title: Relationship between assessment item format and item performance characteristics.
abstract: OBJECTIVE
  To evaluate the relationship between assessment item formats (case-based versus noncase-based) and item performance characteristics.
  
  
  METHODS
  Assessment items (1,575) were collected from examinations administered in several therapeutics courses over 4 academic years. Items were categorized as either "case-based" or "noncase-based" and item performance characteristics (discrimination index and level of difficulty) were evaluated.
  
  
  RESULTS
  Noncase-based items represented approximately three-fourths of all items that were evaluated, and demonstrated a higher discrimination index than case-based items. Case-based items were generally lengthier and included more detailed information than noncase-based items; however, they were not more difficult and exhibited a lower discrimination index. Secondary analyses revealed that 5-foil multiple-choice items are more difficult and have a higher discrimination index compared to 4-foil items.
  
  
  CONCLUSIONS
  The format used for an examination/test item (case-based or noncase-based) has an impact on item performance characteristics.
authors.affiliation: Bernard J. Dunn School of Pharmacy, Shenandoah University, Nashville, TN 37204, USA. steve.phipps@lipscomb.edu
authors.forename: Stephen D
authors.initials: SD
authors.lastname: Phipps
authors.forename: Marcia L
authors.initials: ML
authors.lastname: Brackbill
mesh_terms: D032882:Comprehension; D016002:Discriminant Analysis; D004512:Education, Pharmacy / Q000379:methods*; D004521:Educational Measurement / Q000379:methods*; D006801:Humans; D018794:Problem-Based Learning; D011594:Psychometrics