The effect of cognitive retraining after stroke on everyday living: A systematic review and meta-analysis

Abstract

Objective

To determine if the addition of cognitive retraining to rehabilitation following stroke results in better everyday living outcomes.

Data sources

Electronic databases MEDLINE, EMBASE, PsycINFO, CINAHL, OT Seeker and Cochrane Library were searched until January 2025.

Review methods

Randomised controlled trials were included if they measured change in function and investigated a cognitive retraining intervention aimed at restoration of impaired cognition in one or more specific cognitive domains in the adult stroke population. Papers were excluded if they exclusively provided interventions that were not restorative, such as compensatory approaches or direct task retraining. Two independent reviewers extracted data and assessed study quality.

Results

Twenty-one studies involving 1476 participants were included. There was very low-quality evidence that basic activity of daily living (ADL) was not improved by the addition of cognitive retraining (standardised mean difference (SMD) 0.48, 95% confidence interval (CI) −0.04 to 1.01). There was moderate quality evidence that cognitive retraining had no effect on Instrumental ADL (IADL) (SMD −0.19, 95% CI −0.65 to 0.27) or other measures of functional performance (SMD −0.03, 95% CI −0.31 to 0.24).

Conclusions

Cognitive retraining focusing on restoration of one or more cognitive domains after stroke did not show an impact in basic ADL performance, IADL performance, or other measures of functional performance. Results were complicated by low-quality evidence and methodological factors including variations in study populations, interventions provided and outcome measures. Further research that includes suitable measures of everyday living is needed to provide more robust evidence and guide clinical practice.

Keywords

Activities of daily living cognitive impairment stroke rehabilitation interventions extended activities of daily living (EADL)

Introduction

Cognitive impairment resulting from stroke is a significant issue, affecting approximately 30–70% of survivors of stroke.¹ The impact of cognitive impairment can be profound, including poor functional outcomes,^2,3 reduced independence,⁴ higher risk of depression,⁵ lower quality of life (QoL)^6,7 and diminished recovery in other areas due to poor participation in rehabilitation.^8,9

Cognitive rehabilitation is a broad therapeutic approach commonly used to address cognitive impairment after stroke and encompasses three main approaches: restorative, compensatory and knowledge acquisition.^10–13 Compensatory techniques aim to work around cognitive deficits and rely on intact cognitive skills, strategies and supports to improve daily functioning, rather than trying to recover impaired cognitive abilities.¹³ Knowledge acquisition involves teaching specific information relevant to daily life using strategies such as vanishing cues and errorless learning, without expecting an overall improvement in general cognition.¹³ In contrast, a restorative approach focuses on directly improving cognitive function, aiming to reverse, minimise, or prevent deficits in specific cognitive domains, such as attention, memory, problem solving, or executive functioning.^11,13 Cognitive retraining, a key component of the restorative approach, typically involves a programme of structured and repetitive cognitive tasks designed to strengthen or remediate impaired functions.¹⁴

The capacity of cognitive retraining to improve cognition in specific domains has been reported in several systematic reviews.^15–20 Improvements at the impairment level are suggested to generalise to everyday living skills, however, evidence for this in the stroke population has not been firmly established. Functional outcomes have been included in reviews focusing on cognitive rehabilitation as a whole,¹⁶ on specific interventions such as computerised retraining,^18,21 and on specific cognitive domains such as attention,²² memory,²³ working memory,²⁴ and executive function.^10,25 Nevertheless, these reviews do not comprehensively evaluate everyday living outcomes in the stroke population as functional performance was not the primary focus, or they included mixed acquired brain injury (ABI) populations. Contemporary stroke guidelines advocate that rehabilitation should focus on increasing participation in meaningful activities or reintegration into everyday life, rather than specific impairments.^26,27 Therefore, a synthesis of evidence to inform clinical practice is needed. A systematic review by Hoffman et al.²⁸ in 2010 explored the effect of cognitive rehabilitation interventions on function in individuals following stroke. Four studies were identified at that time, of which only two involved cognitive retraining interventions, and no definitive recommendations could be made. In recent years, interest in cognitive retraining has increased, particularly with the introduction of more computerised retraining programmes, warranting an update of the literature. Thus, the aim of this systematic review was to determine whether the addition of cognitive retraining focusing on restoration of cognitive function to rehabilitation programmes results in better everyday living in adults after stroke.

