Post-stroke cognitive impairment (PSCI) and depression affect over 60% of elderly stroke survivors, severely impairing functional recovery and quality of life. Despite the efficacy of non-pharmacological interventions, evidence on individualized approaches for elderly stroke patients remains limited. This study aims to evaluate the clinical impact of individual reminiscence therapy (RT) on cognitive function, depressive symptoms, and quality of life in elderly stroke survivors.

A single-blinded, parallel, randomized controlled trial will be conducted with 80 elderly stroke patients recruited from two hospitals in Shanghai. Participants will be randomly assigned to an intervention group receiving eight weeks of individual RT (30–45 min weekly) or a control group receiving standard care with a 1:1 ratio. Cognitive function, including Mini-Mental State Examination (MMSE), Boston Naming Test (BNT), Trail Making Test-A (TMT-A), depressive symptoms assessed by the Patient Health Questionnaire-9 (PHQ-9), and quality of life assessed by the Stroke-Specific Quality of Life Scale (Ss-QoL) will be assessed by blinded evaluators at baseline (T0), post-intervention (8 weeks, T1), and 4-week follow-up (12 weeks, T2). The intervention features a tailored RT protocol allowing patients to select topics (e.g., childhood memories, work life) to enhance engagement. Blinded evaluators will ensure measurement objectivity, and intention-to-treat analysis addressed attrition.

This study aims to provide a fresh perspective on the effectiveness of individual RT in enhancing cognitive function, reducing depressive symptoms, and improving the quality of life, among stroke patients. The use of a tailored individual RT program based on an in-depth literature review and conceptual analysis, along with a multidimensional assessment system, differentiates this study from previous ones.

This protocol was registered at the Chinese Clinical Trials.gov (Identifier: ChiCTR2500095471) on January 8, 2025.

Stroke is a global health crisis of immense proportions. As the second leading cause of death worldwide and the third leading cause of disability-related mortality, it has far-reaching implications for public health and healthcare systems [1]. The aging population and the prevalence of chronic conditions such as diabetes further contribute to the rising incidence of stroke [2, 3]. Within the first year following a stroke, up to 60% of patients may experience post-stroke cognitive impairment (PSCI) or post-stroke depression (PSD), both of which significantly affect quality of life [4,5,6,7,8,9]. PSCI can lead to cognitive distortions, diminishing patients’ psychological resilience and exacerbating feelings of isolation, frustration, and disconnection in their interpersonal relationships and society, subsequently increasing the risk of PSD [10, 11]. Conversely, PSD can hinder the rehabilitation process, leading to poor functional recovery, diminished activities of daily living, and decreased social participation [10]. As a result, patients are more likely to avoid complex cognitive tasks, which in turn exacerbates PSCI [11, 12]. This vicious cycle not only intensifies patients’ suffering but also significantly burdens the healthcare system. Therefore, there is an urgent need to improve the early identification and intervention of PSCI and PSD in elderly stroke patients.

In recent years, non-pharmacological treatments have emerged as a significant area of research in healthcare, particularly in addressing the complex issues associated with stroke-related complications [4]. Their appeal lies in their effectiveness, minimal side effects, and cost-efficiency, making them an attractive alternative or adjunct to traditional pharmacological approaches [13, 14]. Among these non-pharmacological interventions, reminiscence therapy (RT) has shown great promise [4, 15, 16]. RT encourages individuals to recall past events, emotions, and thoughts using stimuli like old photographs, memorabilia, and nostalgic songs [17, 18]. The underlying mechanism of RT is based on the activation of brain regions involved in memory and emotion. When patients engage in reminiscence, areas like the hippocampus, which is crucial for memory formation and retrieval, and the amygdala, which plays a key role in emotional processing, are stimulated. This activation promotes the release of neurotransmitters such as dopamine and serotonin. Dopamine is associated with motivation, reward, and cognitive function, while serotonin helps regulate mood [19, 20]. As a result, RT not only improves cognitive function but also alleviates depressive symptoms while enhancing individual well-being and quality of life [18]. Moreover, RT can be effectively implemented in a variety of settings, including community centers, nursing homes, and hospitals [21,22,23]. RT can be delivered by professionals or trained non-professionals, and both approaches have shown positive therapeutic outcomes [24]. This flexibility in implementation, combined with its low cost, makes RT a highly cost-effective intervention. Furthermore, family members can also utilize RT in their daily interactions with patients, which can reduce the long-term rehabilitation need and lower overall healthcare costs [25].

