The three purposes of this study are: 1) to compare the effects on looking behaviors, visual fixation and social interaction through the use of a head- mounted, eye-tracker in toddlers with motor disabilities after receiving different intensity levels of ROC-Stand training; 2) to compare short-term and long-term outcomes in terms of body function, activity and participation across the ICF framework, family perceptions and participation; and 3) to identify factors that predict individual differences in outcomes for toddlers with motor delays with the two dosing protocols. Based on the power analysis from the pilot study, the investigators will recruit 30 toddlers with motor delays and further randomly assign the participants to the 3 groups with the same total amount of 48-hour training, including 2 ROC-Stand groups and 1 conventional therapy group, i.e., an intensity level of 2-hour session of ROC-Stand training (ROC-Stand(2-hr)) (n=10), an intensity level of 1-hour session of ROC-Stand training (ROC-Stand(1-hr)) (n=10), and an intensity level of 1-hour session of conventional therapy (Control(1-hr)) (n=10). The training frequency for the 3 groups is 2 sessions/per week. The whole study duration will be 1 year. The head-mounted cameras worn by the participants will record the visual and interactive behaviors for 20 minutes/per week during intervention. Standardized assessments are provided for a total 4 times, including the time before training (T1), 3 months following initiation of training (T2), 6 months following initiation of training (T3), and the end of a year following initiation of training (T4). Assessments include body function, activity and participation across the ICF domains, family perception and participation. The findings of this study will provide guidelines for adjusting the dosage parameters of early powered mobility depending on each child's and family's needs.

To evaluate the varying dosages' impact, the pilot RCT studied two different intensity levels of the ROC-Stand training for toddlers with motor delays. Initial findings suggest that the 48-hour regimen (2 hours per session, 2 sessions weekly) and the 24-hour approach (1 hour per session, 2 sessions weekly) have beneficial effects on the mobility and social functionalities of the toddlers. While enhancements were observed across the board during the 12-week intervention and follow-up phases, it was the ROC-48 group that showcased the most significant number of participants achieving clinically meaningful changes. This data implies that a 48-hour dose of ROC-Stand training may be the optimal requirement for noted improvements. Furthermore, another pilot study involving two participants using a lightweight, head-mounted eye-tracker by Positive Science, LLC during the ROC training phase has highlighted a positive trend in visual behaviors. Post-training, there was a noticeable increase in participants' interactions with their surroundings, particularly during social encounters and navigation. On the flip side, the frequency with which they observed faces and bodies reduced. The integration of eye-tracking technology showcases its potential in gauging participants' behaviors during self-initiated movements and interactions with the environment and caregivers. It offers a promising avenue to discern the type of visual and social cues acquired during early powered mobility training, aiding in comprehending environmental factors' influence on the psychosocial functions in toddlers with motor delays.

This study seeks to address the quest for determining the minimal effective dosage and to bolster its clinical utility in Taiwan. The research intends to contrast the effectiveness of two intensity levels of the ROC-Stand training, namely 2-hour and 1-hour sessions, targeting children aged between 1-3 at the outset of the intervention. With a 1-year follow-up, the study will not only provide insights into the ROC-Stand training but will also introduce a control group receiving the conventional 1-hour weekly therapy. To ensure consistency, each group will be subjected to the same frequency and duration, totaling 48 hours of intervention. This design of three-group comparison will enable us to define precise dosing benchmarks, incorporating a 2-hour ROC-Stand session (ROC-Stand(2-hr)), a 1-hour ROC-Stand session (ROC-Stand(1-hr)), and a 1-hour conventional therapy session (Control(1-hr)). Pinpointing these intensity benchmarks is vital for guiding clinical decisions and influencing health policy. In addition, the study's incorporation of a novel head-mounted eye-tracker, specifically tailored for young movers, anticipates capturing the nuances and diversities of real-world mobility interactions.

Method: This study will use a randomized, multi-group pretest-posttest control group design. Each group will undergo an intervention with a consistent frequency and duration, specifically, 2 sessions per week culminating in a total of 48 hours of training. The study will utilize a 3-group comparison structure, focusing on two distinct intensity levels. Building on previous research and the aims of this study, the three groups will be distinguished by the intensity of their respective training sessions: The ROC-Stand(2-hr) group will participate in 2-hour sessions twice a week for a total of 12 weeks (3 months). In contrast, both the ROC-Stand(1-hr) and Control(1-hr) groups will attend 1-hour sessions twice weekly for a period of 24 weeks (6 months).

Participants: The study will involve 30 toddlers aged between 12 to 36 months, all exhibiting motor delays. These participants will be randomly allocated to one of three groups: ROC-Stand(2-hr) (10 toddlers), ROC-Stand(1-hr) (10 toddlers), or Control(1-hr) (10 toddlers). Given the emphasis on early powered mobility training, the sample size determination hinges on an effect size f of 0.3, derived from preliminary PEDI-C mobility function data. With a power set at 0.8, a two-sided type I error rate of 0.05, anticipated 20~25% attrition, and drawing from recruitment patterns in past studies, the resulting requisite total sample size is estimated at 30 toddlers.