Methods

The review was completed in accordance with Preferred Reporting Items of Systematic Review and Meta-Analyses (PRISMA) guidelines^29,30 and registered with the International Prospective Register of Systematic Reviews (PROSPERO, https://www.crd.york.ac.uk – reference CRD42016047087).

A systematic search was performed of Medline Ovid, PsycINFO Ovid, OT Seeker, CINAHL, EMBASE and Cochrane databases from the earliest records to January 2025. Key concepts of ‘stroke’, ‘cognition’ and ‘rehabilitation’ were used. Key words and their synonyms within these concepts and MeSH terms were combined with the OR operator and then combined using the AND operator (see Supplemental Appendix 1 for the full search strategy).

To be eligible for the review, studies had to be randomised controlled trials and meet the following criteria: (a) participants aged 18 years old or older; (b) at least 50% of participants had a clinical diagnosis of stroke; (c) participants had impaired cognitive function at baseline, demonstrated by objective assessment or self-report; (d) intervention group received a cognitive retraining programme aimed at restoring function in one or more specific cognitive domains; and (e) a functional outcome measure was used as either a primary or secondary outcome. Studies were excluded if they adopted a compensatory or knowledge acquisition approach rather than restitution of impaired cognitive function. Additionally, studies that exclusively targeted perceptual deficits, such as visual attention or praxis, were excluded, based on the definition of cognitive domains in the Australian Stroke Guidelines.^26,28 Articles not published in English were also excluded. Studies investigating combined interventions, such as cognitive retraining with aerobic exercise,³¹ were also excluded as it was not possible to isolate the effects of the cognitive retraining component. Outcome measures were deemed functional if they: (a) measured performance in activities of daily living (ADLs); (b) measured participation in functional activities; (c) assessed the functional impact of cognition in ADL; or (d) measured attainment of a functional goal. The phase of rehabilitation was determined according to mean time post-stroke reported by the original authors and was categorised as: (a) acute: the first days to several weeks of inpatient treatment; (b) subacute: after acute phase and up to six months; or (c) chronic: longer than six months.³²

Two authors (JW and KJL) independently screened titles and abstracts. Full text copies were obtained for articles that seemed to meet eligibility criteria, or if eligibility was unclear. Consensus was reached on any discrepancies between included and excluded articles through discussion. Where articles could not be accessed, the author was contacted. The same two authors independently determined whether full texts were included with consensus achieved through discussion. Reference lists of included studies were screened for any additional studies not found through the database search, and citation tracking of all included studies was completed using Google Scholar.

Data extraction and quality assessment

From the included studies, the following data were extracted: full reference details; sample characteristics (diagnosis, age, time since injury); intervention and control descriptions (setting, cognitive domain targeted, duration, intensity, total dosage received), and outcomes (results of functional outcome measures). One reviewer performed the data extraction, and a second reviewer checked it for accuracy. Two reviewers (JW and KJL) assessed the scientific quality of included trials using the PEDro Scale, a validated measure of methodological quality in clinical trials.^33,34 Disagreement between the reviewers was resolved through discussion until consensus was reached. Study quality was categorised based on PEDro scores as follows: ‘excellent’ (9–10 points), ‘good’ (6–8 points), ‘fair’ (4–5 points) and ‘poor’ (≤3 points).³⁵ The Template for Intervention Description and Replication (TIDieR) checklist was employed to evaluate the quality of intervention descriptions.³⁶ Two reviewers applied the checklist independently, resolving any disagreements through discussion. Results were reported as percentage of items achieved.

Data synthesis and analysis

A narrative synthesis of results was completed, and studies were grouped according to the domain of everyday living they measured. Meta-analysis was completed using Review Manager Version 5.3 software when studies used sufficiently homogenous outcome measures. Data from pre-intervention and immediately post-intervention was used for meta-analysis. Studies were combined using the inverse variance method and a random effects model. A standardised mean difference (SMD) was calculated for each continuous outcome; A SMD of 0.2 indicated a small effect, 0.5 a moderate effect and 0.8 a large effect.³⁷ Where standard deviations were not reported, they were calculated using alternative methods.³⁸ Heterogeneity was assessed using visual inspection and the I² statistic was used to estimate the percentage of total variation across studies due to heterogeneity rather than chance, with values exceeding 50% indicative of considerable heterogeneity.³⁹ Where high levels of statistical heterogeneity were evident (I²> 25%) sensitivity analyses were completed to assess the impact of time since stroke and intervention type. The Grades of Research, Assessment, Development and Evaluation (GRADE) approach was applied to each meta-analysis performed to determine the quality of the evidence.^37,40 This involved grading the evidence as ‘high’, ‘moderate’, ‘low’ and ‘very low’ based on criteria for: (a) inconsistency of results (downgrade if I² > 50%, indicating high heterogeneity, and there was no plausible explanation to explain the inconsistency of results); (b) indirectness of results; (c) imprecision of results (downgrade applied if large confidence interval (CI), defined as a total interval > 25% representing a quartile); and (d) risk of bias across studies (downgrade if mean PEDro score average < 6).

