DRC’s Psychometric Services team is staffed with highly-credentialed psychometricians and measurement professionals that design programs to meet the expanding psychometric requirements of next-generation assessments.
DRC offers a complete range of psychometric services and quality controls, and builds customized testing solutions that adhere to the Standards for Educational and Psychological Testing (AERA, APA, NCME, 1999). We have provided psychometric services for assessment programs in Alabama, Alaska, Arkansas, Georgia, Idaho, Louisiana, Minnesota, Nebraska, North Carolina, Ohio, Oklahoma, Pennsylvania, South Carolina, and Washington. Beyond good design and implementation, a testing program’s success hinges on communicating results quickly, accurately, and clearly. DRC Psychometricians have extensive experience in psychometric analyses, research, and reporting.
Some of the psychometric services we provide are summarized below.
Calibrating, Scaling, and Equating: DRC’s psychometricians have multiple years of experience calibrating, scaling, and equating assessments based on multiple IRT models including Rasch and the Three Parameter Logistics Model.
Raw-to-Scale Score Conversion Tables: DRC Psychometric Services team produces valid and reliable raw-to-scale score conversion tables.
Standard Setting/Standard Validation: Our psychometricians have conducted standard setting studies using examinee- and test- centered models. Examinee-centered models used include Body of Work, Borderline and Contrasting Group methods. Test-centered models have included Modified Angoff and Bookmark. DRC Psychometric Services team has also used examinee- and test- centered models combined to obtain cut score information.
Psychometric Software Applications: DRC has developed and refined our own state-of-the-art psychometric software tools to ensure efficient, error-free forms construction and item analysis, including the following:
PERFORM, DRC’s proprietary technology-based infrastructure for test assembly, enables us to narrow the set of possible test forms to a manageable subset of psychometrically acceptable forms while adhering to industry best practices
iTEMs, DRC’s proprietary software for classical item and test analysis, enables us to quickly and effectively analyze items and flag statistics using custom criterion
Residual Analysis Tool, A tool based on published work, created in Excel and developed by DRC, to allow state, district, and school personnel to analyze residual patterns. Residuals are the difference between observed and expected scores for subgroups of people and provide information about instruction and curriculum.
DRC’s Psychometric Services team also offers these services:
Test security/data forensic analysis
Item and scale drift analysis
Other defined special studies, including:
Item order effects