Although RT has demonstrated potential benefits, its application in elderly stroke patients remains limited. Existing research on RT has predominantly centered around neurodegenerative diseases such as Alzheimer’s disease [26, 27]. This means that the evidence bases specifically tailored to the unique needs of elderly stroke patients are scarce. There are several reasons for this limited application. Firstly, the nature of stroke-related cognitive and physical impairments in elderly patients is distinct from those in neurodegenerative diseases [28, 29]. Stroke often leads to sudden-onset deficits in multiple cognitive domains, along with potential physical disabilities, which can pose challenges to the traditional implementation of RT [30]. For example, patients may have difficulty in communicating their memories due to aphasia or may be physically unable to handle the materials used in RT, such as photographs. Secondly, the majority of current individual RT programs are based on general-purpose manuals like “Remembering Yesterday, Caring Today” [27]. However, these manuals do not adequately account for the specific characteristics and requirements of elderly stroke patients. For instance, they may not consider the potential emotional distress that certain memories might trigger in stroke survivors, especially those related to the event of the stroke itself or subsequent life changes.

To address these gaps, our research team conducted an in-depth literature review and conceptual analysis [31]. Through this process, we developed a customized individual RT program for elderly stroke patients. This program is designed to be more specific and applicable to their unique circumstances. Preliminary feasibility verification of this tailored program has been carried out, and although the small-scale nature of the initial study (n = 8) limits the generalizability of the results, it showed varying degrees of improvement in aspects such as cognitive function, depressive mood, attention, and processing speed, as well as quality of life. However, no significant enhancements were observed in memory function and language ability, which may be attributed to the small sample size. Thus, there is a pressing need for larger-scale randomized controlled trials, like the one presented in this study, to comprehensively evaluate the true efficacy of this customized RT program for elderly stroke patients.

Therefore, this randomized controlled trial is designed to fill the existing knowledge gaps regarding the application of individual RT in elderly stroke patients. By comparing the outcomes of an intervention group receiving individual RT and a control group receiving standard care, we aim to comprehensively evaluate the effectiveness of individual RT in enhancing cognitive function, alleviating depressive symptoms, and improving the quality of life among this specific patient population.

To evaluate the effects of individual RT on cognitive function, depressive symptoms, and quality of life in elderly stroke patients. The findings of this study are expected to provide a scientific basis for the development of personalized rehabilitation programs for elderly stroke patients, filling the existing gaps in the application of RT in this patient population and guiding evidence-based clinical decision-making.

A single-blinded, parallel, randomized controlled trial will be executed from January 15, 2025 to August 1, 2026. Following a baseline assessment, participants will be randomly assigned in a 1:1 ratio to either the intervention group or the control group. A blinded evaluator will assess the outcome measures at baseline (week 0, T0), the end of intervention (week 8, T1), and four weeks post-intervention (week 12, T2) to validate the impact on overall cognitive function, various cognitive domains, depressive mood, and quality of life among elderly stroke patients (Fig. 1; Table 1). The study has been registered with the Chinese Clinical Trial Registry under registration number ChiCTR2500095471 and will comply with the SPIRIT (Standard Protocol Items: Recommendations for Intervention Trials) guidelines (Supplementary Material 1).

Flow diagram of the study design

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The study participants consist of elderly stroke patients from the Yangpu Central Hospital and the Second Rehabilitation Hospital in Shanghai. The inclusion criteria include: (1) A confirmed diagnosis of stroke via cranial CT or MRI; (2) Age ≥ 60 years; (3) Mini-Mental State Examination (MMSE) score between 10 and 26 points, indicating mild to moderate cognitive impairment; (4) Stable medical conditions and clear consciousness; (5) Ability to communicate verbally; (6) Recovery phase (≥ 2 weeks post-stroke); and (7) Voluntarily consent to participate by signing an informed consent form. The exclusion criteria are as follows: (1) Illiteracy; (2) Patient Health Questionnaire-9 (PHQ-9) score ≥ 20 points; (3) Significant neuropsychiatric symptoms (e.g., agitation, apathy); (4) Serious comorbidities (such as advanced malignant tumors, severe cardiac insufficiency, liver and kidney failure, etc.) or obvious complications; (5) Severe emotional distress during the intervention; (6) Taking medications that may affect cognition and emotion (such as long-term use of benzodiazepines, unstable doses of antidepressants, etc.); (7) Severe visual or hearing impairments; and (8) Participants in other social psychological intervention studies. Patients will be discontinued from the study if they: (1) Actively request to withdraw from the study; (2) Unreachable during the intervention, making subsequent assessments impossible; (3) Experiences a serious adverse event during the intervention, such as significant health deterioration or an acute medical issue.

