Factors associated with adherence to tablet‐based cognitive training: J‐MINT study

Abstract

INTRODUCTION

Cognitive training is a key component of multidomain interventions to prevent cognitive decline; however, low adherence remains a challenge. In this post hoc analysis of the Japan‐Multimodal Intervention Trial for Prevention of Dementia (J‐MINT), factors associated with cognitive training adherence in older adults with mild cognitive impairment were investigated.

METHODS

J‐MINT was an 18‐month randomized controlled trial. The analyses included 191 participants (intervention group) who completed the trial. Adherence was assessed by calculating the number of days the participants engaged in tablet‐based cognitive training for at least 30 min.

RESULTS

Vision difficulty and a larger friend network were negatively associated with adherence. Female sex, higher cognitive function, and satisfaction with training tasks and implementation goals were positively associated with adherence.

DISCUSSION

The results imply that not only the participants’ characteristics but also the training task design and implementation goal setting (training duration and frequency) are associated with adherence.

Clinical trial registration number

This trial was registered with the University hospital Medical Information Network (UMIN) Clinical Trial Registry (UMIN000038671).

Highlights

• Factors associated with adherence to cognitive training were evaluated.

• Vision difficulty was negatively associated with adherence.

• A larger network of friends was negatively associated with adherence.

• Female sex and higher cognitive function were positively associated with adherence.

• Satisfaction with training tasks and implementation goals was related to adherence.

1. BACKGROUND

Dementia is a global public health challenge. ¹ Despite significant progress in the development of disease‐modifying treatments for dementia, particularly Alzheimer's disease, ² these drugs are not universally applicable to all patients. Moreover, dementia has multifactorial causes. Recently, 14 modifiable risk factors have been identified as contributing to 45% of dementia cases worldwide. ³ Consequently, multidomain intervention trials targeting various mechanisms and risk factors have been conducted globally. ⁴ A key component of these interventions is cognitive training, demonstrating its efficacy in improving cognitive function in studies involving cognitively normal individuals and those with mild cognitive impairment (MCI). ⁵ , ⁶

The Japan‐Multimodal Intervention Trial for the Prevention of Dementia (J‐MINT), an 18‐month randomized controlled trial (RCT), targeted older adults with MCI. ⁷ , ⁸ Its multidomain intervention programs included the management of vascular risk factors, group‐based physical exercise, nutritional counseling, and cognitive training using tablet computers. In the primary analysis, the J‐MINT study did not show significant differences in cognitive changes between the intervention and control groups. ⁸ However, secondary analyses revealed that participants with high cognitive training adherence demonstrated cognitive improvement at 6 months compared with the control group, and this effect was maintained until the end of the trial. ⁸ Similarly, Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) demonstrated that high adherence to interventions, including computer‐based cognitive training, contributed to improved cognitive function compared with the control group. ⁹ However, in both trials, adherence to computer‐based cognitive training was lower than that to exercise and nutritional guidance. ⁸ , ⁹

Various participant characteristics, including age, sex, education level, smoking status, physical activity level, cognitive function, expectations of the intervention program, and experience with computers, are associated with adherence to computer‐based cognitive training. ¹⁰ , ¹¹ , ¹² However, many of these factors are either unmodifiable or difficult to modify. The influence of program‐specific factors—such as the characteristics of the devices used for training, the nature of training tasks, and goals of training implementation, including the time and frequency of the sessions—on cognitive training adherence remains insufficiently understood.

To address this understudied issue, in this post hoc analysis of the J‐MINT study, satisfaction with program‐specific factors and their association with cognitive training adherence in older adults with MCI was investigated.

RESEARCH IN CONTEXT

1. Systematic review: A comprehensive search was conducted on PubMed to identify studies examining factors associated with adherence to computer‐based cognitive training. Participant characteristics, including age, sex, education level, smoking status, physical activity, cognitive function, expectations of the intervention program, and experience with computers, were identified as factors influencing adherence. However, the influence of program‐specific factors, such as device characteristics, task design, and training implementation goals, is insufficiently explored.