Recruitment: The participants will be recruited from self-referrals, health care practitioners, or the hospitals in Taoyuan or New Taipei where toddlers with motor delays are receiving outpatient rehabilitation. Children of parents/guardians who provide informed consent will participate in the study.

Procedure: Participants will undergo pre-intervention evaluations encompassing standardized developmental assessments, home environment and parental perception questionnaires. These will be administered by a licensed, independent OT, who is not participating in the training. Assessments will be conducted at four intervals: prior to training (T1), 3 months post-initiation (T2), 6 months post-initiation (T3), and a year after starting (T4). All participants will commence their training at the university. During the intervention, a lightweight head-mounted eye-tracker will record participants' eye gaze, manual actions, and social interactions once a week. An activity log, previously used in other studies, will document training conditions and caregiver feedback weekly. In the follow-up stage, participants will only attend their usual therapy sessions outside the study. Details of these sessions, including type, frequency, and dosage, will be documented at all four testing intervals. Undergraduate students will code the eye-tracking data. To ensure reliability, inter-rater scores will be calculated between these coders before the formal coding process begins.

Intervention:Two licensed occupational therapists who involve providing the training programs will ask caregivers to identify goals and measure progress using goal attainment scaling (GAS) at T1, T2, T3 and T4 time points for the 3 groups. The ROC-related programs require one therapist working with the caregivers based on the coaching technique described in the family-centered service model. The ROC involves a standing posture. The training principles are similar to those applied in the previous studies of ROC training in various environments. The conventional therapy program is a child-centered, therapist-directed program which is implemented by another therapist. Participants will have a necessary break depending on their endurance during training. In addition, all participants in the 3 groups will wear an eye-tracking headgear (Positive Science, LLC) to record the looking, fixation and interactive behaviors for one session/per week during intervention. All participants in the 3 groups will continue their regular therapy from their own clinics throughout the 1-year duration of the study, including physical therapy, occupational therapy, speech therapy, and other therapy.

Follow-up: This period will involve a follow-up phase following the above treatment programs; during this time no training programs will be delivered to the participants except for their own regular therapy.

Instrument and Procedure: To obtain the data of locomotor experience, an objective measure of using a head-mounted, eye-tracker and qualitative measures of activity logs will be applied during the intervention (training) phase. Standardized assessments as the quantitative measures will be administered at T1, T2, T3 and T4 in a testing room of the university. An independent, licensed OT who is blinded to the group assignment and study hypotheses will complete the assessments.

Descriptive statistics (frequency, means, standard deviations) of each behavior will be calculated. Kolmogorov-Smirnov will be used to examine whether the data follows a normal distribution. To compare the baseline characteristics of the major 3 groups, one way ANOVA (for data with normal distribution) and Kruskal-Wallis analysis of variance (for data with non-normal distribution) will be conducted. Data will be analyzed based on an intention-to-treat analysis. For those data collected during the intervention phase, descriptive statistics (frequency, means, standard deviations) of looking behaviors, visual fixation and interactive behaviors will be calculated and repeated measures analysis of variance will be used to compare the effects on each exploratory behaviors among the 3 training groups during intervention. A repeated measures analysis of variance (group [3] × time [4]) will be employed to evaluate the treatment effects on the secondary outcomes within and among the 3 groups at T1, T2, T3 and T4, followed by a post-hoc analysis using Bonferroni test to determine between which groups the differences occur. To clarify the relationship between other relevant factors and psychosocial outcomes, the investigators will consider two co-variates in the analysis based on previous research: motor composite scores from the Bayley-III and caregiver-child dysfunctional interaction (obtained from parenting stress index). Last, the investigators will apply a coefficient test for analyzing the relationship among the social function, looking/manual actions and social interactions, and caregiver-child dysfunctional interaction during the intervention phase in each group. SPSS 21.0 (SPSS Inc. Chicago, Illinois, USA) will be used for statistical analysis. Significance level will be set at p < 0.05.

Inclusion Criteria:

1. age between 1-3 years old
2. motor delays that resulted in motor delays that prevented independent walking (> 1.5 standard deviation [SD] below the mean, assessed by the Chinese Child Development Inventory via a pediatric physician)
3. being able to stand independently for two seconds or tolerate standing with support for 10 minutes
4. being able to reach objects with either one or both hands
5. 69 to 103 cm height and 7 to 18 kg weight
6. parents agreeing to provide consent for their child's participation in the training program

Exclusion Criteria:

1. children with severe sensory impairments (including blindness or deafness)
2. exceeding the height or weight criteria
3. parents/guardians who are unable to make the time commitment for the program
4. children with severe emotional reactions which may result in harm