SMART PK/PD clinical trials is a cross-functional, multi-year innovation project aimed at enriching our clinical trial datasets and enabling more rapid and informed clinical decisions with a focus on patient centric designs, including SMART sampling techniques such as Finger-stick Dried Blood Spot (DBS). Various studies were designed to build capabilities (operational and technical feasibility) in SMART PK/PD technologies and were optimally intended to assess and identify devices/techniques/capture systems for use in subsequent clinical trials. In an attempt to find the appropriate model for the prediction, we applied a training-test approach from multiple SMART PK/PD clinical trials to characterize the relationship between concentrations from DBS samples versus those from the more common plasma samples taken from the clinical paradigm. We estimated the Concordance Correlation Coefficient (CCC) to assess the agreement of drug concentration measured from DBS versus that predicted from plasma via with or without intercepts linear models in the test dataset. Appropriate modeling of these relationships obtained will be chosen based on the simulated data and compared against the actual.