You may not realize it, but not every item on an ARRT exam counts towards a pass/fail decision. The unscored items are called "pilots," and they undergo a test phase before we put them into regular use. Unlike basic algebra, medical imaging technology and procedures are constantly changing. For example, more R.T.s in radiography are using computed radiography these days, while fewer are using film-screen cassettes.1 Pilot items allow ARRT exams to adapt and reflect changes in the knowledge and skills that R.T.s need to practice.
It all begins with volunteer subject matter experts (SMEs) who write items on new technologies, procedures, and regulations in their field. However, these new items have never been tested. Although the exam committee reviewed the items to ensure they are relevant to entry-level practice, we don't know how difficult the item will be or whether it correlates with overall exam performance as it should. When enough candidates respond to the item, ARRT will review the item's performance and psychometric properties. For example, if too many candidates get the item wrong, the item's wording might be confusing. ARRT will also review the comments that candidates share about the item. If all goes well, we can then use the pilot item on future exams as a scored item (one that does count toward the pass/fail decision). Those that don't meet our statistical requirements aren't lost forever. We may return them to our SMEs for rework based on what we learned from the test before piloting them again. This process allows ARRT to keep the exam current with modern practice while ensuring the exam is fair to the candidate.
References
1.) ARRT (2022). Practice Analysis Report: Radiography.
