antibiotic prophylaxis, endoscopic therapy and surveillance with antibiotics only for symptomatic urinary tract infection. MATERIALS AND METHODS: Children 1 to younger than 2 years with grade III-IV reflux were recruited into this prospective, open, randomized, controlled, multicenter study and followed for 2 years after randomization. The main study end points were recurrent febrile urinary tract infection, renal status on dimercapto-succinic acid scintigraphy and reflux status. Outcomes were analyzed by the intent to treat principle. RESULTS: During a 6-year period 128 girls and 75 boys entered the study. In 96% of cases reflux was detected after urinary tract infection. The randomization procedure was successful and resulted in 3 groups matched for relevant factors. Recruitment was slower than anticipated but after patients were entered adherence to the protocol was good. Of the children 93% were followed for the intended 2 years without a treatment arm change. All except 2 patients completed 2-year followup scintigraphy. CONCLUSIONS: Recruitment was difficult but a substantial number of children were entered and randomly assigned to 3 groups with similar basic characteristics. Good adherence to the protocol made it possible to address the central study questions.