Countdown From 100

Why we chose this test

This test has been chosen to capture changes in cognitive dysfunction. It is not as satisfactory as a test as the Neurological component of the Neuropsychological testing which we describe elsewhere (but which has to be carried out professionally), but it will capture deterioration or improvement. We would like to thank Dr Kenny de Meirleir (Professor of physiology and internal medicine at the Vrije Universiteit Brussel) for suggesting this test.

Examples of graphs generated


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You will need a stop watch (most mobile have one these days). Ask someone to time you counting down from 100 to 0 in units of 7. Make a note of the time it took in seconds.

Please do not practise this beforehand, nor in the interim period before you record your score again next time.
You should aim to do this before you embark on a new treatment and at the end of the treatment. If you are not embarking on any treatment, then perhaps every 6 months would enable you to track any incidental improvement.

More information


Next test – Fingerprints, or start recording your own data

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