Score production and quantitative methods used by the National Board of Chiropractic Examiners for postexam analyses

The National Board of Chiropractic Examiners (NBCE) uses a robust system for data analysis. The aim of this work is to introduce the reader to the process of score production and the quantitative methods used by the psychometrician and data analysts of the NBCE.

The NBCE employs data validation, diagnostic analyses, and item response theory-based modeling of responses to estimate test takers' abilities and item-related parameters. For this article, the authors generated 1303 synthetic item responses to 20 multiple-choice items with 4 response options to each item. These data were used to illustrate and explain the processes of data validation, diagnostic item analysis, and item calibration based on item response theory.

The diagnostic item analysis is presented for items 1 and 5 of the data set. The 3-parameter logistic item response theory model was used for calibration. Numerical and graphical results are presented and discussed.

Demands for data-driven decision making and evidence-based effectiveness create a need for objective measures to be used in educational program reviews and evaluations. Standardized test scores are often included in that array of objective measures. With this article, we offer transparency of score production used for NBCE testing.