RESUMO
Objective@#To explore the methods for generating evidence on health outcomes in children with rare diseases.@*Methods@#The data from 30 clinical trials on rare neurological diseases in children from January 2008 to December 2018 were collected and analyzed.Statistical analysis was conducted on the relationship between the study sponsor and the study center, the number of participants and the prevalence rate.@*Results@#Thirty studies involved 6 types of diseases, including 14 kinds of diseases.(1) All global multicenter studies (14 items) were initiated by pharmaceutical companies, whereas most of single-center studies (6/7 kinds, 86%) and multiple centers within one country(7/9 kinds, 78%) were initiated by investigators.There was a significant correlation between the research center and the research sponsor(P<0.001). (2) Most of the drugs studied were selected based on previous clinical trials (9/30 items) and animal experiments (9/30 items). (3) The median number of participants included 39 cases (10-215 cases), and 60%(18/30 items) of the studies was fewer than 50 cases.(4) Study design: 53%(16/30 items) of studies were randomized controlled studies, 33%(10/30 items) studies were open-label single-arm studies, and 14% (4/30 items) were randomized cross-over trials.Seventy-five percent(12/16 items)of randomized controlled studies were initiated by pharmaceutical companies, 50%(5/10 items) open-label single-arm studies and all randomized cross-over trials were initiated by investigators.There was a statistical correlation between the study sponsors and the study design method (χ2=7.602, P=0.022). (5) Outcome index: Scale score was used as the primary outcome in half of studies.Other studies used symptom improvement or pathological changes.@*Conclusions@#Clinical trials in rare diseases enrolled fewer participants than that in non-rare diseases, and the study design method was relatively simple.Therefore, it is necessary to further improve the level of evidence of clinical research of rare diseases through global and multi-center recruitment, initiation of pharmaceutical companies and improving the study design method.