Reproducibility of peak oxygen uptake and other cardiopulmonary exercise parameters: implications for clinical trials and clinical practice

Chest. 2010 Oct;138(4):950-5. doi: 10.1378/chest.09-2624. Epub 2010 Jun 3.


Background: Clinical trialists involved in projects aimed at assessing the impact of a device or therapy on exercise capacity must select an end point that can detect a therapy-derived change and do so in a manner that is both sensitive to the change and valid. Using baseline data from the Prospective Evaluation of Elastic Restraint to Lessen the Effects of Heart Failure (PEERLESS-HF) trial, we describe the coefficient of variation (CV) for peak oxygen uptake (Vo2) and other parameters measured during a cardiopulmonary exercise (CPX) test.

Methods: Prior to conducting CPX testing, a CPX core laboratory conducted training with testing staff at each site, and a standardized quality assurance protocol was completed. During screening, subjects performed two symptom-limited CPX tests (CPX-0 and CPX-1) within 14 days.

Results: The CVs for peak Vo2, ventilatory efficiency, and ventilatory-derived anaerobic threshold were 5.9%, 4.8%, and 6.8%, respectively. During CPX-0, the percentage of subjects with a respiratory exchange ratio (RER) < 1.05 who increased their peak Vo2 by ≥ 6% during CPX-1 was 47%, compared with 12% of subjects also with an RER < 1.05 who experienced a decrease in peak Vo2 ≥ 6%.

Conclusions: In a multisite clinical trial setting, we showed that the achieved test-retest reproducibility for peak Vo2 can be acceptable, as evidenced by a CV at 5.9%. Until more data are available to identify patients who may demonstrate greater test-retest variance and to avoid repeat testing in all subjects at baseline, clinical trialists might consider repeating tests when RER < 1.05.

Trial registration:; Identifier: NCT00382863.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial

MeSH terms

  • Chi-Square Distribution
  • Endpoint Determination
  • Exercise Test*
  • Female
  • Heart Failure / physiopathology*
  • Humans
  • Male
  • Middle Aged
  • Oxygen Consumption / physiology*
  • Prostheses and Implants
  • Quality of Life
  • Reproducibility of Results
  • Walking / physiology

Associated data