Related Experiment Video
Updated: Jul 18, 2026

Quantitative Autonomic Testing
Published on: July 19, 2011
Test-retest reliability of heart rate variability and respiration rate at rest and during light physical activity in
Alida M Guijt1, Judith K Sluiter, Monique H W Frings-Dresen
1Coronel Institute of Occupational Health, Academic Medical Center, Universiteit van Amsterdam, Amsterdam, The Netherlands.
Background:
A variable that remains stable over repeated measurements (in stable conditions) is ideal for tracking modifications of the clinical state. The aim of the present study is to examine test-retest reliability of time-domain heart rate variability and respiration rate measurements using a portable device on normal subjects during rest and light physical activity.
Methods:
Twenty-six normal subjects [18 females and 8 males aged 28 +/- 6 years and 34 +/- 12 years (mean +/- SD), respectively] underwent two measurements for time-domain heart rate variability (SDNN and RMSSD) and respiration rate, with 7 days in between. Measurements took place under three conditions: lying down in a laboratory, cycling in a laboratory and sleeping in an ambulatory surrounding. Reliability was assessed statistically by calculating intra-class correlation coefficients (ICC).
Results:
Reliability was found to be good to excellent for both time-domain heart rate variability (SDNN: ICC values between 0.74 and 0.85, RMSSD: ICC values between 0.75 and 0.98) and for respiration rate (ICC values between 0.77 and 0.96).
Conclusions:
Both time-domain heart rate variability and respiration rate can be reliably assessed. However, we advise reliability research in a clinical setting before using the device for tracking modifications in a clinical state.
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