Analysis of data query as parameter of quality

Data query (DQ) rate per case record form (CRF) page is an index of quality of clinical trial data, which can be affected by the phase of clinical trial, the therapeutic area, and the country, where investigator site is located.

To compare DQ rate per page by countries, phases, and therapeutic areas.

Data from 19 paper CRF clinical trials conducted at 352 sites, in 5,610 patients were entered into clinical data management system by double data entry method, and DQs were generated. The DQ rate per page was compared for the phase, therapeutic area, and the country, by parametric analysis of variance (ANOVA) and nonparametric test-Kruskal-Wallis and median test. Multiple comparisons test was conducted for each category using Tukey's Studentized Range Test.

The total number of DQs from 108,599 CRF pages was 33,177 (0.306/CRF page). The studies included 12 countries, all phases, and seven therapeutic areas. Comparison of DQ rate per page showed a significant difference between phases, countries, and therapeutic areas. However, multiple comparisons showed that the DQ rate per page was significantly different between Phase I and other phases, and oncology, cardiology, endocrinology, and dermatology. The DQ categories were: Missing 21.8%, confirmatory 50.1%, and clarification 28.2%. The most common DQs by CRF field were: Lab data (23.2%), physical examination (17.4%), study assessment (17.4), and concomitant medication (12%). There was no correlation between the number of CRF pages and DQ rate per page per study.

The phase of study and therapeutic area could impact the data quality as measured by DQ rates.