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

Pediatr Phys Ther. Fall 2008;20(3):242-6. doi: 10.1097/PEP.0b013e318181ae96.


Purpose: 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).

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

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Child Development*
  • Female
  • Humans
  • Infant
  • Male
  • Motor Skills / physiology*
  • Observer Variation
  • Physical Therapy Specialty / instrumentation*
  • Physical Therapy Specialty / standards*
  • Reproducibility of Results
  • Spinal Muscular Atrophies of Childhood / diagnosis
  • Spinal Muscular Atrophies of Childhood / physiopathology*
  • Video Recording