2. Interpretation: The results revealed that participants with self‐reported vision difficulties and a larger network of friends were less likely to adhere to cognitive training, whereas those with female sex, higher cognitive function, and greater satisfaction with the training tasks (clarity, difficulty, and enjoyment) and training implementation goals (duration and frequency) were more likely to maintain adherence.

3. Future directions: Training task design and implementation goal setting are modifiable factors that can be optimized in future intervention studies to improve adherence.

2. METHODS

2.1. Study design and study population

Data used for the post hoc analyses were extracted from J‐MINT. The protocol and primary findings of J‐MINT have been published previously. ⁷ , ⁸ J‐MINT was a multicenter RCT conducted over 18 months at five independent institutions in Japan. It enrolled 531 participants 65–85 years of age who had MCI, which was defined as a decline in one or more of four cognitive domains (memory, attention, executive function, and processing speed) by at least one standard deviation (SD) below the age‐ and education‐adjusted reference thresholds.

The participants received a full explanation of the purpose and potential risks of this trial and provided written informed consent before participation. The study was approved by the institutional review boards of all participating institutions.

This post hoc analysis only included participants from the intervention group who completed the trial without missing data on adherence‐related factors.

2.2. Intervention procedures and adherence

The intervention group received multidomain intervention programs, which included the management of vascular risk factors, group‐based physical exercises, nutritional counseling, and cognitive training. ⁷ In the intervention group, participants were provided with an iPad 7th or 8th generations (display, 10.2 in.; weight, 483 or 490 g) and a Fitbit Inspire HR activity monitor. Participants used iPads for cognitive training. In addition, the data collected from the Fitbit were synchronized with an iPad application, allowing participants to self‐monitor physical activities, exercise intensity, and sleep. ⁷

For cognitive training, participants were instructed to engage in cognitive training individually at home or in any preferred location using the Brain HQ (Posit Science Corporation). ¹³ Brain HQ was customized for J‐MINT and consisted of 13 visual exercises targeting cognitive abilities, such as attention, processing speed, memory, mental flexibility, and visuospatial skills. Auditory‐based training tasks were excluded because of considerations for hearing difficulties. Each training session was expected to be last ≈30 min and include several different exercises. Task difficulty was dynamically adjusted using an n‐up/m‐down algorithm, which increases task difficulty following a specific number of correct responses and decreases it after a designated number of incorrect responses. This algorithm ensures that the task adapts to the participant's level of performance. Brain HQ exercises were reported to be beneficial for several cognitive domains, including processing speed and memory, in an RCT conducted specifically for older adults. ¹³ Three intensive training periods were set for the 18‐month intervention period (at 4–6, 10–12, and 16–18 months). During these periods, participants were encouraged to engage in training for at least 30 min per day for ≥4 days per week. In addition, a 10–15 min cognitive training session was incorporated after exercise sessions.

The time (min) that participants spent on training was monitored, and the number of days in which they engaged in the training for at least 30 min was calculated and used as an outcome variable. The adherent cognitive training group included those who engaged in cognitive training lasting ≥30 min per day for >156 days during the 18‐month intervention period. ⁷ The goal was designed to be attainable within the 9‐month intensive training period by following our recommendation of ≥30 min per day for ≥4 days per week.

2.3. Satisfaction with the cognitive training

Upon completion of all interventions, participants’ overall satisfaction with the cognitive training was evaluated using the Client Satisfaction Questionnaire‐8 (CSQ‐8). ¹⁴ , ¹⁵ This questionnaire includes eight items, each rated on a 4‐point Likert scale, ranging from 1 (low satisfaction) to 4 (high satisfaction). The total score is the sum of the individual item scores, ranging from 8 to 32, with higher scores indicating greater satisfaction.

A questionnaire developed specifically for this study was also administered to assess satisfaction with program‐specific factors. This questionnaire included 10 items, covering satisfaction with the device used for cognitive training (size and weight of tablet computer and size of characters on the screen), nature of training tasks (clarity, difficulty, and enjoyment of tasks), training implementation goals (training time per session [≥30 min], frequency per week [≥4], duration of intensive training period [3 months]), and encouragement from intervention staff. Each item was rated on a 5‐point Likert scale, ranging from 1 (low satisfaction) to 5 (high satisfaction).

