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Published on: June 12, 2019
The test of infant motor performance: reliability in spinal muscular atrophy type I
Richard S Finkel1, Linda S Hynan, Allan M Glanzman
1Department of Neurology, Division of Neurology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, USA. finkel@email.chop
Insights
The Test of Infant Motor Performance (TIMP) is reliable for assessing infants with spinal muscular atrophy type I (SMA-I). This tool provides consistent results for tracking motor development in these children.
Area of Science:
- Pediatric Neurology
- Motor Development Assessment
- Neuromuscular Disorders
Background:
- Spinal muscular atrophy type I (SMA-I) is a severe genetic neuromuscular disorder affecting motor neuron function.
- Accurate and reliable assessment tools are crucial for monitoring disease progression and treatment efficacy in infants with SMA-I.
- The Test of Infant Motor Performance (TIMP) is designed to evaluate early motor skills in infants.
Purpose of the Study:
- To evaluate the reliability of the Test of Infant Motor Performance (TIMP) in infants diagnosed with spinal muscular atrophy type I (SMA-I).
- To determine if TIMP scores are consistent when administered by different physical therapists (interrater reliability) and when administered to the same infant over time (test-retest reliability).
Main Methods:
- Interrater reliability was assessed using 17 physical therapists evaluating 6 infants with hypotonia and weakness.
- Test-retest reliability involved 8 trained physical therapists administering the TIMP twice, approximately one month apart, to 11 infants with genetically confirmed SMA-I.
- Infants in the test-retest study included 5 boys and 6 girls aged 37-501 days, with 3 on pulmonary support.
Main Results:
- The interrater reliability training session yielded a weighted Kappa of 0.61, indicating good agreement among evaluators.
- The test-retest reliability study showed a high intraclass correlation coefficient (ICC) of 0.85 for the TIMP Total Score, demonstrating excellent consistency over time.
- No significant differences were found between the two test sessions for the infants with SMA-I.
Conclusions:
- The Test of Infant Motor Performance (TIMP) demonstrates reliable and consistent scoring when used with infants diagnosed with spinal muscular atrophy type I (SMA-I).
- TIMP is a dependable tool for assessing motor performance in this vulnerable pediatric population, supporting clinical decision-making and research.
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.
