Virtual Reality Attention Training in Stroke Patients
试验速览
- 阶段
- 不适用
- 状态
- 终止
- 发起方
- KU Leuven
- 入组人数
- 6
- 试验地点
- 4
- 主要终点
- Change in the Posner reaction times
研究概览
简要总结
Hemispatial neglect is a post-stroke condition in which patients fail to detect stimuli presented on the side of space opposite to the damaged brain hemisphere (contralesional space). To date, there is no established effective treatment for this condition. A virtual reality (VR) behavioral training for the attention deficits characteristic of patients with hemispatial neglect was developed. Patients are stimulated in the visual and auditory modality to orient towards the contralesional side and are rewarded for detecting targets on this side in this training. In the current study the researchers aim to answer two main questions: 1) how feasible is a VR game-based intervention in stroke patients? and 2) what is the efficacy of the virtual reality game-based intervention in reducing the attention deficits characteristic of hemispatial neglect? To answer these questions a randomized partially double-blind placebo-controlled crossover study will be conducted. Two within-subject conditions will be compared: in the active condition patients will play a VR game in which multisensory stimulation is progressively presented in the neglected region (the location where previously presented targets were missed by the patient) and in the placebo condition patients will play a VR game in which the stimulation is presented in the center of of the VR environment. Neglect symptoms will be measured on a two-daily basis to establish the trend of symptom recovery through time. The hypothesis states that symptoms will recover more quickly when patients receive the active version of the VR intervention compared to the placebo version of the VR intervention.
详细描述
SAMPLE SIZE ESTIMATION:
Power analysis was performed with the SIMR package in R which estimates power for generalized linear mixed models using Monte Carlo simulations. The main analysis will compare the evolution through time of the primary outcome variable between the two within-subject conditions placebo and active intervention. Power was estimated as a function of the number of patients who complete the entire study protocol and as a function of the number of assessment moments per patient. In addition, the power analysis was run under the assumption that the measurement error (residual variance) would be equal to 0.20 SDs. The latter implies that the outcome variable must have a reliability of at least .80. The power analysis revealed that 8 patients need to complete the entire study protocol (per-protocol sample size) - when the study protocol involves a 1-day in-between assessment schedule - to detect a moderate effect size (SD = 0.5) with a type I error rate of 1% and a power of 80%. Thus, for each counterbalancing group a minimum of 4 patients is needed. Assuming that 50% of all patients allocated to a counterbalancing group drop-out at some time point during the study, a total of 16 patients will be recruited to obtain a large enough per-protocol sample size.
MISSING DATA HANDLING:
Missing data can occur when patients do not take part in one or more visits throughout the study protocol (non-monotonous missing data) or when patients drop-out from the study and there is no data available of a patient after drop-out (monotonous missing data). The frequency of occurrence of these two types of missing data will be reported. If inconsistent data occurs on an individual level this will not be considered to be missing data. Out-of-range results for most behavioral outcomes are not likely to occur because computerized assessment tasks guarantee accurate data acquisition. For the behavioral observation scale the inter-rater reliability will be evaluated as a quality check. If the inter-rater reliability across all assessments made in the context of the study is lower than .70 this measure will be reported as insufficiently reliable to be used as a meaningful outcome variable. Only eye tracking data that was sufficiently accurately measured will be considered to be used as an outcome measure. Meaning that, if eye tracker calibration is not good to excellent according to the software delivered with the eye tracker after 5 repeated calibrations the eye tracking data for that assessment will be considered as missing data.
STATISTICAL ANALYSIS:
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Treatment
- 盲法
- Double (Participant, Outcomes Assessor)
盲法说明
Patients are not explicitly explained that a placebo and active version of the intervention will be compared, which makes it more likely for patients not to be aware of the treatment conditions. However they may notice a difference between the two interventions when they switch over from the first to the second intervention condition. In addition, the clinician who will administer the intervention to the patient on a daily basis cannot be blinded to the specific intervention that is administered to the patient, because the clinician will remain present during the intervention to guide the patient through the intervention. However, the clinicians that will perform the evaluation of symptoms using the tasks that are most sensitive to observer bias will be blinded to the treatment condition that is currently applied to the patient to avoid that the measurement of outcome is affected by observer bias.
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •They are above 18 years.
- •They have had a stroke.
排除标准
- •They or their legal representative are unable to provide informed consent.
- •They have a severe comorbid psychiatric (E.g. psychotic symptoms) disorder.
- •They have a premorbid neurodegenerative disease (E.g. Alzheimer's dementia, vascular dementia).
- •They have severe written language comprehension deficits.
- •They have a medical implant, such as a cochlear implant or a pacemaker.
- •They have a severe visual or auditory impairment that cannot be corrected for by wearing glasses or a hearing aid while wearing the Oculus Rift headset.
- •They are unable to concentrate on a task for more than 15 minutes or are unable to complete a task according to simple task instructions.
- •They have a history of epileptic seizures.
- •They do not show signs of a spatial asymmetry in performance on a battery of screening tasks.
- •The expected discharge of patients is in a period shorter than 7 weeks.
结局指标
主要结局
Change in the Posner reaction times
时间窗: The primary outcome variable is measured at 8 timepoints: First timepoint = Baseline (pre-intervention), Timepoints 2 until 6 = during intervention, Timepoint 7 = immediately after intervention, Timepoint 8 = 1 week after intervention.
A Posner paradigm is used to measure the primary outcome. Three squares with a size of 1.5°, 2 located at 7° to the left and right of the fixation cross and 1 in the center of the screen are presented. A cue is presented for 100ms. Subsequently, a target is presented 150ms or 1100ms after cue onset for 100ms, in the left or right square (size of 1.4°). Cues and targets appear on the left or right side of the screen with equal probability. The cue can be valid (i.e., same side as target) in 40% of trials, invalid (i.e., opposite to target side) in 40% of trials or not followed by a target in 20% of trials. Patients have to respond as quickly as possible when they see the target. There will be 400 experimental trials that are presented in 4 blocks of 100 trials. The order of the trials is randomized. Our primary outcome measure is the change in the response times on invalid-cued targets for the shortest SOA on the Posner task.
次要结局
- Change in the Catherina Bergego Scale (CBS) score(This outcome variable is measured at 4 time points. Timepoint 1 = Baseline (before intervention), Timepoint 2 = during intervention, Timepoint 3 = Immediately after intervention, Timepoint 4 = 1 week after intervention.)
- Change in McIntosh Line Bisection endpoint weighting bias(This outcome variable is measured at 4 time points. Timepoint 1 = Baseline (before intervention), Timepoint 2 = during intervention, Timepoint 3 = Immediately after intervention, Timepoint 4 = 1 week after intervention.)