Optimal timing of the General Movement Assessment for early detection of cerebral palsy
Colleen Peyton, David Aaby, Vanessa M. Barbosa, Lynn Boswell, Olena Chorna, Sabrina Del Secco, Ginerva Costagli, Cathryn Crowle, Andrea Guzzetta, Christine Janssen, Amanda Kwong, Joy Olsen, Cathryn Morgan, Lucia Rocchitelli, Theresa Sukal‐Moulton, Monica Toohey, Alicia SpittleAbstract
Aim
To identify trajectories of normal fidgety movements between 10 weeks and 20 weeks corrected age and determine the optimal timing of the General Movement Assessment (GMA) to improve early cerebral palsy detection.
Method
In this prospective multicenter cohort study, parents submitted up to six serial home videos (median five per infant) between 10 weeks and 20 weeks corrected age using the Baby Moves smartphone application. GMA was performed by certified raters masked to age and clinical history. Group‐based trajectory modelling identified patterns of normal fidgety movement expression over time.
Results
A total of 438 infants (233 males, 205 females) contributed 2075 videos. Four trajectories were identified: consistent fidgety (22%), later fade (63%), later onset (10%), and low prevalence (5%). The greatest overlap in normal fidgety movements occurred at 14 to 15 +6 weeks corrected age. Approximately 10% of infants (later onset) demonstrated emergence of normal fidgety movements after the currently recommended initial assessment window. The low prevalence trajectory was associated with lower gestational age and greater neonatal morbidity.
Interpretation
Timing influences fidgety movement classification and may affect early cerebral palsy detection. Assessment at 14 to 15 +6 weeks corrected age may reduce early misclassification.