P²I² uses PROMIS measures. These are scored on the T-score metric. High scores mean more of the concept being measured

**T-score Metric**

PROMIS, Neuro-QoL™, ASCQ-Me®, and many of the NIH Toolbox® measures use a T-score metric in which 50 is the mean of a relevant reference population and 10 is the standard deviation (SD) of that population.

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*On the T-score metric:*

A score of 40 is one SD lower than the mean of the reference population.

A score of 60 is one SD higher than the mean of the reference population.

**Direction of Scores**

For PROMIS measures, higher scores equals more of the concept being measured (e.g., more Fatigue, more Physical Function). Thus a score of 60 is one standard deviation above the average referenced population. This could be a desirable or undesirable outcome, depending upon the concept being measured.