Vos-Vromans, Desirée C W M, Huijnen, Ivan P J, Köke, Albère J A et al. · Journal of psychosomatic research · 2013 · DOI
This study looked at whether ME/CFS patients who are more physically active differ from those who are less active in how much they can actually do and how they feel about their abilities. Researchers gave 60 patients activity monitors to track their real-world movement and asked them questions about their functioning. They found that more active patients could stay upright longer and had more consistent activity levels day-to-day, but the two groups were surprisingly similar in most other ways.
This research addresses a fundamental clinical assumption in ME/CFS treatment: that patients can be meaningfully divided into 'active' and 'passive' subtypes. If these categories don't reflect actual differences in functioning, it could inform how therapists tailor interventions and help clarify whether current classification methods are evidence-based or need revision.
This study does not prove that activity-based subgroups do not exist in ME/CFS—only that therapist judgment may not reliably identify them using current criteria. It also does not demonstrate causation between activity level and outcomes, nor does it validate or refute cognitive behavioral therapy as an appropriate treatment. The cross-sectional baseline design cannot show whether these categorizations predict response to treatment.
About the PEM badge: “PEM required” means post-exertional malaise was an explicit required diagnostic criterion for participant inclusion in this study — not that PEM was studied, observed, or discussed. Studies using criteria that do not require PEM (e.g. Fukuda, Oxford) are tagged “PEM not required”. How the atlas works →
The first block is for the primary paper and is the citation you should use in research work. The atlas-snapshot line only applies if you are specifically referring to this atlas’s reading of the paper on the date shown.
Primary citation
Vos-Vromans, Desirée C W M, Huijnen, Ivan P J, Köke, Albère J A, Seelen, Henk A M, Knottnerus, J André, & Smeets, Rob J E M (2013). Differences in physical functioning between relatively active and passive patients with Chronic Fatigue Syndrome.. Journal of psychosomatic research. https://doi.org/10.1016/j.jpsychores.2013.05.001
BibTeX
@article{mecfsatlas-vos-vromans-2013-differences-physical,
author = {Vos-Vromans, Desirée C W M and Huijnen, Ivan P J and Köke, Albère J A and Seelen, Henk A M and Knottnerus, J André and Smeets, Rob J E M},
title = {Differences in physical functioning between relatively active and passive patients with Chronic Fatigue Syndrome.},
journal = {Journal of psychosomatic research},
year = {2013},
doi = {10.1016/j.jpsychores.2013.05.001},
note = {PubMed: 23972414},
url = {https://www.mecfsatlas.com/evidence/vos-vromans-2013-differences-physical},
}Atlas snapshot reference
ME/CFS Atlas. Generator v1 / Scanner v1.4 / policy v0.1. Accessed 2026-05-29. https://www.mecfsatlas.com/evidence/vos-vromans-2013-differences-physical
Contribute
Private, reviewed by a human. Not a public comment thread.