Purpose: To synthesize evidence on decisional needs assessments and patient decision aid (PtDA) trials based on the Ottawa Decision Support Framework (ODSF) in order to validate the concepts and test the main assertion in the ODSF. Decisional Needs: The systematic review studies (n=45) validated all of the decisional needs identified in the ODSF. Nine new manifestations of ODSF decisional needs emerged (e.g. information overload, unreceptive to information/deliberation, relationship barriers with practitioner). PtDAs: The sub-analysis identified 24 ODSF PtDA trials. Compared to usual care, ODSF PtDAs improved decision quality, addressed decisional needs and reduced decision delay. Further evaluation is needed on downstream impacts of these improvements on decision-making. Conclusions: Using Walker and Avant’s theory testing steps, the integrated findings from the systematic review and sub-analysis validated the ODSF decisional needs concepts and tested the main assertion in the ODSF (that PtDAs address decisional needs and improve decision quality).