Results

After removing duplicates, 2682 references were identified through the electronic database search. Seven additional articles were found through citation tracking and reference checking. After applying eligibility criteria (Table 1) to the titles and abstracts, 93 full text articles were identified for assessment of eligibility and produced a yield of 21 articles in the final review (Figure 1).

Table 1.

Inclusion criteria.

Inclusion criteria
Population	Adults 50% participants have clinical diagnosis of stroke Identified cognitive impairment
Intervention	Cognitive retraining programme Must aim to restore cognitive function at the impairment level, in one or more specific cognitive domains
Comparison	Group that does not receive cognitive retraining intervention May include waitlist control, usual care, or alternative intervention
Outcomes	Measures performance in activities of daily living (ADL), or Measures participation in functional activities, or Measures functional impact of cognition in ADL, or Measures attainment of a functional goal
Study design	Randomised trials
Sources	Peer-reviewed journal articles
Languages	Papers published in English

Description of included studies

Quality assessment

Due to difficulty blinding therapists to cognitive retraining interventions, the maximum possible total PEDro score was 9 out of 10 points. The mean score was six (SD 1.4) (Supplemental Appendix 2), and 14 studies (66.7%) had a score of six or higher, reflecting high methodological quality generally (Table 2).

Table 2.

Included studies.