2.4. Other variables

At baseline, participants’ age, sex, education, living status (living alone or not), smoking status (current smoker or not), vision and hearing difficulties, computer use, physical activity, nutritional status, sleep quality, mood, social participation, and social network were assessed using a self‐reported questionnaire. ⁷ Participants who answered “yes” to the questions, “Do you have a problem with your vision?” and “Do you have a hearing problem?” from the fall risk index were classified as having difficulty in vision and hearing, respectively. ¹⁶ Participants who answered “no” to both questions, “Do you engage in moderate levels of physical exercise or sports aimed at health?” and “Do you engage in low levels of physical exercise aimed at health?” were identified as physically inactive. ¹⁷ The frequency of computer use was assessed, and the participants were divided into two groups based on whether they used a computer at least once a week. Nutritional status was assessed using the Mini‐Nutritional Assessment Short‐Form (MNA‐SF). ¹⁸ The scores ranged from 0 to 14, with higher scores indicating better nutritional status. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). ¹⁹ Its index score ranges from 0 to 21, where a higher score indicates poor sleep quality. Mood was assessed using the 15‐item Geriatric Depression Scale. ²⁰ Social participation was gauged using a questionnaire that assessed eight types of groups. ²¹ The frequency of group participation, defined as at least once or more per month, was used for the analyses. The Lubben Social Network Scale‐6 (LSNS‐6) was used to assess each participant's social network. ²² This scale consists of six items: three related to the network of family (family subscale) and three to friends (friend subscale). The total score ranges from 0 to 30; each subscale ranges from 0 to 15, with higher scores indicating a large social network. Family and friend subscales were included in the analysis. Physical performance was assessed by measuring the usual gait speed >2.4 m, which was measured twice, and the mean value was calculated. ²³ The Mini‐Mental State Examination (MMSE) was used to evaluate global cognitive function. The MMSE score ranges from 0 to 30, with higher scores indicating better cognitive function. ²⁴

2.5. Statistical methods

For categorical data, frequencies and percentages were determined, whereas for continuous variables, means and SDs or medians and interquartile range (IQRs) were calculated. The CSQ‐8 and satisfaction with cognitive training were also described.

To examine differences in baseline characteristics and adherence to cognitive training between participants included and excluded from the analysis, the Kruskal–Wallis test and χ² test were used.

To determine the factors associated with cognitive training adherence, univariate and multiple linear regression analyses were performed. The dependent variable was the number of days the participants engaged in training for ≥30 min. Independent variables, including age, sex, education, living status, smoking status, vision and hearing difficulties, weekly computer use, physical inactivity, gait speed, nutritional status, sleep quality, mood, social participation, social network, cognitive function, and satisfaction with cognitive training (total CSQ‐8 score or satisfaction with program‐specific factors) were forced into the multiple linear regression analysis.

Because the questionnaire for satisfaction with program‐specific factors covers several domains, a factor analysis (principal factor method and Promax rotation) was conducted. From the 10 items, “satisfaction with encouragement from staff,” with a factor loading of <0.4, was excluded. Three factors were identified, which were interpreted as “satisfaction with device characteristics,” “satisfaction with training tasks,” and “satisfaction with training implementation goals” (Table S1). Given the high correlations between the total CSQ‐8 score and these factor scores (Table S2), four separate multiple linear regression models were conducted, each including the total CSQ‐8 score or one of the factor scores. A model that included satisfaction with encouragement from staff was also performed, which was excluded from the factor analysis. All statistical analyses were performed using Stata 17.0 (Stata Corp.). p‐Values of .05 were considered statistically significant.

3. RESULTS

3.1. Participant characteristics

Of the 531 participants enrolled in J‐MINT, 265 were assigned to the intervention group. After excluding 42 participants who immediately withdrew after randomization, 17 who did not complete the trial, and 15 who did not complete the questionnaire on satisfaction with the cognitive training, 191 were enrolled. Participant characteristics are shown in Table 1. The median number of days on which cognitive training was conducted for ≥30 min was 27 (IQR, 3–111) days, with a maximum of 423 days. Of the 191 participants, 38 (19.9%) engaged in ≥30 min of cognitive training per day for ≥156 days.

