Strycker LA, Duncan SC, Chaumeton NR, Duncan TE, Toobert DJ. Reliability of pedometer data in samples of youth and older women. Int J Behav Nutr Phys Act 2007 Feb 17;4:4.


BACKGROUND: Pedometers offer researchers a convenient and inexpensive tool for objective measurement of physical activity. However, many unanswered questions remain about expected values for steps/day for different populations, sources of variation in the data, and reliability of pedometer measurements. METHODS: This study documented and compared mean steps/day, demographic predictors of steps/day, and pedometer reliability in two longitudinal investigations, one involving a population-based youth sample (N = 367) and the other targeting postmenopausal women with type 2 diabetes (N = 270). Individuals were asked to wear pedometers (Yamax model SW-701) at the waist for 7 days and record steps/per day. They were also asked to record daily physical activities, duration, and perceived intensity (1 = low/light, 2 = medium/moderate, 3 = high/hard) for the same 7 days. In addition, survey data regarding usual physical activity was collected. Analyses of variance (ANOVA) were conducted to determine whether there were significant differences in pedometer results according to sex, age, and body mass index. Repeated measures ANOVAs were used to examine potential differences in results among differing numbers of days. RESULTS: Mean steps/day were 10,365 steps in the youth sample and 4,352 steps in the sample of older women. Girls took significantly fewer steps than boys, older women took fewer steps than younger women, and both youth and women with greater body mass took fewer steps than those with lower body mass. Reliability coefficients of .80 or greater were obtained with 5 or more days of data collection in the youth sample and 2 or more days in the sample of older women. Youth and older women were more active on weekdays than on weekends. Low but significant associations were found between step counts and self-report measures of physical activity in both samples. CONCLUSION: Mean steps/day and reliability estimates in the two samples were generally consistent with previously published studies of pedometer use. Based on these two studies, unsealed pedometers were found to offer an easy-to-use and cost-effective objective measure of physical activity in both youth and older adult populations.

Full Text

The full text is available at https://dx.doi.org/10.1186/1479-5868-4-4

At A Glance

Individual Physical Activity Behavior Variables

Step/Activity Counts


Individual Physical Activity Behavior

Measure Type

Electronic monitor (e.g., accelerometer, pedometer, heart rate)

Measure Availability

Cost associated. Access at Yamax Corporation, Japan

Number of Items

Not applicable

Study location


Pacific Northwest, USA


Not applicable

Information about Development of Measure

Nothing to add

Study Design

Study Participants


6 - 11 Years

12 - 18 Years





Not reported

Predominantly Low-income/Low-SES

Not reported

Sample Size


Study Design

Design Type


Health Outcomes Assessed


Obesity Measures

Not applicable

BMI Measured or Self-reported

Not applicable


Not reported

Data Reported on Race/Ethnicity

Not applicable

Data Reported on SES

Not applicable

SES-related Variables

Not applicable

How To Use


Who Administered



How Administered


Time Required

7 days

Training Required

Yes, time not reported

Instructions on Use

Access at Yamax Corporation, Japan

Data Analysis

Data Collection/Analysis Costs

Not available

Data Collection/Protocol

Not available

Instructions on Data Analysis

Not reported

Validity (0)

There are no validity tests reported for this measure.

Reliability (4)

Type of reliability Construct/subscale assessed Test/statistic used Result
Test-retest Reliability of pedometer measurements - 4 days Cronbach's alpha Youth: 0.78; Older women: 0.85
Test-retest Reliability of pedometer measurements - 3 days Cronbach's alpha Youth: 0.78; older women: 0.86
Test-retest Reliability of pedometer measurements - 2 days Cronbach's alpha Youth: 0.73; Older women: 0.84
Test-retest Reliability of pedometer measurements - 5 days Cronbach's alpha Youth: 0.82; Older women: 0.87