Paper	Number of participants (n)% participants with strokeMean ageMean time since injurySetting (inpatient/outpatient, country)	Quality of study (PEDro score)	Cognitive domain targeted	Intervention therapy:n participantsIntervention descriptionIntensityTotal therapy provided	Control or comparator therapy:n participantsDescription	Outcome measures used: domain of Everyday LivingTime points
Akerlund et al. (2013)⁴⁴	n = 47 71% stroke 47.7 years old 32 weeks post-injury Outpatient setting in Sweden	6	Working memory	n = 25 Cogmed QM program 30–45 minutes, 5 days per week for 5 weeks Total therapy: 12.5 hours	n = 20 Usual care	DEX: other Baseline Post-intervention 18-week follow-up
Barker Collo et al. (2009)⁶⁰	n = 78 100% stroke 69 years old 18.5 days post-injury Combination of inpatient and outpatient setting in New Zealand	8	Attention	n = 38 Attention process training 60 minutes, 5 days per week for 4 weeks Total therapy: 20 hours	n = 40 Usual care	CFQ: other SF-36: QoL 6-month follow-up
Bjorkdahl et al. (2013)⁴⁵	n = 38 74% stroke 51 years old 27 weeks post-injury Outpatient setting in Sweden	4	Working memory	n = 20 Cogmed QM program 30–45 minutes, 5 days per week for 5 weeks Total therapy: 12.5–18.8 hours	n = 18 Usual care	WMQ: other AMPS: other Baseline Post-intervention 3-month follow-up
Carter et al. (1988)⁵⁴	n = 33 100% stroke 70.5:73.4 years old 4.81:4.6 days post-injury Inpatient rehabilitation setting in United States of America.	5	Visual scanning, visual spatial perception, judgement skills	n = 16 Cognitive skills retraining from thinking skills workbook 30–40 minutes, 3 times per week, average of 3–4 weeks Total therapy: 4.5–8 hours	n = 17 Usual care	Barthel: basic ADL Baseline Post-intervention
Cho, Kim & Jung (2016)⁴⁸	n = 44 100% stroke 63 years old 5.1:6.5 months post-injury Inpatient setting in Korea	5	Attention, concentration, memory	n = 14 RehaCom computer program 30 minutes, 5 times per week, for 6 weeks Total therapy: 15 hours	n = 16 Standard care	FIM: basic ADL Baseline Post-intervention
De Luca et al. (2014)⁵⁵	n = 35 51.43% stroke 35.97 years old 3–6 months post-injury Outpatient setting in Italy	4	Memory, executive functions, and abilities of thinking	n = 15 PC training – combination of software and free web based graded resources 3 times per week for 8 weeks (duration of each session not stated) Total therapy: unclear	n = 20 Usual care	Barthel: basic ADL ADL scale: basic ADL IADL: IADL Baseline Post-intervention
Han (2024)⁵⁷	n = 452 100% stroke 68.1 years old ≥1-month post-injury Hospital, nursing home, community, home settings in China	8	Memory, attention, execution, calculation, thinking, and perception	n = 57 Mobile intelligent cognitive training application 30 minutes, 5 times per week for 12 weeks Total therapy: 30 hours	n = 55 Comprehensive management of post-stroke cognitive impairment	MBI: basic ADL FAQ: other QLI: QoL Baseline 6 weeks Post-intervention 16-week follow-up
Ho (2022)⁴¹	n = 39 100% stroke 64.55 years old 29.97 months post-injury Outpatient setting in Taiwan	5	Information processing speed, attention, memory	n = 19 Computerised cognitive training with Lumosity program 20 minutes, 2 times per week for 12 weeks Total therapy: 8 hours	n = 20 Therapist-led conventional cognitive training	SIS: other Baseline Post-intervention 4-week follow-up
Kim (2021)⁴⁹	n = 32 90.6% stroke 64.7 years old 25.1 days post-injury Inpatient setting in Korea	7	Complex attention and executive functioning: divided attention, working memory, calculation, and planning	n = 18 RehaCom computer program 30 minutes, 5 times per week, for 2 weeks Total therapy: 5 hours	n = 14 Therapist-driven cognitive rehabilitations 30 minutes, 5 times per week for 2 weeks Total therapy: 5 hours	MBI: basic ADL Baseline Post-intervention
Lundqvist et al. (2010)⁶¹	n = 21 52% stroke 43.2 years old 37 months post-injury Outpatient setting in Sweden	5	Working memory	n = 10 QM computer WM program 45–60 minutes, 5 days per week, for 5 weeks Total therapy: 18.75–25 hours	n = 11 No treatment	COPM: other EQ-5D: QoL Baseline 20-week follow-up
Man et al. (2006)⁵²	n = 103 54% stroke 42.68: 48.55 years old 3.46:4.13 years post-injury Outpatient setting in Hong Kong	8	Problem solving	n = 25 Tele-analogy online problem-solving training 20 × 45-minute sessions Total therapy: 15 hours	n = 20 No treatment (waitlisted) n = 28 Computer-assisted training N = 30 Therapist administered training	Lawton IADL scale: IADL Baseline Post-intervention
Poulin et al. (2017)⁵⁰	n = 9 100% stroke 49.25 ± 11.35 years old 6.2 months Outpatient setting (home based) in Canada	6	Executive function	n = 4 Computerized EF training 16 sessions (mean 59.2 ± 5.3 minutes) – twice weekly for eight weeks Total therapy: 15.7 hours	n = 5 CO-OP strategy training 16 sessions (mean 57.5 ± 11.3 minutes) – twice weekly for eight weeks	COPM: other DEX: other Baseline Post-intervention One month follow-up
Prokopenko et al. (2013)⁵⁸	n = 43 100% stroke 61:66 years old Within 2 weeks post-injury Inpatient in Russia	6	Attention, visual and spatial gnosis	n = 24 Computerized Shulte's tables, figure background 25–35 minutes every day for 2 weeks Total therapy: 5.8–8.2 hours	n = 19 Standard treatment	DEX: other IADL: IADL SSQL: QoL Baseline Post-intervention 18-week follow-up
Richter et al. (2015)⁴⁶	n = 44 69% stroke 65.4:56.6 years old 60 days post-injury Inpatient in Germany	6	Working memory	n = 18 WOME software package 9 × 30-minute sessions Total therapy: 4.5 hours	n = 18 Standard memory treatment 3 × 1 hour group therapy sessions per week	CFQ: other Baseline Post-intervention
Soderback (1988)⁵³	n = 67 52% stroke 49.7:46.8 years old Acute (exact time since stroke not specified Inpatient setting in Sweden	3	Attention, spatial, verbal, numerical, praxis, memory, and logical functions	n = 15 Intellectual function training + rehabilitation (IFT + R) Total therapy: 37 hours	n = 18 Rehabilitation Only (R) n = 19 Intellectual housework + rehabilitation (IH + R) n = 15 Intellectual function training + intellectual housework + rehabilitation (IFT + IH + R)	IHA: other Baseline Post-intervention 168 day follow-up
Van de ven et al. (2017)⁵¹	n = 97 100% stroke 60 years old 3 months–5 years post-injury Outpatient setting in The Netherlands	7	Attention, memory, and reasoning.	n = 38 Braingymmer 58 × 30-minute sessions, 5 sessions per week Total therapy: 29 hours	n = 24 Waitlist control n = 35 Mock training	CFQ: other DEX: other Lawton IADL: IADL SF-36: QoL Baseline 6 weeks Post-intervention 4-week follow-up
Weiker et al. (2020)⁴⁷	n = 20 55% stroke 48.5 years old 16 months post-injury Outpatient clinic in Germany	8	Working memory	n = 11 Standard compensatory therapy + WOME (WOrking MEmory; RehaCom^®, Hasomed GmbH) Daily on weekdays for four weeks, 30 minutes each Total therapy: 10 hours	n = 9 Standard compensatory therapy + attention control non-specific cognitive training	Everyday life performance: other Baseline Halfway (2 weeks) Post-intervention
Wentink et al. (2016)⁴²	n = 110 100% stroke 59 years old 26 months: 25 months post-injury Outpatient setting in The Netherlands	8	Attention, speed, memory, flexibility, problem solving	n = 53 Lumosity program 15–20 minutes, ≥5 days per week for 8 weeks Total therapy: 10–13.3 hours	n = 57 Brain education	CFQ: other SS-QoL-12: QoL Baseline Post-intervention 16-week follow-up
Westerberg et al. (2007)⁵⁹	n = 18 100% stroke 54 years old 12–36 months post-injury Outpatient setting (home based) in Sweden	6	Working memory	n = 9 Software product – RoboMemo 40 minutes, 5 times per week, for 5 weeks Total therapy: 18.75 hours	n = 9 No treatment	CFQ: other Baseline Post-intervention
Withiel et al. (2019)⁴³	n = 65 100% stroke 60.9 (12.8) years old 41.7 (44.8) months post-injury Community dwelling in Australia	7	Memory	n = 22 Lumosity program 30 minutes a day, 5 days a week for 6 weeks Total therapy: 15 hours	n = 19 Waitlist control n = 24 Memory skills group	GAS: other EMQ: other Baseline Post-intervention 6-week follow-up
Zucchella et al. (2014)⁵⁶	n = 92 100% stroke 65:70 years old Within 4 weeks post-injury Inpatient setting in Italy	6	Time and spatial orientation, visual attention, logical reasoning, executive functioning	n = 42 Una palestra per la menta, training di rihabilititazone cognitiva – computer programs 45-minute sessions, 4 times per week, for 4 weeks Total therapy: 12 hours	n = 45 Usual care	FIM: basic ADL Baseline Post-intervention

