Characteristics of Drug Intervention Clinical Trials and Scientific Impact of the Trial Outcome: A Bibliometric Analysis Using the Relative Citation Ratio in Non-small Cell Lung Cancer from 2007 to 2016

Background Although a large number of clinical trials have been conducted, the types of clinical trials that are scientifically influential, frequently utilized by society, and contribute to the progress of evidence-based medicine (EBM) have not been studied. Thus, we aimed to investigate the relationship between the characteristics of clinical trials and the scientific impact of the outcome in non-small cell lung cancer (NSCLC) by performing a bibliometric analysis using relative citation ratio (RCR), a newly developed bibliometric index by the National Institutes of Health (NIH). Methods Primary publications of drug intervention clinical trials for NSCLC between 2007 and 2016 were included in the study. The characteristics of clinical trials were compared among four RCR categories with 50 trials in each [LOW50, 50 NIH percentile (50NIH%ile), 95 NIH percentile (95NIH%ile), and TOP50], totaling to 200 trials. Results Median RCRs of LOW50, 50NIH%ile, 95NIH%ile, and TOP50 were 0.03, 1.00, 5.76, and 26.89, respectively. Publications of Phase 3, randomized, blinded, for-profit-company supported/sponsored, multi-center trials, and trials with a larger number of subjects were shown to have a higher scientific impact. Publications of clinical trials of newly developed molecular target drugs, including epidermal growth factor receptor-tyrosine kinase inhibitors, anaplastic lymphoma kinase inhibitors, and immune checkpoint inhibitors demonstrated a higher scientific impact than those of traditional chemotherapies. Conclusion Clinical trials designed to have a high evidence level would improve the scientific impact of the outcome, and novel interventions would be another factor to improve the clinical trials' influence.