Which linking table should I use?

​Each instrument pair was linked using different methods. All tables are provided in the full reports. We suggest that you use the IRT Fixed Parameter Calibration linking tables. Find the table with “Recommended” in the title.

My set of measures was linked using two different datasets. Which one should I use?

​Sometimes we had access to multiple datasets that included the same instrument pair. For example, both the MASQ and PROMIS Anxiety instrument were collected as part of testing in PROMIS and NIH Toolbox. When this happened, we created linking tables based on each dataset.

This resulted in two IRT linking tables for pairs like MASQ and PROMIS Anxiety. We recommend using the linking table from the PROMIS dataset.

How do I use a linking table?

​To use a linking table, start with your current measure and score it as you normally would in accordance with accepted scoring conventions. For example, for the SF-36, you sum raw scores on a subset of items to produce a mental health score.

Find the instrument’s score on the appropriate PROsetta Stone table and its corresponding PROMIS score. In some cases, the direction of scores between the two instruments is opposite (e.g., high scores are good on one instrument and bad on another instrument). You do not need to change the direction of scores – just use the tables as-is. It will provide the correct PROMIS score.

Note that each report (the link to the right of the table link) has a paragraph that clarifies the score direction of each instrument and what high/lower scores mean.