ADL: activity of daily living; AMPS: assessment of motor and process skills; CFQ: Cognitive Failures Questionnaire; COPM: Canadian Occupational Performance Measure; DEX: Dysexecutive Questionnaire; EMQ: Everyday Memory Questionnaire; EQ-5D: EuroQol-5 Dimension; FAQ: Functional Activities Questionnaire; FIM: Functional Independence Measure; GAS: Goal Attainment Scale; IADL: Instrumental ADL; IHA: Intellectual Housework Assessment; MBI: Modified Barthel Index; PEDro: Physiotherapy Evidence Database; SF-36: 36-Item Short Form Health Survey; SIS: Stroke Impact Scale; SS-QoL-12: Stroke Specific Quality of Life Scale; QLI: quality of life index; QoL: quality of life; WMQ: Working Memory Questionnaire.

Participant characteristics

In total, 1476 participants were included across 21 studies, with 717 receiving cognitive retraining interventions (Table 2). Median study sample size was 43 participants (range 11–452). Males constituted 59% of the participants, and average age was 56.7 years. Twelve papers (57%) exclusively investigated post-stroke populations, while the remaining studies included participants with mixed ABI aetiologies, such as traumatic brain injury, tumours and infection. Details of the specific location and type of infarct were provided in four studies, with two of these also detailing stroke severity. Nine studies specified the type of stroke and the affected cerebral hemisphere. However, the remaining studies offered little or no detail on stroke characteristics. Time post-stroke varied considerably (range: less than two weeks to 46 months), with chronic phase survivors of stroke being most represented (n = 12/21, 57%), followed by acute and subacute phases (four studies each, 19%). One study did not specify the time post-stroke. Seven studies were conducted in inpatient settings and 12 were conducted in outpatient settings, with four of these involving therapies in participants’ homes.

