Use of pedometers and accelerometers in clinical populations: validity and reliability issues

Abstract

Background: Pedometers and accelerometers are often used in clinical research studies, and have the potential to provide valid and objective information on physical activity.

Objectives: The purposes of this review are to introduce clinicians to various activity monitors that are commercially available, and to discuss their strengths and limitations. Scientific articles over the past 20 years were reviewed, and the most common types of physical activity monitors were identified. Emphasis was placed on devices with established validity and reliability, which were acceptable to participants and did not interfere with their activities. Ease-of-use from the investigator's standpoint was also considered.

Major findings: A number of activity monitors were identified, including four pedometers (Yamax SW digiwalker, New Lifestyles NL-2000, Omron HJ-720 ITC, and StepWatch), three accelerometer-based activity monitors (ActiGraph, Actical, and RT3), and a multisensor device (Sensewear Armband). Validity and reliability of these devices is discussed.

Conclusions: Pedometers and accelerometers are useful for tracking ambulatory physical activity in clinical populations, and those that display steps and/or calories are useful in motivating patients to increase their activity levels.

Keywords:

• MOTION SENSOR
• WALKING
• AMBULATION
• PHYSICAL ACTIVITY
• ENERGY EXPENDITURE