Study design and randomization
memory complaints
This study was a multicenter, outcome assessor-blinded, 24-week, RCT with a multi-arm parallel design performed in three hospitals and five public health centers across South Korea. The study participants were selected from among older adults who visited outpatient clinics or public health centers for memory complaints. As described in the Introduction, this study was originally designed to examine whether various outcomes were improved in the groups that received the FMI and HMI programs of the SUPERBRAIN compared with the control group. In a 1:1:1 ratio, participants were randomly assigned to the one of three groups: FMI, HMI, and control groups. Randomization was achieved through a permuted block randomization method, and the outcome assessors remained blinded to the assigned groups. Participants were instructed not to discuss their study involvement with the outcome assessor. We previously described the detailed study protocol [The study was performed in accordance with the International Conference on Harmonization Good Clinical Practices Guidelines. Institutional review boards approved the protocol and consent forms at each institution before the study began. Written informed consent was obtained from all potential study participants before their enrollment. This trial was registered with ClinicalTrials.gov (NCT03980392) [