Interventions

Computer-based programs constituted most of the interventions (n = 18/21, 85.7%), followed by pen and paper methods (n = 2/21, 9.5%), and therapist-led training programmes (n = 1/21, 4.8%). Eleven different computer programs were used throughout the studies. The most common programs were Lumosity (n = 3/10, 14%),^41–43 Cogmed QM (n = 2/21, 9.5%),^44,45 WOME (WOrking MEmory; RehaCom^®, Hasomed GmbH) (n = 2/21, 9.5%),^46,47 and RehaCom (n = 2/21, 9.5%).^48,49 Occupational therapists delivered interventions in two studies (9.5%), neuropsychologists in two studies (9.5%), and research assistants (discipline not specified) in three studies (14%). In the remaining 14 studies (66.7%), participants received supervision or regular contact from researchers, but interventions were self-directed.

Control conditions varied with no treatment in two studies (9.5%), standard care only in 10 studies (47.6%) and standard care plus an active control in two studies (9.5%).^42,47 One study compared cognitive retraining with an alternative therapy; a problem-solving strategy training programme named Cognitive Orientation to Daily Occupational Performance (CO-OP).⁵⁰ Two studies compared computerised cognitive training with therapist-led, conventional cognitive training.^41,49 Two studies included a waitlist control plus a second control group; one was an alternative therapy (memory group),⁴³ and the other was mock training.⁵¹ The remaining two studies included multiple control groups, including no treatment and alternative therapies.^52,53

On average, cognitive retraining was delivered over 6.3 weeks (range 2–12 weeks), with a mean total duration of 15.5 ± 8.7 hours. Interventions targeted multiple cognitive domains or general cognitive function in 11 studies (52.4%), working memory in six studies (28.6%), attention in one study (4.8%), and memory, problem solving, and executive functioning in one study each (4.8% each).

Papers achieved an average of 72% of TIDieR items, indicating incomplete reporting of interventions. The most underreported aspects were modification of interventions throughout the study (item 10, 10%), planned assessment of fidelity (item 11, 33%), actual intervention adherence (item 12, 52%), and details of intervention provider (item 5, 52%). See Supplemental Appendix 3 for full details of TIDieR scores.

Outcome/synthesis of results

Outcome measures varied considerably, with 16 different tools utilised across the studies. All studies used standardised outcome tools. The most commonly used tools were the Cognitive Failures Questionnaire (five studies), and the Modified/Barthel Index and Dysexecutive Questionnaire (DEX) (four studies each), followed by the Functional Independence Measure (FIM), Instrumental ADL (IADL) scale, Lawton IADL scale and Canadian Occupational Performance Measure (COPM) (two studies each). All outcomes are listed in Table 2. A functional measure was the primary outcome in 7 studies (33.3%) and 12 studies (57%) performed a follow-up measurement beyond the immediate post-intervention period. Method of outcome collection was self-report via questionnaires (n = 12/21, 57%); observer ratings (n = 6/21, 28.6%), and semi-structured interviews n = 3/21, 14%). Participants were assisted in completing self-rated questionnaires by carers or therapists in two studies, and in two additional studies, ratings were completed by a proxy alongside the participant.

Outcomes were grouped into the following domains: basic ADL (six studies), instrumental ADL (four studies), and other measures of functional performance (15 studies). QoL was measured in six studies.

Effects of intervention on everyday living

Meta-analysis was possible for three domains of everyday living (Table 3).

Table 3.

Summary of meta-analysis and GRADE results.

Outcome	Number of trials	Number of participants	Intervention	Control	SMD (95% CI), I²	Quality of evidence (GRADE)
Basic ADL	6	334	Thinking skills workbook targeting multiple cognitive domains (1 study) Computerised retraining targeting multiple cognitive domains (5 studies)	Usual care (5 studies) Cognitive retraining therapist led/usual care	0.48 (−0.04 to 1.01), 80%	Very low^a,b,c
IADL	4	199	Tele-analogy based problem solving programme (1 study) Computerised (3 studies)	Usual care (2 studies) Waitlist control (2 studies)	−0.19 (−0.65 to 0.27), 61%	Moderate^a
Other functional performance	3	201	Computerised (3 studies)	Usual care (1 study) Brain training (1 study) No therapy (1 study)	−0.03 (−0.31 to 0.24), 54%	Moderate^a

SMD: standardised mean difference; CI: confidence interval; ADL: activities of daily living; IADL: Instrumental Activities of Daily Living.

