Examining Methods and Practices of Source Data Verification in Canadian Critical Care Randomized Controlled Trials

Abstract

Statement of the Problem: Source data verification (SDV) is the process of comparing data collected at the source to data recorded on a Case Report Form, either paper or electronic (1) to ensure that the data are complete, accurate and verifiable. Good Clinical Practice (GCP) Guidelines are vague and lack evidence as to the degree of SDV and whether or not SDV affects study outcomes. Methods of Investigation: We performed systematic reviews to establish the published evidence-base for methods of SDV and to examine the effect of SDV on study outcomes. We then conducted a national survey of Canadian Critical Care investigators and research coordinators regarding their attitudes and beliefs regarding SDV. We followed by an audit of the completed and in-progress Randomized Controlled Trials (RCTs) of the Canadian Critical Care Trials Group (CCCTG). Results: Systematic Review of Methods of SDV: The most common reported or recommended frequency of source data verification (10/14 - 71%) was either based on level or risk, or that it be conducted early (i.e. after 1st patient enrolled). The amount of SDV recommended or reported, varied from 5-100%. Systematic Review of Impact of SDV on Study Outcomes: There was no difference in study outcomes for 1 trial and unable to assess in the other. National Survey of Critical Care Investigators and Research Coordinators: Data from the survey found that 95.8% (115/120) of respondents believed that SDV was an important part of Quality Assurance; 73.3% (88/120) felt that academic studies should do more SDV; and 62.5% (75/120) felt that there is insufficient funding available for SDV. Audit of Source Data Verification Practices in CCCTG RCTs: In the national audit of in-progress and completed CCCTG RCTs, 9/15 (60%) included a plan for SDV and 8/15 (53%) actually conducted SDV. Of the 9 completed published trials, 44% (4/9) conducted SDV. Conclusion: There is little evidence base for methods and effect of SDV on study outcomes. Based on the results of the systematic review, survey, and audit, more research is needed to support the evidence base for the methods and effect of SDV on study outcomes.