Validation of Omron Pedometer and Yamax DigiWalker against criterion hand tally

Aim. This study was designed to assess the criterion-related validity of the Omron HJ-105 and the DigiWalker 651 pedometers against the criterion hand tally counter and the StepWatch accelerometer. Methods. Forty-three female women aged 20 to 60 years wore Omron HJ-105 and the DigiWalker 651 pedometers on the interior hip, exterior hip and ankle along with the StepWatch accelerometer on the ankle while walking on a treadmill at 1 mph twice and then at 3 mph for two trials. Results. At 1 mph, the StepWatch had the lowest percent error (7%). At 3 mph, the Omron worn at the ankle had the highest percent error (34%) and the DigiWalker worn at the exterior hip had the lowest percent error (5%). The greatest variability was seen with the Omron at both 1 mph (interior hip, mean difference ± SEM, -64.6 ± 18.6 counts) and 3 mph trials (ankle, 108.1 ± 12.6 counts). Conclusion. At the slower speed, the DigiWalker at the ankle is the most cost-effective and accurate device for use. To maximize accuracy in step counting, knowledge of usual walking speed should influence the choice of pedometer and where it should be worn.