TABLE 1.

Baseline characteristics, adherence, and satisfaction with cognitive training in participants who completed the trial (n = 191).

Variables	Mean ± SD/median (IQR)/N (%)
Age, years	74.0 ± 4.8
Female sex	95 (49.7)
Education, years	12.6 ± 2.5
Living alone	25 (13.1)
Current smoker	14 (7.3)
Vision difficulty	88 (46.1)
Hearing difficulty	76 (39.8)
Weekly use of computer	82 (42.9)
Usual gait speed, m/s	1.2 ± 0.3
Physical inactivity	45 (23.6)
Mini‐Nutritional Assessment Short‐Form	12.5 ± 1.7
Pittsburgh Sleep Quality Index	4.7 ± 2.9
15‐item Geriatric Depression Scale	3.2 (2.8)
Mini‐Mental State Examination	27.8 ± 1.8
Number of participating social groups	1.4 ± 1.4
Lubben Social Network Scale‐6, Total Score	15.5 ± 5.9
Lubben Social Network Scale‐6, Family Subscale	8.4 ± 3.1
Lubben Social Network Scale‐6, Friend Subscale	7.2 ± 3.7
Cognitive training
Total training time, min	2401.1 (396.1, 8211.9)
Number of days engaged in ≥30 min of cognitive training	27 (3, 111)
≥156 days (≥30 min/day)	38 (19.9)
Client Satisfaction Questionnaire‐8 a
Total mean score	25.1 ± 4.1
1.How would you rate the quality of service you received?	3.2 ± 0.6
2.Did you get the kind of service you wanted?	3.1 ± 0.7
3.To what extent has our program met your needs?	3.1 ± 0.7
4.If a friend were in need of similar help, would you recommend our program to him/her?	3.1 ± 0.5
5.How satisfied are you with the amount of help you received?	3.2 ± 0.6
6.Have the services you received helped you deal more effectively with your problems?	3.1 ± 0.7
7.In an overall, general sense, how satisfied are you with the service you received?	3.2 ± 0.6
8.If you were to seek help again, would you come back to our program?	3.1 ± 0.6
Satisfaction with program‐specific factors b
1.Size of the tablet computer	4.0 ± 0.9
2.Weight of the tablet computer	3.6 ± 1.1
3.Size of the characters on the screen	4.0 ± 0.9
4.Clarity of the training tasks	3.8 ± 0.9
5.Difficulty of the training tasks	3.8 ± 0.9
6.Enjoyment of the training tasks	3.9 ± 0.9
7.Target of training time (≥30 min per session)	3.7 ± 1.0
8.Target of training frequency (≥4 times per week)	3.7 ± 1.1
9.Duration of the intensive intervention period (3 months)	3.7 ± 1.0
10.Encouragement from the intervention staff	4.3 ± 0.9

Abbreviations: IQR, interquartile range; SD, standard deviation.

^a Each Client Satisfaction Questionnaire‐8 item is scored from 1 (low satisfaction) to 4 (high satisfaction), with a total score ranging from 8 to 32.

^b Each item is scored from 1 (low satisfaction) to 5 (high satisfaction).

The comparison of the baseline characteristics and adherence to cognitive training is presented in Table S3. Participants excluded from the analysis (n = 32), which did not include 42 participants who withdrew immediately after randomization, were significantly older (p =  .001), exhibited slower gait speed (p =  .001), and demonstrated lower adherence to cognitive training (p =  .002) than those included in the analysis.

3.2. Satisfaction with the cognitive training

The mean CSQ‐8 score was 25.1. Regarding program‐specific factors of cognitive training, participants reported the highest satisfaction with staff encouragement (4.3/5). They reported the lowest satisfaction for the weight of the tablet (3.6/5), followed by satisfaction with the training implementation goals, including training time (≥30 min per session), frequency (≥4 times per week), and intensive intervention duration (3 months) (3.7/5).

