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How Many Days are Necessary to Represent Typical Daily Leg Movement Behavior for Infants at Risk of Developmental
Weiyang Deng1, Ryota Nishiyori2, Douglas L Vanderbilt3
1Division of Biokinesiology and Physical Therapy, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033, USA.
Insights
Two days of wearable sensor data effectively capture typical movement in at-risk infants, minimizing participant burden. Daily leg movement patterns showed no significant difference between weekdays and weekend days.
Area of Science:
- Developmental pediatrics
- Wearable sensor technology
- Infant movement analysis
Background:
- Movement characteristics differentiate infants at risk for developmental disabilities from those typically developing.
- Optimal data collection duration for at-risk infants using wearable sensors remains unclear.
- Balancing participant burden and data quantity is crucial for efficient data collection.
Purpose of the Study:
- Determine the number of days needed to represent typical movement behavior in at-risk infants.
- Investigate differences in movement behavior between weekend days and weekdays.
Main Methods:
- Collected leg movement data from 11 infants using Opal wearable sensors for at least 5 days.
- Compared 1-4 days of data to a 5-day standard using Bland-Altman plots and Spearman correlation.
- Analyzed differences in movement data between weekend days and weekdays for 8 infants.
Main Results:
- Spearman correlation coefficients above 0.7 and <10% absolute differences indicate 2 days of data represent the standard.
- Bland-Altman plots showed >90% of data points within limits of agreement for 2-day averages.
- Minimal differences (<15.2%) observed in leg movement rate, duration, and acceleration between weekend and weekdays.
Conclusions:
- Two days of data collection is optimal for representing typical leg movement behavior in at-risk infants, balancing data accuracy and participant burden.
- No distinct differences in leg movement behavior were found between weekend days and weekdays.
- Findings support efficient data collection strategies for evaluating infant movement using wearable sensors.
Background:
Movement characteristics can differentiate between infants at risk and infants with typical development. However, it is unknown how many days are needed to accurately represent typical daily behavior for infants at risk of developmental disabilities when using wearable sensors. To consider the balance between participant burden and the amount of data collected and optimizing the efficiency of data collection, our study determined (1) how many days were necessary to represent typical movement behavior for infants at risk of developmental disabilities and (2) whether movement behavior was different on weekend days and weekdays.
Methods:
We used Opal wearable sensors to collect at least 5 days of 11 infants' leg movement data. The standard (average of 5 days) was compared with four methods (average of the first 1/2/3/4 days) using the Bland-Altman plots and the Spearman correlation coefficient. We also compared the data from the average of 2 weekend days to the average of the first 2 weekdays for 8 infants.
Results:
The Spearman correlation coefficient comparing the average of the first 2 days of data and the standards were all above 0.7. The absolute differences between them were all below 10% of the standards. The Bland-Altman plots showed more than 90% of the data points comparing the average of 2 days and the standards fell into the limit of agreement for each variable. The absolute difference between weekend days and weekdays for the leg movement rate, duration, average acceleration, and peak acceleration was 15.2%, 1.7%, 6.8% and 6.3% of the corresponding standard, respectively.
Conclusion:
Our results suggest 2 days is the optimal amount of data to represent typical daily leg movement behavior of infants at risk of developmental disabilities while minimizing participant burden. Further, leg movement behavior did not differ distinctly across weekend days and weekdays. These results provide supportive evidence for an efficient amount of data collections when using wearable sensors to evaluate movement behavior in infants at risk of developmental disabilities.