The sample size is calculated based on the primary outcome of the MMSE score, drawing on the findings of Pérez-Sáez et al., which indicates a partial η² of 0.076 for the group × time interaction [32]. The effect size for RT’s enhancement of overall cognitive function is calculated to be 0.2867945 using G*power software. ANOVA repeated measures and F-test are chosen as the statistical methods, with a significance level (α) set at 0.05, power (1-β) at 0.8, effect size f at 0.2867945, number of groups at 2, and number of measurements at 3. It is assumed that the correlation between repeated measures is 0, and the non-sphericity correction ε is 0.5. Based on these calculations, the total required sample size is 66 participants, comprising 33 individuals in both the intervention and control groups. Taking into account a dropout rate of 20%, the total sample size required for this study is estimated to be approximately 80 cases, with 40 cases in each group.

Participants will be stratified based on their baseline cognitive function, as assessed by the MMSE scores, into two categories: mild cognitive impairment (MMSE scores 21–26) and moderate cognitive impairment (MMSE scores 10–20). A stratified randomization method will be employed to ensure balanced allocation between the intervention and control groups within each stratum. Randomization is performed using SPSS 25.0 software, which generates a random number sequence to assign participants to either the intervention group (individual reminiscence therapy) or the control group (standard care) in a 1:1 ratio. To ensure allocation concealment, opaque sealed envelopes will be used. Each envelope contains the group assignment, which is only revealed to the researchers immediately before the intervention began. The randomization process will be managed by an independent statistician who is not involved in participant recruitment, data collection, or outcome assessment, thereby minimizing selection bias.

Due to the nature of the intervention, blinding of participants and intervention providers is not feasible. However, to minimize measurement bias, outcome assessments will be conducted by blinded evaluators who are unaware of participants’ group allocations. These evaluators will perform all assessments at three time points: baseline (T0), immediately after the 8-week intervention (T1), and at the 4-week follow-up (T2).

The control group

Patients in the control group will receive standard care, including conventional rehabilitation treatment, medication therapy, and cognitive function training. Standard care was designed to ensure that patients receive adequate support in both physiological and daily life aspects.

The intervention group

The intervention group will undergo individual RT in addition to the standard care provided to the control group. The individual RT sessions will be conducted in quiet, private rooms in the ward to minimize distractions and create a comfortable and safe space for patients to engage in the therapeutic process. Each session lasts between 30 and 45 min and is scheduled once a week for a total duration of 8 weeks.

The content of the RT sessions is structured to achieve specific therapeutic goals. The session structure is described in Table 2.

Week 1 (Introduction and Preparation): The initial session will be dedicated to establishing rapport between the interviewer and the participant. The intervener will introduce the concept of RT and outline its goals. Participants will be encouraged to share their preferences regarding discussion topics and will be prepared for the subsequent sessions.

Weeks 2–7 (Core Reminiscence Sessions): Each session will commence with a brief greeting and a review of the previous session’s content. Participants will select discussion topics from a pre-determined list of 11 themes (my hometown, childhood memories, student life, work and personal life, traditional festivals, leisure and entertainment, changes in fashion, dietary habits, travel experiences, wedding banquets, and parenting experiences) based on their interests. Interveners will facilitate discussions using prompts such as old photographs, music, and personal memorabilia to evoke memories and encourage emotional expression. After each session, the intervener will summarize the discussion, assign homework (e.g., writing a brief account of the session’s topic), and prepare participants for the next session.

Week 8 (Conclusion and Future Outlook): The final session will focus on summarizing the entire RT experience. Participants will be encouraged to reflect on their memories and discuss their expectations for the future. The intervener will provide positive reinforcement and discuss strategies for maintaining cognitive and emotional well-being following the intervention.

