The quality and content of national population-based health care surveys are enhanced through integrated designs that link additional medical, behavioral, environmental, socio-economic and financial content from multiple sectors. In this study, the content in selected Project Data Sphere (PDS) cancer patient-level phase III clinical datasets have been augmented by linking the social, economic, and health-related characteristics of like cancer survivors from nationally representative health and health care-related data from the Medical Expenditure Panel Survey. Attention is given to the identification of the segment of the target population represented by the nonprobability based clinical trial samples and restricting inferences based on the integrated data to these subdomains. Study findings include probabilistic assessments of the representation of the patients in the respective clinical trials relative to the characteristics of cancer survivors in the general population and an evaluation of the reproducibility of analytic findings. The study illustrates the enhancements achieved to the analytic capacity and utility of the PDS cancer clinical trial data through data integration.