*2.1. Design*

This is a feasibility trial of a mixed-methods case series, prospectively registered, with 3-month intervention and 1-month follow-up. The follow-up will aim to assess preliminary learning retention and implications of modified ride-on car training sessions [16]. This prospective study will provide important information about the feasibility, assistive effectiveness, and rehabilitative effectiveness of the first intervention focusing on powered mobility for children with CZS in Brazil. The procedures and timeline of the study are included in Figure 1 and Table 1.

**Figure 1.** Go Zika Go timeline and procedure intervention for children with congenital Zika syndrome (CZS) between 1.5–5 years age.



PEDI-CAT: Pediatric Evaluation of Disability Inventory–Computer Adaptive-test; YC-PEM: Young Children's Participation and Environment Measure; GAS: Goal Attainment Scaling; PFQ: Parents Feasibility Questionnaire; ALP: Assessment of Learning Powered Mobility.

#### *2.2. Participants*

Inclusion criteria: (a) Diagnosis of CZS, (b) GMFCS [21], level IV or V, (c) aged between 1.5 and 5 years, (d) no previous experience with powered mobility.

Exclusion criteria include the presence of uncontrolled seizures and musculoskeletal deformities that prevent adaptation of the seating support in the device.

#### *2.3. Sample Size Estimation*

In this feasibility study, we will recruit 10 children with CZS. This small sample will provide data on the feasibility of the protocol, thus helping determine the sample size for a larger randomized trial using powered mobility in children with CZS. Given the lack of previous studies measuring the outcomes of interest for this study, the sample size was estimated according to recommendations of the minimum sample for pilot studies [22].