All interveners underwent standardized training in RT techniques and will be provided with a detailed intervention manual to ensure consistency across sessions. A qualified rehabilitation nurse will be present during each session to monitor the treatment process, document participant responses, and ensure adherence to the protocol. In cases where participants experienced negative emotional responses, the intervener and nurse evaluated the situation and provided appropriate psychological support. If severe emotional distress occurs, the intervention will be paused, and participants will be referred to a mental health professional.

General social demographic data

Sociodemographic information, including gender, age, date of birth, duration of illness, education level, type of occupation, and marital status, will be collected at baseline using a self-designed questionnaire.

Cognitive function

The overall cognitive function of the patients will be assessed using the MMSE, a widely validated scale developed by Folstein et al. in 1975 [33]. The Chinese version was subsequently translated by Katzman et al. in 1988 [34], demonstrating a Cronbach’s alpha value of 0.833 [35]. The MMSE comprises 11 items assessing five cognitive domains. It includes orientation (time and place), memory (immediate recall and short-term memory), attention and calculation (serial subtraction or spelling backward), language (naming, repetition, reading comprehension, writing, and copying), and executive function (three-step commands). The maximum score is 30, with a higher score indicating better overall cognitive function. Scores are categorized as follows: ≥24 indicates normal cognition, 18–23 indicates mild cognitive impairment, 10–17 indicates moderate cognitive impairment, and < 10 indicates severe cognitive impairment.

Depression

The patient’s depression will be assessed using the PHQ-9, which was developed by Kroenke et al. [36]. It has been translated into Chinese, demonstrating a Cronbach’s alpha and correlation coefficient of 0.86, indicating strong reliability and validity [37]. This scale includes 9 items with a total score of 27. Scores ranging from 0 to 4 suggest no depression, 5 to 9 indicate mild depression, 10 to 14 denote moderate depression, 15 to 19 suggest moderate to severe depression, and 20 to 27 indicate severe depression.

Language ability

This study will utilize the Boston Naming Test (BNT) to assess language function [38]. The test has been translated into Chinese, and its validity has been confirmed within the Chinese population, exhibiting a Cronbach’s α value of 0.94 [39]. The BNT consists of 30 images, and during the Chinese adaptation, the first step involves spontaneous naming, the second involves semantic cue naming, and the third has been modified to include multiple-choice questions. The maximum score is 30, with higher scores indicating better language ability.

Attention and processing speed

The Trail Making Test A (TMT-A) will be used to assess attention and processing speed. This test was standardized by Reitan [40] and subsequently applied within the Chinese population, demonstrating strong reliability and validity [41]. TMT-A is one of the most widely used neuropsychological tests globally. In TMT-A, participants are asked to connect numbers from 1 to 25 in sequential order as quickly as possible. The time taken to complete the task is recorded, with shorter times indicating better attention and processing speed.

Quality of life

Quality of life will be assessed using the Stroke-Specific Quality of Life Scale (Ss-QoL), a 49-item scale specifically designed for stroke patients [42]. The Chinese version exhibits strong reliability, validity, and sensitivity, with a Cronbach’s α value of 0.76 [43]. The Ss-QoL assesses 12 domains, including energy, family roles, language, mobility, mood, personality, self-care, social roles, thinking, upper extremity function, vision, and work/productivity. Each item is scored on a 5-point Likert scale, with a total score ranging from 49 to 245. Higher scores indicate a better quality of life.

To ensure optimal adherence to the intervention protocol, researchers will proactively contact participants to schedule intervention sessions and send timely reminders the day before and on the day of the intervention to ensure adherence. Additionally, participants will receive a gift upon enrollment and after the final follow-up to enhance their motivation and engagement throughout the study.

