The objective of this study is to investigate psychometric properties of dual-task walking assessments and compare effects of three types of dual-task balance interventions on dual-task walking for stroke patients.

English Synopsis

I. Title of Study:

Immediate and retained effects of three types of dual-task interventions on dual-task walking performance of stroke patients: psychometric study and randomized controlled trial

II. Study Objectives:

The objective of this study is to investigate psychometric properties of dual-task walking assessments and compare effects of three types of dual-task balance interventions on dual-task walking for stroke patients. Specifically, we will investigate psychometric properties (i.e. reliability, validity, and responsiveness) of dual-task walking assessments with various levels of difficulty for stroke individuals (Aim 1). The second aim of this study is to compare the immediate and retained effects of combined motor and cognitive dual-task training (MCDTT), motor dual-task training (MDTT), and cognitive dual-task training (CDTT) on dual-task gait and cognitive performance after stroke (Aim 2). The third aim of this study is to elucidate the changed CMI pattern of stroke patients after dual-task interventions (Aim 3).

III. Study Design A metric analysis and comparative efficacy research will be conducted at medical center(s). Sixty ambulatory stroke patients will receive dual-task walking assessments twice at pretreatment with a 1-week interval for test-retest assessment and investigation of the reliability and validity of outcome measures. The primary outcome measure of the six dual-task walking assessments will include two types of walking conditions (walking at preferred speed and fast speed) and simultaneously perform three cognitive tasks (Serial Three Subtractions, Stroop, and Auditory Stroop tasks). These three cognitive tasks represent different domains of cognitive function: working memory and executive function. Concurrent validity will be studied to validate the dual-task walking measures with each other and with the item 14 of the mini-Balance Evaluation Systems test (Mini-BESTest) and dual-task Timed-up-and-Go test (dual-TUG) obtain concurrently for assessing dual-task ability. In addition, we will compare dual-task walking performance between fallers and non-fallers to examine discriminant validity of dual-task assessments.

A comparative efficacy research is a single-blind, randomized controlled trial. Sixty stroke patients will be randomized to MCDTT or MDTT or CDTT. All three groups will receive dual-task interventions at progressively increasing task difficulty 3 times a week for 4 weeks. The MCDTT group will undertake sitting to standing, standing balance, and treadmill walking training while concurrently perform motor and cognitive tasks. The MDTT and the CDTT groups will train the same set of sitting to standing, standing balance, and walking activities as the MCDTT group while simultaneously performing only motor or cognitive task, respectively. During each session, all participants will receive the instruction of a variable priority to practice shifting attention between tasks by spending half of the training attention focus on the balance task, and half focus on the secondary cognitive or motor tasks. A blinded assessor will administer three assessments All participants will be examined gait and cognitive performance under single-task (walking only, cognitive tasks only) and dual-task conditions (walking while performing 3 cognitive tasks) at two baselines, post intervention, and 1-month follow-up. The primary outcome measure of gait and cognition is gait speed and composite score of accuracy and reaction time of the cognitive tasks under single- and dual-task conditions. The secondary outcome measures will be the Berg Balance Scale, Mini-BESTest, dual-TUG, Functional Gait Assessment, Activity-specific Balance Confidence Scale, Chair Stand Test, Stroke Impact Scale, and Patient Global Impression of Change. Repeated measure ANOVA will be used to compare measurements at baseline, after training, and follow-up among the groups.

Number of Planned Patients: 60 stroke patients Duration of the Study: 2018/08/01～2021/07/31

Inclusion Criteria:

• (1) first-ever stroke with onset duration more than 3 months
• (2) able to walk 10 m
• (3) no severe vision, hearing, and language problems.

Exclusion Criteria:

• orthopedic and other neurological disorders that affect walking
• other treatments that could influence the effects of the interventions (e.g., recent Botulin toxin treatment of the lower extremity)
• moderate or severe cognitive impairments (score < 24 on Mini-Mental State Examination)
• severe uncorrected visual deficits.