Reason for downgrade: inconsistency (I² > 50 and no plausible explanation to explain inconsistency of results).

Reason for downgrade: high risk of bias (mean PEDro score < 6, not explained by any weighted studies).

Reason for downgrade: imprecision of results (large confidence interval).

Basic ADL

Meta-analysis of six studies,^{48,49,54–57} comprising 334 participants, provided very low-quality evidence with moderate effect size that there was no benefit of cognitive retraining over usual care on basic ADL at the completion of intervention (SMD 0.48, 95% CI −0.04 to 1.01) (Figure 2). Only one study completed follow-up measures of basic ADL beyond the intervention period.

Instrumental ADL

Meta-analysis of four studies,^51,52,55,58 comprising 199 participants, provided moderate quality evidence with small effect size that cognitive retraining had no effect on IADL performance upon completion of intervention (SMD −0.19, 95% CI −0.65 to 0.27) (Figure 3).

Other measures of functional performance

Meta-analysis of three studies,^42,51,59 comprising 201 participants, provided moderate quality evidence with small effect size that there was no difference in functional performance, based on self-report of cognitive failures, in everyday life (SMD −0.03, 95% CI −0.31 to 0.24) (Figure 4). Two additional studies used the same outcome measure but provided insufficient point data to be included in meta-analysis. Both papers reported no significant impact of treatment.^46,60

Of the remaining 10 studies not included in meta-analysis, four investigated working memory retraining programmes and found no significant benefit over control groups.^44–46,61 One found memory retraining was effective at completion of intervention, but not at follow-up, and was inferior to a memory group intervention.⁴³ Other papers reported no benefit of computerised training,⁴¹ executive functioning training⁵⁰ or attention process training.⁶⁰ One paper did find the intervention group self-reported better improvements in daily routines, but this was not statistically analysed.⁴⁷ The remaining study reported improved performance on an intellectual housework assessment following cognitive retraining.⁵³

Quality of life

Six studies^{42,51,58,60–62} used five different measures of QoL. One study reported improved QoL post-intervention and at 16 weeks follow-up,⁶² while all other studies reported no significant difference in QoL between groups. Meta-analysis was not possible due to heterogeneity of outcome measures.

Discussion

This systematic review of 21 randomised controlled trials suggests that cognitive retraining focusing on restoring impaired cognitive function does not impact basic ADL in post-stroke rehabilitation, based on very low-quality evidence. There is moderate evidence that IADL performance and subjective cognitive function are not impacted. Narrative synthesis indicates that other measures of functional performance and health-related QoL are also unaffected by cognitive retraining. Previous reviews have not provided clear recommendations for or against cognitive retraining in stroke rehabilitation due to a lack of large, high-quality trials and uniform outcome measures.^17,28 Rather than evidence against a restorative approach, limited data from existing papers with primary outcomes focusing on cognitive function at the impairment level have guided practice in this area to date.^17,22,63 Our review adds to the literature by focusing specifically on the relationship between cognitive retraining using a restorative approach and everyday living outcomes in survivors of stroke.

Increased interest in cognitive retraining, particularly online ‘brain training’ programmes, is highlighted by the high number of papers in our review compared with the previous review by Hoffman et al.²⁸ Regardless, the impact of cognitive retraining on everyday living remains unclear as functional outcome measures are scarce and often not the primary measure. Even when used, tools like ADL performance scales or subjective cognitive failure assessments often do not reflect meaningful changes in everyday living. For instance, whilst trials in the basic ADL meta-analysis used valid measures for basic ADLs, such as eating, dressing and mobility,^64,65 these aspects represent only a part of everyday living. Many people with cognitive deficits recover in basic ADLs but do not return to work, study, or other more complex activities. Moreover, basic ADL test items may not be sensitive to improvements in higher functions.⁶⁶ Rehabilitation following stroke should focus on the individual's own specific goals, and aim to improve participation in life situations and activities, rather than solely addressing impairments.^26,27,67 Only two studies measured participants’ own functional goals, and there was a lack of tools measuring broader participation such as employment, community integration, education or leisure activities. The heterogeneity of outcome measures also precluded half of the included papers from meta-analysis. To improve participation in everyday activities, future studies need to consistently use appropriate and standardised measures to gain insight into how these therapies influence meaningful change for survivors of stroke.

