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The SDTMIG states "When a clinical classification result is based on multiple procedures/scans/images/physical exams performed on different dates, RSDTC may be derived." Some sponsors assign or derive the date of overall response (RSDTC) associated with the disease assessment timepoint and some sponsors collect the date of overall response (RSDTC) associated with the disease assessment timepoint and provide instructions to the site/vendor on their convention on how to populate it when there is more than one evaluation date. In the RS examples, when there are multiple dates of evaluation performed as part of the disease assessment timepoint, the RSDTC is populated using the following commonly used convention (either entered by the investigator, assigned by the sponsor, or assigned by an independent assessor): For For responses of CR (Complete Response) and PR (Partial Response), the latest date associated with the evaluation is used; for responses of PD (Progressive Disease) and SD (Stable Disease), the earliest date associated with an evaluation is used. This convention is based on the following concepts: when evaluating measures of disease burden over time such as duration of response or progression free survival, it is generally considered conservative to assign a negative outcome, such as disease progression, to the date the assessment is initiated but not to assign a date to a positive response until the assessment is completed. A For SD (Stable Disease) implies no change in disease status for at least a minimum time. While the absence of progression can only be certain with a complete evaluation, the status of the first evaluations cannot be carried forward to the last evaluation date in the assessment; therefore, using the earliest date gives the most conservative approach when determining if a subject met the criteria for stable diseasedifferent conventions have been used in industry and the rationale varies. For the examples below, the convention used for SD was to assign the earliest date to RSDTC. However, picking the latest date is acceptable and a common approach. For NE (Not evaluable), a date associated with the assessment is required but it generally does not impact the analysis so either the earliest or latest date can be used.
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