Validation and refinement of prediction models to estimate exercise capacity in cancer survivors

Exercise and physical activity is important for rehabilitation among cancer survivors. In a recent individual patient data meta analysis, we concluded that exercise, and particularly supervised exercise, effectively improves quality of life and physical fitness in patients with cancer with different demographic and clinical characteristics during and following treatment. Although effect sizes were small, there is consistent empirical evidence to support implementation of exercise as part of cancer care.

In order to test the effects of exercise interventions, to tailor exercise interventions, and to monitor progress among cancer survivors and patients with cancer, valid and reliable measures to assess exercise capacity are needed. In a paper just published in Archives of Physical Medicine and Rehabilitation -with Dr. Martijn Stuiver as first author- we tested the validity and clinical usefulness of the Steep Ramp Test for estimating exercise tolerance in cancer survivors, by external validation and extension of previously published prediction models for maximal or peak oxygen consumption (VO2peak; which is regarded as the gold standard measurement of cardiorespiratory fitness) and peak power output (Wpeak). Based on this study we concluded that predictions of VO2peak and Wpeak based on the steep ramp test are adequate at the group level, but insufficiently accurate in individual patients. The multivariable prediction model for Wpeak can be used cautiously to aid endurance exercise prescription.