Given the low quality of evidence, this review suggests that other approaches with a stronger evidence base may show greater promise for improving everyday living outcomes. Contemporary reviews within the ABI field recommend addressing cognitive concerns with meta-cognitive strategy training,^67,68 global cognitive strategy training,⁶⁹ and comprehensive, holistic, compensatory approaches, to improve performance and participation in daily activities.^12,13,67 Although evidence for these approaches with survivors of stroke specifically has not been comprehensively demonstrated in the literature, they may be more favourable over cognitive retraining programmes given their support in the wider ABI population.

While this review contributes information regarding whether particular programmes support survivors of stroke to return to everyday living, further clarity is needed on how and when to provide therapies for the greatest meaningful improvement.⁷⁰ Factors such as cognitive domain targeted, delivery method, dosage and intensity likely impact cognitive retraining effectiveness. Subgroup analysis of these factors was not possible due to heterogeneity of retraining programmes and outcome measures throughout the studies in this review and further research is needed to determine their impact. In light of recent evidence that suggests the largest improvements in cognition occur during acute and subacute phases post-stroke,^17,71 further exploration of whether this extends to everyday living would be beneficial. The majority of studies in our review involved self-directed computer-based interventions, shown to improve objective cognitive functions in stroke populations,^18,72 and suggested to improve ADL in one review.⁷² However, our subgroup analysis found no significant impact on basic ADL and IADL outcomes. Furthermore, a recent review suggests a dose-response and diminishing returns relationship exists, with effects plateauing around 20 hours of treatment.¹⁷ Most studies did not meet this threshold, suggesting the amount provided may have been inadequate to elicit functional change.

Understanding how cognitive retraining interventions impact cognition at the cortical level and translate to functional performance would also enable more strategic application of therapy to optimise outcomes for survivors of stroke. Knowledge of how patient factors such as stroke characteristics,⁷³ phase of rehabilitation and level of cognitive impairment are relevant in predicting potential for recovery⁷⁴ and efficacy of specific interventions,⁷⁵ is evolving. Studies contained limited details of participants’ stroke characteristics, and none explored correlations between stroke characteristics and functional outcomes, highlighting an important field for future research.

Several limitations are noted in this review. The heterogeneity of outcome measures precluded many studies from meta-analysis. Application to clinical practice and any specific individual is limited due to variation in participant characteristics, and a lack of clarity around the relationship between statistically significant change scores in functional outcomes and clinically relevant changes for survivors of stroke. More complete reporting of methodology and description of interventions would allow replication for research or clinical settings. Evaluation of the longitudinal impact of cognitive retraining was limited, as no studies used sufficiently homogenous outcome measures beyond the intervention period. Nonetheless, this review included a relatively high number of studies, with only randomised controlled trials, and meta-analysis was possible for some domains of everyday living. The clinical population consisted of majority or exclusively survivors of stroke, making it appropriate to apply results to the general stroke population. PRISMA guidelines were followed, and the TIDieR checklist was used, resulting in a comprehensive and transparent systematic review.

Cognitive retraining programmes focusing on restoration are more available than ever before, making it important to determine their value for survivors of stroke. This systematic review suggests that cognitive retraining after stroke may not improve performance in basic or instrumental activities of daily living. Given the current evidence, focusing on other approaches to cognitive rehabilitation may be more beneficial than interventions aiming to restore cognitive deficits at the impairment level. Larger scale studies with standardised use of appropriate outcome measures are vital to provide more compelling evidence regarding the impact of cognitive retraining on everyday living.

Clinical messages

Cognitive retraining aimed at restoration has not shown significant improvements in functional outcomes related to everyday living.

Based on current evidence, alternative approaches to cognitive rehabilitation may be more effective in supporting return to everyday activities after stroke.

Future studies should include measurement of individuals’ own specific rehabilitation goals and participation in life situations.

Supplemental Material

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Supplemental material, sj-docx-3-cre-10.1177_02692155251336981 for The effect of cognitive retraining after stroke on everyday living: A systematic review and meta-analysis by Jennifer White and Kylee J Lockwood in Clinical Rehabilitation

Footnotes

Declaration of conflicting interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The authors received no financial support for the research, authorship, and/or publication of this article.

ORCID iDs

Jennifer White

Kylee J Lockwood

Supplemental material

Supplemental material for this article is available online.

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