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Population-based age standards for interpreting results on the test of motor infant performance
Suzann K Campbell1, Paul Levy, Laura Zawacki
1Department of Physical Therapy, College of Applied Health Sciences, University of Illinois at Chicago, Chicago, Illinois, USA.
Insights
This study established age standards for the Test of Infant Motor Performance (TIMP), finding that high-risk and Latino infants scored lower, indicating potential developmental delays. These findings aid in identifying infants needing early intervention for motor development.
Area of Science:
- Pediatric developmental assessment
- Infant motor development research
- Clinical assessment tools
Background:
- The Test of Infant Motor Performance (TIMP) is a crucial tool for assessing infant motor skills.
- Establishing normative data is essential for accurate interpretation of TIMP scores.
- Understanding group differences can refine developmental outcome predictions.
Purpose of the Study:
- To establish age-specific performance standards for the Test of Infant Motor Performance (TIMP).
- To investigate potential differences in TIMP scores based on sex, medical risk, and race/ethnicity.
- To provide a benchmark for identifying infants with delayed motor development.
Main Methods:
- Recruited 990 infants across the US, reflecting diverse race/ethnicity distributions.
- Tested infants in two-week age ranges from 34-35 weeks' postconceptional age to 16-17 weeks post-term.
- Utilized multiple regression to analyze the impact of sex, medical risk, and race/ethnicity on TIMP scores.
Main Results:
- Developed age-based performance expectations for TIMP scores, ranging from 49 to 120.
- Identified significantly lower scores in high-risk infants (beta = -0.133, P < 0.0001).
- Observed lower scores in Latino infants compared to other ethnicities (beta = -0.052, p < 0.006); no sex differences found.
Conclusions:
- The established TIMP age standards enable the identification of infants with delayed motor development.
- Medical risk and Latino ethnicity are associated with lower motor performance scores.
- These findings support the clinical utility of TIMP in early identification and intervention.
Purpose:
The goals of this study were establishment of age standards for the Test of Infant Motor Performance (TIMP) and evaluation of possible group differences based on sex, medical risk for poor developmental outcome, and race/ethnicity.
Subjects:
Subjects were 990 infants with a range of risk for poor outcome from 11 geographic locations across the United States that were recruited to reflect the distribution of race/ethnicity in the US population of low birth weight infants.
Methods:
Between 67 and 97 infants were tested in each two-week age range from 34-35 weeks' postconceptional age through 16-17 weeks after term. Boys made up 52% of the subjects. Fifty-eight percent of the sample was white, 25% black, and the remainder were of other ethnicities. Scores for all infants in each age group were averaged to form age expectations for each two-week period. Multiple regression was used to explore the effect on TIMP scores of sex, risk, and race/ethnicity.
Results:
Means ranged from 49 (standard deviation = 15) at 34-35 weeks' postconceptional age through 120 (standard deviation = 16) at 16-17 weeks after term. High-risk infants scored significantly lower than other infants (beta = -0.133, P < 0.0001). Latino infants scored lower than infants of all other ethnicities (beta = -0.052, p < 0.006). Performance did not differ by sex. CONCLUSIONS/CLINICAL IMPLICATIONS: These standards for performance on the TIMP can be used to identify infants with delayed motor development.
