Validation of Actigraphy in Middle Childhood.
Few studies have examined the validity of actigraphy in school-aged children. The objective of this study was to examine the validity of a commonly used actigraph compared to polysomnography (PSG) in a sample of children age 5 to 12 y born prematurely, sleeping in their natural home environment.



148 children born preterm (85 boys and 63 girls), ages 5-12 y (mean = 9.3 y, standard deviation = 2.0) wore the Philips Respironics Actiwatch-2 for 1 night concurrently with comprehensive, ambulatory PSG in the child's home. Sleep outcome variables were sleep onset latency, total sleep time (TST), and sleep efficiency. Epoch-by-epoch comparisons were used to determine sensitivity, specificity, and accuracy. Secondary analyses examined differences between children with no sleep issues, obstructive sleep apnea syndrome, and periodic limb movements in sleep (PLMS).



Actigraphy significantly underestimated TST (30 min) and sleep efficiency (5%). Actigraphy underestimated or overestimated sleep onset latency by at least 10 min for a third of the children. Sensitivity and accuracy were good at 0.88 and 0.84, respectively, whereas specificity was lower at 0.46. Differences between actigraphy and PSG for TST and sleep efficiency were greatest for children with PLMS.



This study adds to the small existing literature demonstrating the validity of actigraphy in middle childhood. Although actigraphy shows good sensitivity (ability to detect sleep), specificity (ability to detect wake) is poor in this age group. Further, the results highlight the importance of considering whether a child has PLMS when interpreting actigraphic data, as well as the difficulties in accurately capturing sleep onset latency with actigraphy.
Department of Pediatrics, National Jewish Health, Denver, CO.
Lisa J
LJ
Meltzer
Respiratory Medicine Service, Department of Paediatric Medicine, KK Women's and Children's Hospital, Singapore.
Petrina
P
Wong
The Ritchie Centre, Monash Institute of Medical Research-Prince Henry's Institute and Department of Paediatrics, Monash University, Clayton, VIC, Australia.
Sarah N
SN
Biggs
Sleep Center, Children's Hospital of Philadelphia, Philadelphia, PA.
Joel
J
Traylor
Clinical and Translational Research Center, Children's Hospital of Philadelphia, Philadelphia, PA.
Ji Young
JY
Kim
Department of Pediatrics, The University of Chicago, Chicago, IL.
Rakesh
R
Bhattacharjee
Respiratory Medicine, The Hospital for Sick Children, Toronto, ON, Canada.
Indra
I
Narang
Sleep Center, Children's Hospital of Philadelphia, University of Pennsylvania, Philadelphia, PA.
Carole L
CL
Marcus
D056044:Actigraphy / Q000592:standards*; D002648:Child; D002675:Child, Preschool; D004777:Environment; D005260:Female; D006801:Humans; D008297:Male; D020189:Nocturnal Myoclonus Syndrome / Q000503:physiopathology; D017286:Polysomnography; D047928:Premature Birth; D012680:Sensitivity and Specificity; D012890:Sleep / Q000502:physiology*; D020181:Sleep Apnea, Obstructive / Q000503:physiopathology; D013997:Time Factors; D014851:Wakefulness / Q000502:physiology
accelerometer; actigraphy; children; polysomnography; sensitivity; specificity; validation