Children's amputee mobility predictor-Assessing the functional capability of children with leg length discrepancy.

Objective: The study purpose was twofold: (1) to develop the Children's Amputee Mobility Predictor and establish its content and social validity and (2) to determine its intra and inter-rater reliability.

Design: A reliability and validity study.

Setting: Pediatric rehabilitation hospital.

Participants: Content validity study: 10 clinical experts; Social validity study: 24 stakeholders (i.e., children's parents); Reliability study: 3 physical therapists.

Intervention: Not applicable.

Main measure: The functional capability of 30 children with leg length discrepancy was evaluated using the Children's Amputee Mobility Predictor. The Intraclass Correlation Coefficient, two-way mixed model, and absolute agreement for a single measure were used to establish intra and inter-rater reliability.

Results: Experts reached a consensus on the relevancy and clarity of all 26 tasks included in the Children's Amputee Mobility Predictor. The intra- and inter-rater reliability were excellent, Intraclass Correlation Coefficient (ICC)_2,1= .95, with 95% CI ranging from 0.88-0.98; and ICC_3,1 = 0.96 with 95% CI ranging from 0.93-0.98, respectively. Parent feedback indicated the relevancy of tasks for children with leg length discrepancies.

Conclusions: The Children's Amputee Mobility Predictor is a comprehensive outcome measure that requires minimal equipment or space. It appears stable over time when used by the same physical therapist and results suggest that it may be used by multiple physical therapists. The Children's Amputee Mobility Predictor appears to measure important and relevant aspects of functional capability and be a meaningful and relevant assessment tool, helping to guide the determination of medical necessity for specific prosthetic and physical therapy interventions.