Reliability and validity of the Omron HJ-720 ITC pedometer when worn at four different locations on the body

Abstract

Purpose: To determine the reliability and validity of the Omron HJ-720 ITC pedometer when worn at four different locations on the body. Methods: Subjects wore pedometers at the hip, chest, back, and pocket. Subjects’ stature, body mass, and stride length were entered in to each pedometer prior to walking one mile on a track while wearing a portable metabolic analyzer. Results: Intraclass correlation coefficients (ICCs) revealed that the pedometer produced high and statistically significant inter-device reliability for steps (ICC = 0.95), distance (ICC = 0.93), and kcal expenditure (ICC = 0.87), regardless of placement on the body. Measures of percent agreement and one-way ANOVAs revealed that the pedometer was valid for measures of steps and distance, but there was a statistical difference between actual and pedometer-estimated kcal expenditure (p < 0.05). Conclusions: Although the Omron pedometer produced reliable results regardless of placement on the body, it did not produce valid estimates of kcal expenditure.

Keywords:

• pedometer
• steps
• kilocalorie expenditure
• reliability
• validity
• physical activity

Public Interest Statement

When purchasing a physical activity monitoring device, such as a pedometer, consumers are often curious to know if the manufacturer’s claims are true and accurate. The purpose of this research was to investigate the claim that the Omron HJ-720 ITC pedometer is accurate when worn at various locations on the body.

Competing Interests

The authors declare no competing interest.

Additional information

Notes on contributors

Kimberly A. Smith

Dr Kimberly A. Smith is an Associate Professor of Exercise Science in the Department of Exercise and Rehabilitative Sciences at Slippery Rock University. Dr Smith earned a BS in Exercise Science from Slippery Rock University and MS and PhD degrees in Exercise Physiology from the University of Pittsburgh. She has been teaching at Slippery Rock University for 11 years, during which she has conducted several faculty-student collaborative research projects and coordinates a campus wide pedometer-based walking program. Dr Smith’s research interests include investigating physical activity interventions and physical activity monitoring devices. Dr Smith’s teaching philosophy focuses on inspiring students by bringing enthusiasm and eagerness into the classroom, all while facilitating a solid and challenging education based upon theory, science, and practical application.