If you have arrived here from a search or from elsewhere on the site, you may not be sure which of the available tools is most relevant to you. This page is a brief guide to help you decide.

If your main concern is autonomic symptoms

If your main concern is autonomic symptoms (dizziness on standing, heart racing, temperature regulation problems, or gut dysfunction), start with the COMPASS-31. It is the most comprehensive autonomic symptom questionnaire available and gives you a structured, scored summary of symptom burden across six domains. It is particularly likely to be recognised by a specialist if you bring results to an appointment. It takes about 10 minutes.

COMPASS-31 questionnaire

If breathlessness is a significant symptom

The Nijmegen questionnaire screens for breathing pattern disorder and hyperventilation syndrome, a common and often underdiagnosed problem in post-viral conditions that can contribute to breathlessness, dizziness, brain fog, and chest tightness. It takes about 2 minutes.

Nijmegen questionnaire

If fatigue is dominating your life

The Fatigue Severity Scale (FSS) measures how much fatigue is interfering with your daily functioning. It is widely used in ME/CFS and long COVID research and is useful for tracking whether your functional fatigue is changing over time. It takes about 2 minutes.

Fatigue Severity Scale

If you want to check for excessive daytime sleepiness

The Epworth Sleepiness Scale measures your tendency to doze in everyday situations. Fatigue and sleepiness are not the same thing; a low ESS score alongside severe fatigue can be informative in itself. It takes about 2 minutes.

Epworth Sleepiness Scale

If you want a quick overall snapshot of your functional capacity

The Bell CFIDS Disability Scale gives you a single score from 0 to 100 based on a description of your activity level and symptom impact. It takes less than a minute and lends itself to regular tracking.

Bell CFIDS Disability Scale

If you suspect POTS or orthostatic intolerance

The NASA lean test guide walks you through an at-home standing test with a timer and heart rate logging. It is a practical way to gather objective data while waiting for formal autonomic testing, and the results can be useful to bring to appointments.

NASA lean test guide

Using more than one

You can complete more than one. For someone with a post-viral condition, a reasonable starting set might be the COMPASS-31 (autonomic symptoms), the FSS (fatigue impact), and the NASA lean test (orthostatic heart rate). Together, these give a fairly rounded picture of the areas most commonly affected.