Tai Ji Quan and Cognitive Function in Older Adults With Mild Cognitive Impairment

The Montreal Cognitive Assessment scale measures change in global cognitive function from baseline to 6 months. The scale scores range from 0 to 30 points, with higher scores indicating better cognitive functioning.

Assessing change in dual-task ability (measured in seconds) from baseline to 6 months. Change will be assessed via an Instrumental Timed Up&Go (iTUG) gait performance (APDM, Inc.) in which the participant is asked to stand up from a chair, walk a 6-m walkway at normal pace (3 m toward a line, turn, and 3 m toward the chair), turn around, and sit down on the chair, with no cognitive task (single-task walking). The participant is then asked to perform the same procedure with a concurrent cognitive task (counting backward by 3s, starting with an odd number, e.g., 81).12 The total walking duration (in seconds) during both 6-meter walks, at normal pace, will be recorded. Lower duration indicates a better outcome.

The Clinical Dementia Rating Scale measures change in cognitive decline from baseline to 6 months. The scale measures six domains of cognitive and functional performance. Scores range from 0 to 3 points in each domain, with a score of 0 indicating no impairment, while a score of 3 signifying severe impairment. Scores from all domains have been averaged to compute the total score reported. In this trial, lower scores indicate less severity in cognitive decline (i.e., improvement from intervention).

Change in domain-specific cognitive function - executive function (measured in seconds) from baseline to 24 weeks. Trail Making Test assesses attention and executive function. In this test, the participant connects numbers and letters in an alternating progressive sequence, 1 to A, 2 to B, 3 to C, and so on. For parts A and B, scoring is expressed in terms of the time (in seconds) to completion. Lower scores indicate higher executive functioning.

The 4-Stage Balance Test measures change, from baseline to 6 months, in standing four positions balance. Participants attempt to hold four progressively challenging standing positions. The test ends if a position cannot be held for 10 seconds. The number of positions successfully completed is recorded and awarded one point (0-4), with higher score values indicating better balance.

The Backward Digit Span test assesses memory. The participant is verbally presented with a series of digits (e.g., 6, 2, 9, 7) at a rate of one digit per second and is required to repeat them verbatim. If the participant succeeds, he/she is given a longer list (e.g., 5, 3, 8, 1, 6). The number of digits increases by one until the participant consecutively fails two trials of the same digit span length. The length of the longest list a person can remember is that person's digit span. In this test, the participant is required to repeat the digits in reverse. The participant receives 1 point for each correct answer. The Backward Digit Span test scores range from 0 to 32, with higher scores indicating better memory.

The Verbal Fluency Test assesses verbal fluency and executive function of cognitive function. The participant is asked to generate the names of as many animals as possible in 60 seconds. High scores (i.e., more animals names generated) in this measure indicate better performance (i.e., better verbal fluency and executive function).

The Timed up and go (TUG) measure is recorded in seconds (the time taken by an individual to stand up from a standard armless chair, walk a distance of 3 meters, turn, walk back to the chair, and sit down). Lower scores indicate better performance.

The 30-Second Chair Stands Test is used to measure change from baseline to 6 months in physical performance. The Test involves repeatedly standing up from and sitting down in a chair as many times as possible within 30 seconds, with high (count) scores indicating better performance (i.e., leg strength).

The Forward Digit Span test measures attention/concentration (in points) with high scores indicating better attention. The participant is verbally presented with a series of digits (e.g., 6, 2, 9, 7) at a rate of one digit per second and is required to repeat them verbatim. If the participant succeeds, he/she is given a longer list (e.g., 5, 3, 8, 1, 6). The number of digits increases by one until the participant consecutively fails two trials of the same digit span length. The length of the longest list a person can remember is that person's digit span.

Change in sleep quality from baseline to 24 weeks. The Pittsburgh Sleep Quality Index (PSQI) includes seven indices: subjective quality, latency (i.e., time needed to fall asleep), duration (i.e., number of hours of actual sleep per night), efficiency (i.e., total sleep time divided by time in bed, converted to a score of 0-3), sleep disturbances (e.g., waking up in the middle of the night and the like), use of sleeping medication, and daytime dysfunction (e.g., having difficulty staying awake during the day). Each of the component scores ranges from 0 to 3, with the PSQI global score ranging from 0 to 21 points, with higher scores indicating poorer sleep quality.

Change in depression from baseline to 24 weeks. The Geriatric Depression Scale (GDS) score ranges from 0 to 15 with higher scores indicated increased depression symptoms and scores higher than 5 indicative of depression.

The Activity and Movement Confidence Scales measure a person's movement confidence. In this study it assesses change in activity and movement confidence from baseline to 24 weeks. The total score ranges from 0 to 100 with higher scores indicating higher confidence.

The Quality of Life - EuroQol. scale assesses quality of life. Change in quality of life from baseline to 24 weeks. The EQ-5D-3L version will be used that comprises five dimensions: mobility, self-care, usual activities, pain/discomfort and anxiety/depression. The scores of EQ-5D-3L will be averaged to generate a single utility value ranging from 1.00 for the "best health" state to -0.594 for the "worst health" state, where a score of 0 is indicative of death, and scores less than 0 are considered as "worse than death." Participants who die during the trial period will be registered as 0 in utility terms for the assessment period from when the death occurred.

The International Physical Activity Questionnaire (IPAQ) measures the level of moderate and vigorous physical activity (MVPA) (measured in minutes) with high scores indicating high level of physical activity. This measure asks participants to report how often (measured in days) and how much time (in minutes) over the previous week they participated in physical activity or exercise of any moderate (ex. gardening, cleaning, etc.) or vigorous (ex. heavy lifting, jogging/running or fast bicycling, etc.) intensity that lasted at least 10 minutes at a time. The activities to be asked during the post-intervention follow-up (at 6 months) will not include the time spent in attending the assigned exercise programs in the study. Total weekly duration of MVPA, measured in minutes, are calculated by multiplying frequency and duration (vigorous activity weighted by 2) to form a total weighted amount of MVPA min/week.

The Everyday Cognition Scale measures change from baseline to 6 months in everyday cognitive function. Sub scale scores will be averaged to create a total score. Total scores range 1 to 4, with higher scores indicating better everyday cognitive function.