Active control-group designs in cognitive rehabilitation trials: a qualitative review of computer-based rehabilitation in patients with acquired brain injury

Background and Objectives: To outline experimental variables of relevance to clinical trials employing active control condition (ACC) designs within cognitive rehabilitation after Acquired Brain Injury (ABI), and to qualitatively review the current methodology of trials within this field. Method: Firstly, experimental variables which evidently impact rehabilitation outcome were outlined, based on the authors’ joint knowledge of the research field. Secondly, clinical trials within cognitive rehabilitation after ABI that employed ACC designs were identified and qualitatively evaluated based on the outlined variables. Due to the breadth of this research field, a focus on computer-based cognitive rehabilitation (CBCR) was chosen. Trials were identified through a systematic search in prespecified scientific databases using prespecified inclusion criteria. Results: 10 experimental variables were identified. Nine trials were included in this review. None of the included trials accounted for all experimental variables in their study design. Conclusion: There are methodological shortcomings in the design of trials using ACC’s within the field of CBCR after ABI. Although this methodological review is limited to a subfield within cognitive rehabilitation research, the conclusions drawn here are believed to generalize to the overall field. The experimental variables outlined here may aid researchers in the design phase of future trials using ACC’s.