Data collection will commence following the acquisition of informed consent from participants (Supplementary Material 2). General information about the patients will be gathered, and appropriate scales will be utilized for assessments conducted before and after the intervention using a self-designed survey. Assessments will be conducted before and after the intervention using a suite of well-established scales, including the MMSE, BNT, TMT, PHQ-9, and Ss-QoL. These instruments have been widely utilized both domestically and internationally, exhibiting high reliability and validity. Data will be collected face-to-face by data collectors with participants at baseline, post-intervention, and during follow-ups to ensure the completeness and accuracy of the data. During the inquiry or explanation process, data collectors will refrain from guiding or implying answers to ensure precision. After the completion of the questionnaires and scales, investigators will meticulously review and verify each form on-site for any omissions or evident logical errors, thereby safeguarding the completeness and accuracy of the data. The interveners have undergone systematic training in RT-related skills and will focus on guiding patients through relevant topic discussions during the intervention, avoiding the intermingling of topics. Each intervention session will include a rehabilitation nurse to supervise, record, and evaluate the intervention process, ensuring adherence to the treatment protocol. Under the guidance of statistical professionals, tasks such as database establishment, data entry, and statistical analysis will be executed. Epidata software will facilitate data entry in a double-entry format, and consistency checks will be performed between the two databases; any inconsistencies will be verified against the original questionnaires. Following these consistency checks, analysis will be conducted. All source data, including questionnaires, interview records, and clinical evaluations, will be stored in both electronic and paper formats. Electronic data will be housed in a password-protected database accessible only to authorized research team members, while paper documents will be secured in locked filing cabinets. Furthermore, all data will be regularly backed up to prevent accidental loss.

Statistical analyses of the collected data will be performed using SPSS 25.0 software. The statistical methods employed include descriptive analysis for general data, frequency tables, percentages, or composition ratios for qualitative data, and mean ± standard deviation for quantitative data conforming to a normal distribution. For data that does not meet normality, the interquartile range will be utilized. Intergroup comparisons will be conducted using chi-square tests for categorical data, t-tests for normally distributed measurement data, and the Wilcoxon rank-sum test for non-normally distributed data. A mixed design comprising 2 (intervention group and control group) × 3 (T0, T1, and T2) is employed to conduct a repeated measures analysis of variance aimed at investigating the relationships between individual RT, overall cognitive function, specific dimensions of cognitive function, depression, and quality of life. All statistical analyses will be conducted using a two-tailed test with a significance level set at α = 0.05; differences will be considered statistically significant when P < 0.05. In cases of loss to follow-up during the trial, intention-to-treat (ITT) analysis was utilized to ensure the reliability and validity of the study results.

This study will comply with the Helsinki Declaration and Clinical Research Ethics Guidelines. The study protocol has been approved by the Ethics Committee of Yangpu Hospital of Tongji University (LL-2024-KYHZ-006) and Shanghai Second Rehabilitation Hospital (2024-27-01).

As the global population continues to age, cognitive and emotional health issues among elderly stroke patients have become increasingly prominent, posing significant challenges to rehabilitation and quality of life. Recent years have seen individual RT widely recognized as an effective intervention for enhancing cognitive function and addressing emotional problems in this vulnerable population [32, 44, 45]. This therapeutic approach facilitates the rebuilding of self-esteem and the enhancement of social connections by encouraging patients to revisit personal memories, effectively addressing the psychological and cognitive challenges experienced during rehabilitation. However, despite its potential benefits, the application of individual RT among elderly stroke patients remains limited and lacks specificity [46]. This study aims to conduct a randomized controlled trial to evaluate the impact of individual RT on cognitive abilities, depression levels, and quality of life in elderly stroke patients, thereby elucidating its significance in improving patient rehabilitation and providing evidence-based support for clinical practice.

Research indicates that reminiscence activates brain regions associated with memory, emotion, and reward, promoting the release of neurotransmitters and enhancing the connectivity of neural networks. This process enhances individual self-continuity, social connectedness, and positive emotions while simultaneously alleviating negative emotions and fostering psychological resilience [47, 48]. Elderly individuals often demonstrate superior ability in recalling past experiences, and this reminiscence can provide emotional support alongside promoting psychological satisfaction and fulfillment [44, 48]. In studies addressing cognitive impairment and depression among the elderly, individual RT exhibits distinct advantages. Cochrane systematic reviews revealed that individual RT was more effective than group RT and is particularly applicable to populations with cognitive impairments [26]. Individual RT emphasizes interaction between the patient and the intervention provider, tailoring treatment content according to patient preferences [49]. This approach aligns with the increasing emphasis on personalized care and patient-centered treatment in geriatric healthcare. However, the application of individual RT among elderly stroke patients remains limited and lacks specificity. Therefore, our study aims to address these gaps by introducing a tailored individual RT program specifically designed for elderly stroke patients, incorporating personalized reminiscence themes and flexible implementation strategies to enhance its applicability and effectiveness.

