Tools

Vanderbilt Orthostatic Symptom Score (VOSS)

Nine symptoms rated 0–10 while upright: the standing symptom score from POTS trials

The Vanderbilt Orthostatic Symptom Score comes from the Vanderbilt Autonomic Dysfunction Center, where Satish Raj and colleagues used it in POTS drug studies from 2005 onwards. It has since been used in the Calgary compression garment trial, exercise studies in post-COVID POTS, and a growing list of others. You rate nine symptoms from 0 (absent) to 10 (the worst you have experienced) for how you feel right now. The total runs from 0 to 90.

Unlike the weekly Malmö POTS score or the broader COMPASS-31, the VOSS is a snapshot. In trials it is completed at the end of a 10-minute stand or tilt, which makes it a natural companion to the NASA lean test: rate your symptoms at the end of the standing phase and you have a symptom number to sit alongside the heart-rate numbers. Rated lying down and again after standing, the difference shows how much standing itself drives your symptoms.

This is not a diagnostic tool. The VOSS has no validated cut-off and no formal validation study; it is used in research as a change measure. Healthy people report symptoms after a prolonged tilt too, so a non-zero score is expected. It cannot tell POTS apart from other causes of orthostatic symptoms. Discuss your results with your doctor. Based on: Raj SR, Black BK, Biaggioni I, Harris PA, Robertson D. Acetylcholinesterase inhibition improves tachycardia in postural tachycardia syndrome. Circulation. 2005;111(21):2734–2740; and Raj SR, et al. Propranolol decreases tachycardia and improves symptoms in POTS: less is more. Circulation. 2009;120(9):725–734. Instruction wording on this page is our own; the score is described in those papers rather than distributed as a form.

When are you rating these symptoms?

Rate how severe each symptom is right now, where 0 = absent and 10 = the worst you have experienced.

Mental clouding (brain fog, difficulty thinking clearly)

Blurred vision

Shortness of breath

Rapid heartbeat

Tremulousness (shakiness)

Chest discomfort

Headache

Lightheadedness

Nausea

Understanding your VOSS score

What the score measures

The VOSS is a nine-symptom rating used in POTS research, first by the Vanderbilt Autonomic Dysfunction Center. You rate mental clouding, blurred vision, shortness of breath, rapid heartbeat, tremulousness, chest discomfort, headache, lightheadedness and nausea from 0 (absent) to 10 for how you feel right now. The total runs from 0 to 90. Trials usually ask for it at the end of a stand or tilt.

It first appeared in Vanderbilt drug trials (Raj et al. 2005; Raj et al. 2009). Because it is a snapshot, this page records when you rated it and only compares results rated the same way.

The VOSS rates how you feel at one moment, usually while upright, so it pairs with a NASA lean test or tilt on the day. The Malmö POTS score covers the past 7 days, and the COMPASS-31 covers symptoms across six areas of autonomic function.

Score bands

There is no validated cut-off. As rough reference points, 27 healthy adults averaged 12 at the end of 10 minutes of tilt, and 18 women with POTS had a median of 35 at the end of a 10-minute stand. Scores depend heavily on when and how you are rated, so compare your own results under the same conditions rather than against these figures.

VOSS totals reported in published studies
GroupWhen ratedPeopleTotalSource
Healthy adultsEnd of 10 minutes of tilt27Average 12 (SD 12)Pereira and Edgell 2025
POTSBefore a dose of propranolol or placebo, in a trial clinic36Median 17Raj et al. 2009
POTSEnd of a 10-minute stand, no compression18Median 35Bourne et al. 2026

What a change in score means

No minimal important change has been published. In trials, treatments that helped lowered the total by roughly 4 to 11 points more than placebo or no treatment, but those were group averages measured in a clinic. For your own tracking, a change that repeats across several ratings made the same way is more likely to be real.

Keep the conditions the same each time: time of day, posture and time standing. Rating at rest and again at the end of a stand shows how much standing adds. The stand test logger can hold the matching heart rate readings.

What it does not measure

No. It has no validated cut-off and has not had a formal validation study. Healthy people report some symptoms after 10 minutes upright too. POTS is diagnosed from a sustained heart rate rise on standing or tilt, with symptoms, once other causes have been ruled out.

The authors of a 2024 breathing study note that the VOSS lacks psychometric validation and that one number can hide symptoms that change during the stand (Stick et al. 2024). For heart rate, use the NASA lean test and the 30 bpm threshold explainer.

Taking this to your GP or consultant

Bring the total, the date, how you rated it and the heart rate readings from the same stand. A pair of ratings, at rest and after 10 minutes upright, says more than one number. Describe the VOSS as a nine-symptom rating used in POTS treatment trials. It shows how much standing affects you and whether that changes with treatment, but it is not a diagnostic test. See preparing for a GP appointment.

Sources