Deficiencies in the transfer and availability of clinical trials evidence: a review of existing systems and standards.

BACKGROUND: Decisions concerning drug safety and efficacy are generally based on pivotal evidence provided by clinical trials. Unfortunately, finding the relevant clinical trials is difficult and their results are only available in text-based reports. Systematic reviews aim to provide a comprehensive overview of the evidence in a specific area, but may not provide the data required for decision making. METHODS: We review and analyze the existing information systems and standards for aggregate level clinical trials information from the perspective of systematic review and evidence-based decision making. RESULTS: The technology currently used has major shortcomings, which cause deficiencies in the transfer, traceability and availability of clinical trials information. Specifically, data available to decision makers is insufficiently structured, and consequently the decisions cannot be properly traced back to the underlying evidence. Regulatory submission, trial publication, trial registration, and systematic review produce unstructured datasets that are insufficient for supporting evidence-based decision making. CONCLUSIONS: The current situation is a hindrance to policy decision makers as it prevents fully transparent decision making and the development of more advanced decision support systems. Addressing the identified deficiencies would enable more efficient, informed, and transparent evidence-based medical decision making.

Capecitabine, 5-fluorouracil and S-1 based regimens for previously untreated advanced oesophagogastric cancer: A network meta-analysis.

As evidence is inconsistent and based on either isolated Asian or Western studies, we conducted a network meta-analysis (NMA) to examine efficacy and safety of 5-FU (5-fluorouracil), capecitabine and S-1-based first-line treatment of advanced esophagogastric cancer in Asian and Western patients. Medline, EMBASE, CENTRAL and conferences ASCO and ESMO were searched up to January 2016 for randomized-controlled-trials comparing 5-FU, capecitabine or S-1-based regimens with equal chemotherapy backbones. Direct and indirect data for overall survival (OS) and progression-free-survival (PFS) were combined on the Hazard Ratio (HR)-scale using random-effects NMA and calculated as combined HRs and 95%credible intervals (95%CrI). Grade 1-2 and grade 3-4 adverse events were compared with pair-wise meta-analysis. Fifteen studies were identified including capecitabine (n = 945), 5-FU (n = 2,132) or S-1 (n = 1,636). No differences were found in respectively OS and PFS for capecitabine-based versus 5-FU-based regimens (HR = 0.89, 95%CrI = 0.76-1.04 and HR = 0.98, 95%CrI = 0.75-1.32), S-1-based versus 5-FU-based regimens (HR = 0.92, 95%CrI = 0.82-1.04 and HR = 0.88, 95%CrI = 0.70-1.11) and S-1-based versus capecitabine-based regimens (HR = 1.03, 95%CrI = 0.87-1.22 and HR = 0.89, 95%CrI = 0.65-1.20). Effects were similar in Asian and Western subgroups. Toxicity profiles were different but a lower frequency of relevant adverse events was observed with S-1 In conclusion, as efficacy was similar, choosing fluoropyrimidines should be based on their individual toxicity profiles.