Recent studies have demonstrated the potential of RT to improve cognitive function and alleviate depression in elderly stroke patients. For instance, a randomized controlled trial by Cheng et al. (2021) reported that RT significantly reduced cognitive impairment, anxiety, and depression in acute ischemic stroke patients [50]. Similarly, Yu et al. (2023) found that RT improved cognitive function and depression in recurrent acute ischemic stroke patients. These findings suggest that RT can be an effective intervention for PSCI and PSD [51]. However, the efficacy of individual RT compared to group RT remains a topic of debate. While some studies indicate that individual RT may be more effective for certain outcomes, such as depression remission [32], others highlight the benefits of group RT in promoting social interaction and support [52, 53]. Our study aims to further explore the effects of individual RT tailored specifically for elderly stroke patients, addressing the unique challenges posed by stroke-related impairments.

Quality of Life (QoL) is a critical outcome measure in stroke rehabilitation, and recent evidence supports the role of RT in enhancing QoL among elderly stroke survivors. A systematic review highlighted that RT can significantly improve life satisfaction and quality of life in community-dwelling older adults [23]. This aligns with our study’s objective to evaluate the impact of individual RT on stroke-specific quality of life using the Ss-QoL. Our tailored RT program incorporates personalized reminiscence themes and flexible implementation strategies, allowing patients to select topics that resonate with their experiences and preferences. This approach not only enhances engagement but also addresses the unique emotional and cognitive needs of elderly stroke patients. By focusing on individualized care, our study aims to provide robust evidence for the integration of RT into clinical practice, supporting the development of personalized rehabilitation programs that improve both cognitive function and emotional well-being.

Despite meticulous planning, this research contains certain limitations. For instance, the study is geographically confined to Shanghai, which may compromise the representativeness of the sample. Additionally, as a single-blind randomized controlled trial, implementing blinding for research participants and intervention providers poses challenges that may introduce potential biases.

In summary, this study seeks to explore the applicability and potential effects of individual RT in enhancing cognitive functioning, alleviating depressive emotions, and improving the quality of life among elderly stroke patients. This research aims to provide evidence-based support for both clinical practice and family care, effectively addressing patients’ cognitive and emotional challenges. Furthermore, the elderly patient group participating in this study is anticipated to serve as a critical driving force in advancing cognitive rehabilitation and emotional management initiatives across a broader elderly population. Our findings not only contribute to enriching the theoretical framework of psychological interventions for stroke but may also offer significant insights for updating existing evidence-based guidelines and policies related to post-stroke cognitive impairment care. Looking ahead, we aspire to investigate the neurobiological mechanisms underlying RT’s impact on cognition and emotions through the integration of brain science techniques such as functional near-infrared spectroscopy (fNIRS), thereby providing more comprehensive and scientifically grounded intervention strategies for the recovery of elderly stroke patients. Additionally, exploring the long-term effects of RT and its potential application in other neurorehabilitation contexts may further enhance its clinical relevance. Ultimately, the goal is to improve the recovery and quality of life for elderly stroke patients through innovative and evidence-based interventions.

This protocol was registered at the Chinese Clinical Trials.gov (Identifier: ChiCTR2500095471) on January 8, 2025. Recruitment began on January 15, 2025, and is expected to be completed on August 1, 2026.

MMSE:

Mini-Mental State Examination

PHQ-9:

Patient Health Questionnaire-9

BNT:

Boston Naming Test

TMT-A:

Trail Making Test-A

Ss-QoL:

Stroke-Specific Quality of Life Scale

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Author notes

CW, XL, JJ and SW designed the study, SW, MH and YX wrote the manuscript. SW, YC and XL developed the details of reminiscence therapy. SW, MH, LL and XL recruited the patients and refined the protocol. CW, KL, LD critically revised the manuscript. All authors approved the final version.

Correspondence to Xuemin Li or Caiqin Wu.

The studies involving human participants were reviewed and approved by the Ethics Committees of Yangpu Hospital of Tongji University (LL-2024-KYHZ-006) and Shanghai Second Rehabilitation Hospital (2024-27-01), Shanghai, China. Participants will receive comprehensive study information before signing the informed consent form, with assurances that their data will be handled with confidentiality and anonymity.

Not applicable.

The authors declare no competing interests.

An unauthorized version of the Chinese MMSE was used by the study team without permission; this has now been rectified with PAR. The MMSE is a copyrighted instrument and may not be used or reproduced in whole or in part, in any form or language, or by any means without written permission of PAR (www.parinc.com).

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