3.3. Adherence‐associated factors

The results of the univariate and multiple linear regression analyses are presented in Table 2. In the univariate analyses, female sex, usual gait speed, MMSE score, and satisfaction with the training implementation goals were positively associated with adherence, whereas vision difficulty and the LSNS‐6 friend subscale were negatively associated with adherence (p <  .05). Although the total CSQ‐8 score and satisfaction with the training tasks were positively correlated with adherence, these associations were not significant (p <  .10). In the multiple regression analyses, female sex, MMSE score, and satisfaction with the training tasks and training implementation goals were positively associated with adherence (p <  .05), whereas vision difficulty and the LSNS‐6 friend subscale were negatively associated with adherence (p < 0.05).

TABLE 2.

Associated factors of adherence to cognitive training (n = 191).

	Univariate analyses		Multivariate analyses
			Model 1		Model 2		Model 3		Model 4
Variables	β	p	β	p	β	p	β	p	β	p
Age	−0.12	0.107	−0.02	0.810	−0.03	0.679	−0.02	0.796	−0.01	0.941
Female sex	0.18	0.011	0.19	0.027	0.19	0.026	0.19	0.025	0.20	0.019
Education	−0.12	0.102	−0.07	0.351	−0.07	0.348	−0.06	0.378	−0.07	0.343
Living alone	−0.08	0.278	−0.09	0.196	−0.09	0.199	−0.10	0.178	−0.08	0.270
Current smoker	−0.09	0.200	−0.01	0.930	−0.02	0.746	−0.02	0.741	−0.02	0.809
Vision difficulty	−0.17	0.019	−0.23	0.002	−0.23	0.002	−0.24	0.001	−0.22	0.003
Hearing difficulty	−0.00	0.973	0.08	0.260	0.09	0.212	0.09	0.230	0.10	0.184
Weekly use of computer	−0.04	0.564	−0.01	0.888	−0.03	0.712	−0.02	0.824	0.00	0.980
Gait speed	0.16	0.028	0.10	0.156	0.09	0.202	0.10	0.151	0.09	0.208
Physical inactivity	−0.09	0.218	−0.08	0.273	−0.08	0.261	−0.09	0.199	−0.08	0.260
MNA‐SF	0.09	0.211	0.12	0.102	0.10	0.166	0.10	0.162	0.11	0.121
PSQI	0.03	0.713	0.05	0.510	0.05	0.494	0.05	0.469	0.06	0.445
15‐item Geriatric Depression Scale	−0.03	0.636	−0.07	0.405	−0.07	0.349	−0.06	0.455	−0.07	0.339
Mini‐Mental State Examination	0.22	0.002	0.20	0.007	0.21	0.005	0.22	0.003	0.22	0.004
Number of participating social groups	−0.06	0.409	−0.06	0.401	−0.07	0.337	−0.07	0.384	−0.08	0.311
LSNS‐6, family subscale	0.01	0.873	0.03	0.712	0.02	0.838	0.03	0.740	0.03	0.681
LSNS‐6, friend subscale	−0.15	0.041	−0.22	0.011	−0.21	0.016	−0.22	0.012	−0.22	0.010
Satisfaction with the cognitive training
Total CSQ‐8 score	0.13	0.076	0.11	0.116
Program‐specific factors
Device characteristics	0.12	0.104			0.11	0.123
Training tasks	0.14	0.055					0.16	0.018
Training implementation goals	0.17	0.018							0.16	0.020

Note: The standard partial regression coefficients are shown. The values in bold indicate significant differences (p <  .05).

Abbreviations: CSQ−8, Client Satisfaction Questionnaire‐8; LSNS‐6, Lubben Social Network Scale‐6; MNA‐SF, Mini‐Nutritional Assessment Short‐Form; PSQI, Pittsburgh Sleep Quality Index.

Encouragement from the intervention staff was not associated with adherence (standard regression coefficient = 0.08, p =  .255).

