How are the national comparative data available on the first day of administration calculated?

Since the second year of publication for End of Rotation exams, PAEA has provided members with projected national comparative data (means and standard deviations) on the first day of administration. These comparative data are based on the projected performance of a reference population of PA students and the historical performance of individual items included on the new forms. When the exam forms are retired, we then are able to report the final statistics for that version of the exam. All Historical Statistics can be found on the Assessment Resource page.  

 The method we used to make national comparative data available on the first day of administration is based on actual performance of a reference population of students who took previous End of Rotation exam forms. The reference group of each of the specialty exams were statistically equated from raw to theta to scale scores using a linear transformation. Utilizing empirical versus projected data in statistical analysis yields slightly different results but ensures that data are stable across years. To best represent our student test-takers, we felt it was important to transform raw scores into scale scores using empirical data.