Validity of an Accelerometer Used to Measure Step Count in Children With Idiopathic Toe WalkingChristensen, Catie PT, DPT; Haddad, Amanda PT, DPT; Maus, Elizabeth PT, DPT, PCSPediatric Physical Therapy: April 2017 - Volume 29 - Issue 2 - p 153–157 doi: 10.1097/PEP.0000000000000364 Research Reports Abstract In Brief Author Information Purpose: To assess the validity of accelerometer use in children with idiopathic toe walking (ITW). Methods: Seventy-five children, 2 to 13 years old, with ITW were videotaped ambulating 50 ft wearing a NL-1000 accelerometer. Because of concerns for accelerometer accuracy in young children, 2 groups were created: 5 years or younger (n = 45) and 6 years or older (n = 30). Step counts recorded via accelerometer and video were compared and correlated. Results: There was a significant difference in accelerometer and video step counts for 2- to 5-year-olds (W = 72.00, P < .001). No significant difference was found for 6- to 13-year-olds (W = 65.00, P = .24). Spearman ρ values were 0.78 and 0.92 for the 5 years or younger and 6 years or older groups, respectively. Conclusion: Accelerometers accurately count steps in 6- to 13-year-olds with ITW but are inaccurate in 2- to 5-year-olds. This paper assesses whether accelerometers accurately measure step count in children with idiopathic toe walking aged between 2-13 years compared to videotaped observations. The Division of Clinical Therapies, Nationwide Children's Hospital, Columbus, Ohio. Correspondence: Catie Christensen, PT, DPT, Nationwide Children's Hospital, 433 North Cleveland Ave, Westerville, OH 43082 (Catie.Christensen@nationwidechildrens.org). The authors declare no conflicts of interest. Copyright © 2017 Wolters Kluwer Health, Inc. and Section on Pediatrics of the American Physical Therapy Association. All rights reserved.