4. Discussion

Overall, J‐MINT participants reported a high satisfaction level with the cognitive training program. However, the detailed survey indicated relatively lower satisfaction with the weight of the tablets and training implementation goals. Adherence‐associated factors included the participant's characteristics, such as female sex, visual impairment, cognitive function, friend social network, and satisfaction with training tasks and training implementation goals.

Traditionally, cognitive training for individuals with MCI has been conducted in a face‐to‐face format by trained professionals using paper‐and‐pencil methods. With rapid advances in information technology, cognitive training is also now available in computerized formats. Compared with noncomputerized approaches, computerized cognitive training offers several advantages, including cost‐effectiveness, greater accessibility, and the ability to customize training content and difficulty levels. ²⁵ Although the effectiveness of computerized cognitive training on cognition in individuals with MCI has been widely demonstrated, ²⁶ , ²⁷ recent studies have identified challenges such as lower adherence when participants engage independently without professional supervision. ⁸ , ⁹ Adherence is a key factor in the success of cognitive training interventions, ²⁸ and understanding the factors influencing adherence is essential to improving outcomes. This study revealed the factors associated with adherence to tablet‐based cognitive training, focusing not only on participant characteristics but also on their satisfaction with the program‐specific factors.

Lower satisfaction with the implementation goal settings for training time duration and frequency indicates that participants may have felt burdened by high‐frequency or long‐duration goals. Moreover, a higher satisfaction with these implementation goal settings was positively associated with cognitive training adherence. The optimal duration, frequency, and length of training required to maximize the effects of computer‐based cognitive training remain unclear. Meta‐analyses of RCTs targeting individuals with MCI have reported small intervention effects on cognitive function. In the included studies, the session duration ranged from 20 to 100 min per session, with a frequency of 2–5 times per week, and the total intervention duration varied from 2 to 56 weeks, resulting in a total of 4–80 h of training. ²⁶ , ²⁹ Moreover, a meta‐analysis of 12 RCTs analyzed the effects of training dose and indicated that cognitive training was effective regardless of duration (>3 vs ≤3 months), frequency (≥3 vs <3 days per week), or time per session (≥1 vs <1 h per session). ³⁰ However, these were all short‐term studies, lasting <6 months, and little evidence exists regarding the long‐term effects of cognitive training. ³⁰ In the context of dementia prevention, which requires long‐term strategies, appropriate and sustainable goals must be established for the implementation of computer‐based cognitive training.

Satisfaction with the training tasks (clarity, difficulty, and enjoyment) was associated with cognitive training adherence. Brain HQ was not specifically designed for older adults with MCI. Although the difficulty of cognitive training is adjusted according to the participants’ performance, they still need to read or listen to instructions and understand them. In this study, some participants may have found it challenging to understand the instructions, underscoring the need for cognitive training tasks that are easier to comprehend and accompanied by clearer, tailored instructions. During the cognitive training sessions conducted after group‐based exercise classes, some participants were observed teaching each other the task rules. A meta‐analysis of computer‐based cognitive training in cognitively healthy individuals revealed that group‐based training was more effective than home‐based training. ³¹ Accordingly, incorporating group‐based cognitive training, or a hybrid approach that combines group and home‐based training, may facilitate task comprehension, increase enjoyment through social interaction, enhance adherence, and maximize the benefits of cognitive training for individuals with MCI rather than rely solely on home‐based training. Furthermore, to design cognitive training programs that are effective and tailored to the needs of the target population, future studies should incorporate a citizen‐participatory approach from the planning stage, involving participants in discussions to collaboratively develop intervention programs.

