Exploring the Effectiveness of Incorporated Versus Additional Dual-Task Training Program in Community Older Adults

Primary outcomes

1. Change scores of Montreal Cognitive Assessment

   Time frame: Baseline, posttest(after completing the intervention,often baseline after 4 week) , Midterm(2 week after completing intervention) , 3 -month after completing intervention

   The Montreal Cognitive Assessment (MoCA) will be used to assess general cognitive functions. It examines several cognitive domains with a total score of 30 and higher values indicate better cognitive functions. The MoCA has been shown to be a valid and promising tool to evaluate the global cognitive function in patients with stroke. Minimum: 0 (worst performance) Maximum: 30 (best performance) The psychometric properties of MoCA are good to excellent for patients with cerebrovascular diseases.

2. Change scores of Word List (WL) subtest from the Chinese version of the Wechsler Memory Scale-Third Edition (WMS-III)

   Time frame: Before the intervention arms within a week, within a week after the waiting period ends, and within a week after the last treatment .

   The Word List (WL) subtest from the Chinese version of the Wechsler Memory Scale-Third Edition (WMS-III) is a standardized and reliable measure of working memory . This study utilized WL Part I (WL-I), where participants are verbally presented with a list of 12 unrelated words over four trials and asked to recall the words immediately after each trial. Raw scores represent the total number of correct recalls across trials and are converted into age-adjusted scaled scores. Higher scores reflect better memory performance. The WL-WMS has demonstrated strong internal consistency (Cronbach's alpha > 0.80) and high construct validity across diverse populations .

3. Change scores of Stroop Color and Word Test (SCWT)

   Time frame: Baseline, posttest(after completing the intervention,often baseline after 4 week) , Midterm(2 week after completing intervention) , 3 -month after completing intervention

   The Stroop Color and Word Test (SCWT) was used to examine inhibitory control . The primary measure used was the time difference (in seconds) between the congruent and incongruent conditions. Smaller differences indicate better inhibitory control. The Stroop test has shown high test-retest reliability (ranging between 0.70 and 0.91) and convergent validity with other executive function measures .

4. Change scores of Digit Symbol Substitution Test (DSST)

   Time frame: Baseline, posttest(after completing the intervention,often baseline after 4 week) , Midterm(2 week after completing intervention) , 3 -month after completing intervention

   The Digit Symbol Substitution Test (DSST), a subtest of Wechsler Adult Intelligence Scale(WAIS), was used to assess information processing speed. It is sensitive to detect cognitive impairment and changes in cognitive function . Participants are required to match symbols to corresponding numbers and copy the symbols into designated spaces within 120 seconds. The DSST score is the total number of correct symbols, with higher scores indicating better information processing speed. The DSST demonstrates excellent test-retest reliability (r = 0.89) and good concurrent validity with other cognitive processing measures .

5. Change scores of Timed Up and Go (TUG)

   Time frame: Baseline, posttest(after completing the intervention,often baseline after 4 week) , Midterm(2 week after completing intervention) , 3 -month after completing intervention

   The TUG is a widely used screening tool to assess mobility and balance in community-dwelling older adults and to identify individuals at risk of falling ). Faster completion times indicate better functional mobility. The TUG demonstrates excellent inter-rater and test-retest reliability (ICC > 0.90) and good predictive validity regarding fall risk .

6. Change scores of Community Integration Questionnaire (CIQ)

   Time frame: Baseline, posttest(after completing the intervention,often baseline after 4 week) , Midterm(2 week after completing intervention) , 3 -month after completing intervention

   The Community Integration Questionnaire (CIQ) assesses individuals' integration into social networks and engagement in productive activities such as employment, education, or volunteer work . Higher scores indicate great level of social integration. It has shown good internal consistency (Cronbach's alpha approximately 0.70-0.80) and acceptable construct validity .

7. Change scores of Lawton Instrumental Activities of Daily Living(L-IADL)

   Time frame: Baseline, posttest(after completing the intervention,often baseline after 4 week) , Midterm(2 week after completing intervention) , 3 -month after completing intervention

   The Lawton IADL Scale is a valid tool designed to evaluate the ability to perform tasks and detect early functional decline. It is a reliable and valid tool commonly used for evaluating older adults with cognitive impairment . The scale measures tasks such as using a telephone, shopping, food preparation, housekeeping, laundry, transportation, medication management, and financial management. Higher scores indicate greater independence in IADLs.

8. Change scores of Box and Block Test (BBT)

   Time frame: Baseline, posttest(after completing the intervention,often baseline after 4 week) , Midterm(2 week after completing intervention) , 3 -month after completing intervention

   The Box and Block Test (BBT) assesses gross manual dexterity . Participants move wooden blocks from one box compartment to another within 60 seconds. The number of blocks that are moved from one compartment to another compartment is recorded. The more blocks means the better gross manual dexterity. The BBT shows excellent test-retest reliability (ICC = 0.95) and strong validity for manual dexterity evaluation in older adults and clinical populations .

9. Change scores of Serial Sevens Test (SST)

   Time frame: Baseline, posttest(after completing the intervention,often baseline after 4 week) , Midterm(2 week after completing intervention) , 3 -month after completing intervention

   The Serial Sevens Test (SST) evaluates working memory via serial subtraction by sevens . Correct and incorrect responses to SST are recorded, and the corrected number which is the difference between correct and incorrect responses is calculated. The more corrected numbers means the better working memory. While specific reliability data is limited, SST performance correlates moderately to strongly with other working memory and attention tasks, suggesting acceptable construct validity .

10. Change scores of Frequency Discrimination (FD)

    Time frame: Baseline, posttest(after completing the intervention,often baseline after 4 week) , Midterm(2 week after completing intervention) , 3 -month after completing intervention

    The frequency discrimination (FD) assesses sustained attention by requiring participants to distinguish between high and low auditory pitches. Participants discriminated between high (1000 Hz) and low (500 Hz) pitches and reported their answers in 18 trials conducted in 60 seconds. There was a total of 18 trials conducted in 60 s. Specifically, there were nine trials each for high- and low-pitch sounds, presented in random order with intervals of 1 to 4 seconds. Correct and incorrect responses to FD are recorded, and the corrected number which is the difference between correct and incorrect responses is calculated. Higher scores indicate better sustained attention. The task shows acceptable test-retest reliability and construct validity within auditory attention paradigms .