Desjardins‐Crépeau 2016.

Methods	Design: 2 × 2 factorial RCT design Recruitment period: not reported No. of centres involved: not reported Unit of randomisation: individuals No. randomised: 136 participants Number of arms considered in this review: 4 Maximum trial duration: 12 weeks. Funding by non‐profit organisation: this study was supported by a Canadian Institutes of Health Research (CIHR) grant (#187596). One study author was supported by a doctoral fellowship from the CIHR, and the other study author was supported by the Canada Research Chair Programme Funding by commercial organisation: none reported Publication status: full‐text report
Participants	Patient flow: 136 participants were randomised, 91 completed the programme, and 76 were considered in the report. Each of 38 participants had aerobic and resistance (AR) and stretching and toning (ST) exercises. Of these, 22 in AR and 20 in ST received the computerised stimulation (experimental group), and 16 in AR and 18 in ST received computer lessons (control group), respectively Number of females: arm with AR: 13 of 22 (59%) in experimental group, 8 of 16 (50%) in control group; arm with ST: 17 of 20 (85%) in experimental group, 15 of 18 (83%) in control group Average age (SD): arm with AR: 72.7 (7.4) years in experimental group, 70.9 (7.4) years in control group; arm with ST: 73.2 (6.3) years in experimental group, 72.5 (7.0) years in control group Average (SD) education: arm with AR: 14.4 (2.8) years in experimental group, 15.9 (2.1) years in control group; arm with ST: 14.1 (4.3) years in experimental group, 14.1 (3.8) years in control group Baseline cognitive function: MMSE in arm with AR: 28.8 (1.3) in experimental group, 28.8 (1.0) in control group; MMSE in arm with ST: 29.4 (0.7) in experimental group, 28.5 (1.4) in control group Selection criteria on cognition: community‐dwelling participants were recruited from the research centre's participant pool. A telephone‐based screening interview was used to assess the eligibility of each candidate. Exclusion criteria were as follows: history of neurological disease or major surgery in the year preceding the study, auditory or visual impairments that were not corrected, smoking, severe mobility limitations, any other contraindication to perform physical activity, currently engaged in any type of structured physical activity, high score on geriatric depression scale, < 60 years old Ethnicity: not reported APOE: number of participants positive for APOE not reported
Interventions	Type of experimental intervention: computerised cognitive training group; treatment duration 12 weeks; intervention provided in small group format under supervision of a neuropsychologist student Details of experimental intervention: each weekly session of dual task (DT) training took place in a room with 10 computer stations and was supervised by a student in neuropsychology. Participants were trained on a computerised visual DT analog. The task consisted of 2 visual discrimination tasks performed separately and concurrently. The first task was a number discrimination task (3, 5, and 8), and the second was a shape discrimination task (circle, square, and diamond). Participants had to respond to the number or shape presented on the screen with a key press on the appropriate button identified on the keyboard. The DT consisted of 4 different blocks, each containing different types of trials Type of concomitant treatment provided: arm with AR: included two 60‐minute sessions/week for 12 weeks of physical exercise of cardiorespiratory fitness and lower body muscle strength; arm with ST included two 60‐minute sessions/week for 12 weeks of series of exercises aimed at improving flexibility and general motor skills without a specific focus on increasing cardiorespiratory capacity or strength Session duration: 60 minutes in the experimental group Number of treatment sessions: 12 in the experimental group Treatment frequency: 1 session per week Maximum treatment duration in weeks: 12 in the experimental group Type of control intervention: inactive; treatment duration of 12 weeks; intervention provided in group format, under supervision Details of control intervention: computer lessons (control) condition consisted of introductory exercises to computers and diverse software (e.g. Word, Excel), as well as an introduction to the Internet (search engines, websites, online games, etc.). These sessions took place in the same computer room as the DT training programme and were taught by a student in neuropsychology Type of concomitant treatment provided: arm with AR: included two 60‐minute sessions/week for 12 weeks of physical exercise of cardiorespiratory fitness and lower body muscle strength; arm with ST included two 60‐minute sessions/week for 12 weeks of series of exercises aimed at improving flexibility and general motor skills without a specific focus on increasing cardiorespiratory capacity or strength Session duration: 60 minutes in the control group Number of treatment sessions: 12 in the control group Treatment frequency: 1 session per week Maximum treatment duration in weeks: 12 in the control group
Outcomes	Cognitive functioning outcomes considered Episodic memory measured with Rey Auditory Verbal Learning Test, delayed at 12 weeks, on a scale from 0 to 15, with higher values indicating benefit Executive function measured in seconds with the Color‐Word Interference Test (CWIT‐switching) of the Delis–Kaplan Executive Functions System is based on the Stroop procedure at 12 weeks on a scale from not reported to not reported with lower values indicating benefit Speed of processing measured with TMT‐A at 12 weeks on a scale from not reported to not reported with lower values indicating benefit Physical functioning outcome considered: none reported Quality of life outcome considered: none reported Safety outcome considered: none reported Depression outcome considered: none reported Other outcome data on cognitive functioning, not considered in our meta‐analyses Episodic memory measured with Rey Auditory Verbal Learning Test, total 5 trials and immediate recall at 12 weeks, on a scale from not reported to not reported with higher values indicating benefit Executive function measured in seconds with the Color‐Word Interference Test (CWIT‐inhibition) of the Delis–Kaplan Executive Functions System is based on the Stroop procedure, TMT part B at 12 weeks on a scale from not reported to not reported with lower values indicating benefit Executive function measured in seconds with BDT‐DT index at 12 weeks on a scale from not reported to not reported with higher values indicating benefit Speed of processing as measured in seconds with the Color‐Word Interference Test (CWIT‐color naming and seconds) of the Delis–Kaplan Executive Functions System is based on the Stroop procedure and BDT‐simple tasks at 12 weeks in seconds, with lower values indicating benefit
Notes	This study was supported by a Canadian Institutes of Health Research (CIHR) grant (#187596). One study author was supported by a doctoral fellowship from the CIHR, and another study author was supported by the Canada Research Chair Program. Study authors report no conflict of interest in the study We combined data from ST and AR arms
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Judgement: adequate random sequence generation Quote(s): "the study was carried on in waves of 16–32 participants randomly assigned to one of the four training combinations using the website randomization.com"
Allocation concealment (selection bias)	Unclear risk	Judgement: method of allocation concealment not reported Quote(s): "the study was carried on in waves of 16–32 participants randomly assigned to one of the four training combinations using the website randomization.com"
Blinding of participants (performance bias)	High risk	Judgement: blinding not feasible
Blinding of personnel (performance bias)	High risk	Judgement: blinding not feasible
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Judgement: explicit reporting of blinded outcome assessment Quote(s): "the evaluators at both pretest and posttest were blind to the group membership of participants"
Incomplete outcome data (attrition bias) All outcomes	High risk	Judgement: we judged high risk of bias, as on average less than 90% of randomised participants were analysed Quote(s): "among the 125 participants who were enrolled in the study, 91 participants completed the program. Among those, three participants failed to participate in the posttest evaluations and two participants had invalid data due to illness at posttest examinations and were thus excluded from analyses"
Selective reporting (reporting bias)	Low risk	Judgement: all outcomes described in the methods section are adequately addressed in the results section
Other bias	Low risk	Judgement: no other sources of bias detected