Transform Incoming Lab Data into SDTM LB Domain with Confidence
Anthony L. Feliu · 2012
Converting incoming lab data into a submission–ready format is often challenging and stressful to the programmer. Vendors, sponsors, and collection instruments all have their own structures and nomenclature for lab data. This paper details a process to mold disparate data into a unified whole. In brief, verbatim values of each incoming data file will be mapped one-to-one into SDTM variables. Mapped data are then compared to a dictionary of tests which is held outside the program as the “gold standard.” When a match is found, verbatim values are updated to CDISC-compliant dictionary terminology. Otherwise the record is flagged for review. Next, result values for quantitative tests are compared to the “preferred units” for that test. The incoming result will either be accepted, rescaled with help from a second dictionary of conversion factors, or flagged. Similarly, qualitative test results are standardized. Moving terminology out of program code into external dictionaries provides excellent transparency and traceability. The approach is readily implemented. Both program code and dictionaries are maintainable and extensible across protocols or product lines.