Previous studies have reported that adherence to cognitive training varies by participant characteristics, such as age, sex, education level, smoking status, physical activity level, cognitive function, and experience with computers. ¹⁰ , ¹¹ , ¹² In line with the results of a previous study, ¹² female sex was associated with higher adherence in this study. Similar to other large‐scale multidomain intervention trials, ¹⁰ , ¹² cognitive function was identified as a factor associated with adherence to computer‐based cognitive training. In addition, in the present study, self‐reported visual impairment was negatively associated with adherence. Although BrainHQ has auditory‐based training tasks, these were excluded during the planning phase of the trial owing to hearing impairment considerations. Therefore, the BrainHQ customized for the J‐MINT study consisted of visually based training tasks, which may have affected the difficulty for participants with self‐reported visual impairments. In this study, 46.1% of the participants reported visual impairment, highlighting this as a common issue among older adults. In a recent trial, participants with self‐reported vision difficulties did not benefit as much from noncomputerized cognitive training (reasoning training) compared with participants without vision difficulties. ³² This study, along with the present findings, underscores the importance of screening for visual impairments before implementing cognitive training. Accommodations such as adjusting the screen size, font size, or sound volume should also be considered to tailor the task design to individual needs. Furthermore, integrating alternative modalities, such as audio or tactile devices, and employing multisensory methods may enhance accessibility, thereby advancing equity and inclusion in cognitive training interventions. ³³

A larger social network of friends was negatively associated with adherence to cognitive training. Although previous studies have not reported an association between the LSNS‐6 scores and adherence to cognitive training, positive associations with adherence to physical and social activities have been documented. ¹² The reason for this inconsistency is unclear; however, in this study, the inconsistency may be related to the nature of individual cognitive training conducted at home. A larger network of friends could increase the time spent on social activities with friends, potentially leading to time constraints that negatively affect adherence to cognitive training.

This study has several limitations. First, 17 participants dropped out after the initiation of the intervention, and 15 did not respond to the satisfaction questionnaire. Because these participants were significantly older, exhibited slower gait, and demonstrated lower adherence to cognitive training (Table S3), individuals who experienced difficulties with cognitive training or were less satisfied might have been excluded from the analysis. This exclusion may have led to an optimistic overestimation of satisfaction levels. Furthermore, other factors associated with adherence to cognitive training may have been overlooked. Second, although satisfaction with training tasks and implementation goal settings was associated with adherence, satisfaction was determined through a subjective assessment conducted at the end of the intervention. This may introduce limitations in demonstrating causal relationships with actual behavior. Furthermore, the study design did not allow the evaluation of how variations in these factors—such as differences in the specific training tasks or frequency and duration of the training session—affected adherence. Participant preferences, such as whether the frequency or duration of the training program was perceived as too long or too short, were not also assessed. Third, although mood was assessed, other psychological factors such as motivation and study expectations, which have been reported as factors associated with cognitive training adherence, ¹⁰ were not evaluated. In addition, other unmeasured factors may have influenced cognitive training adherence. Fourth, the specific reasons for the participant's engagement or lack thereof in cognitive training were not directly assessed. Qualitative research may offer further insights into this issue. Finally, as the study included older adults with MCI recruited for an RCT, the findings may not be generalized to all older adults with MCI in other settings. Incorporating two J‐MINT Prime studies (UMIN000041887 and UMIN000041938 ³⁴ ), which recruited participants based on different criteria, may contribute to enhancing the generalizability of findings through integrated analyses in the future.

In conclusion, the J‐MINT study showed high overall participant satisfaction with cognitive training. Participants reported high satisfaction with the encouragement provided by staff; however, they expressed relatively lower satisfaction regarding the weight of the tablet computer and training implementation goals (duration and frequency). Vision difficulty and a larger friend social network were negatively associated with adherence, whereas female sex, higher cognitive function, satisfaction with cognitive training tasks (clarity, difficulty, and enjoyment), and training implementation goals were positively related to adherence. These findings indicate that not only participant characteristics but also the training task design and implementation goal settings—both of which have room for improvement—are associated with cognitive training adherence in older adults with MCI.

CONFLICT OF INTEREST STATEMENT

T.Su. received a research fellowship from the Manpei Suzuki Diabetes Foundation and a grant from the Keiko‐Yamasaki Memorial Funds.

The other authors declare no conflicts of interest.

Author disclosures are available in the Supporting Information.

CONSENT STATEMENT

All participants provided written informed consent before participating in the trial.

Supporting information

Supporting Information

Supporting Information

Sugimoto T, Uchida K, Sato K, et al. Factors associated with adherence to tablet‐based cognitive training: J‐MINT study. Alzheimer's Dement. 2025;11:e70062. 10.1002/trc2.70062