The test of infant motor performance: reliability in spinal muscular atrophy type I.

OBJECTIVE

The aim of this article was to determine reliability of the Test of Infant Motor Performance (TIMP) in infants with spinal muscular atrophy, type I (SMA-I).

METHODS

Interrater reliability training was undertaken by 17 physical therapist evaluators using 6 infants with hypotonia and weakness (5 videotaped, 1 live). Eight trained evaluators then conducted a test-retest reliability study at their own center, performing 2 tests approximately 1 month apart on each of 11 infants with genetically confirmed SMA-I (5 boys, 6 girls; age range 37-501 days; 3 on pulmonary support).

RESULTS

The interrater reliability training session had an overall weighted Kappa of 0.61 (95% confidence interval 0.59-0.63). For the test-retest reliability study, the intraclass correlation coefficient for the TIMP Total Score was 0.85 (95% confidence interval: 0.54-0.96). The test scores were not significantly different between the 2 sessions (Bradley-Blackwood test was nonsignificant).

CONCLUSIONS

TIMP scores can be reliably obtained in infants with SMA-I.