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Movement Assessment of Children (MAC): validity, reliability, stability and sensitivity to change in typically
L S Chandler1,2, L Terhorst1, J C Rogers1
1Department of Occupational Therapy, University of Pittsburgh, Pittsburgh, PA, USA.
Insights
The Movement Assessment of Children (MAC) is a valid and reliable tool for assessing functional motor development in infants and toddlers. This family-centered assessment effectively monitors progress and identifies potential developmental delays.
Area of Science:
- Pediatric physical therapy
- Child development research
- Motor control and learning
Background:
- Early identification of motor delays is crucial for timely intervention and improved developmental outcomes in infants and toddlers.
- The Movement Assessment of Children (MAC) is designed as a family-centered tool to enhance infant responsiveness during assessment.
- Assessing functional motor development aids in monitoring at-risk populations and guiding therapeutic strategies.
Purpose of the Study:
- To establish the validity, reliability, stability, and sensitivity to change of the Movement Assessment of Children (MAC).
- To validate the MAC for use in typically developing infants and toddlers aged 2 months to 2 years.
- To provide age-related parameters for the MAC assessment in early childhood.
Main Methods:
- Utilized data from 276 children and 405 assessments to establish age-related parameters for the MAC.
- Examined construct validity by correlating MAC scores with participant age.
- Assessed inter-rater reliability, test-retest reliability, stability, and sensitivity to change using subsamples.
Main Results:
- Demonstrated strong construct validity for functional motor development.
- Achieved high inter-rater reliability (ICCs 0.83–0.99) for core MAC items and total scores.
- Confirmed stability over 6 months and significant sensitivity to change in motor development.
Conclusions:
- The Movement Assessment of Children (MAC) is a well-constructed and effective tool for assessing infant and toddler functional motor development.
- The MAC is a family-centered and efficient instrument suitable for assessment and follow-up from 2 months to 2 years.
- The study confirms the MAC's utility in monitoring motor development and supporting early intervention efforts.
Aim:
The purpose of this study was to establish the validity, reliability, stability and sensitivity to change of the family-centred Movement Assessment of Children (MAC) in typically developing infants/toddlers from 2 months (1 month 16 days) to 2 years (24 months 15 days) of age.
Background:
Assessment of infant/toddler motor development is critical so that infants and toddlers who are at-risk for developmental delay or whose functional motor development is delayed can be monitored and receive therapy to improve their developmental outcomes. Infants/toddlers are thought to be more responsive during the MAC assessment because parents and siblings participate and elicit responses.
Methods:
Two hundred seventy six children and 405 assessments contributed to the establishment of age-related parameters for typically developing infants and toddlers on the MAC. The MAC assesses three core domains of functional movement (head control, upper extremities and hands, pelvis and lower extremities), and generates a core total score. Four explanatory domains serve to alert examiners to factors that may impact atypical development (general observations, special senses, primitive reflexes/reactions, muscle tone). Construct validity of functional motor development was examined using the relationship between incremental increases in scores and increases in participants' ages. Subsamples were used to establish inter-rater reliability, test-retest reliability, stability and sensitivity to change.
Results:
Construct validity was established and inter-rater reliability ICCs for the core items and core total ranged from 0.83 to 0.99. Percent agreement for the explanatory items ranged from 0.72 to 0.96. Stability within age grouping was consistent from baseline to 6 months post-baseline, and sensitivity to change from baseline to 6 months was significant for all core items and the total score.
Conclusion:
The MAC has proven to be a well-constructed assessment of infant and toddler functional motor development. It is a family-centred and efficient tool that can be used to assess and follow-up of infants and toddlers from 2 months to 2 years.
