What did you use as the mean to determine the scale scores, and why?

The statistical analysis of the means over time and equating of scale scores was completed by our psychometricians. PAEA used two primary criteria to select the best options for setting the scale:

1. the mean used should best represent a normally distributed base sample, and
2. the reference sample should be most representative of the current student population.

The mean that was selected to determine the scale was the mean score for the most recent year of complete data for each End of Rotation exam. These data provide an even distribution of scores and are the most recent representative picture of our current student population.

This standard will be reviewed every three to five years per best psychometric practices.