START-Play (Sitting Together and Reaching to Play)

START-Play is a physical therapy intervention for infants aged 7-16 months with neuromotor disorders who are beginning to sit. The intervention embeds cognitive constructs (means-end relations, object permanence, object affordances, joint attention) within motor activities focused on sitting and reaching. Physical therapists deliver the intervention twice weekly for 12 weeks (up to 24 sessions, averaging 51.5 minutes each) through home visits with the infant and at least one parent or caregiver. The intervention advances motor and cognitive skills together at the "just-right" level through parent-therapist brainstorming, allows movement flexibility without rigid adherence to normal patterns, and is provided within a social, engaging context guided by degrees of joint attention. Physical therapists received training including review of theoretical evidence, in-person hands-on training with infants, ongoing critique and feedback on treatment sessions, and refresher training until reaching preset adherence levels.