Item Analysis of the Modified Version of the Routine Blood Transfusion Knowledge Questionnaire

Background and Purpose: Item analysis is important in examining the quality of items. The main aims of this sub-study were to assess and improve the psychometric properties of the modified version of the Routine Blood Transfusion Knowledge Questionnaire (RBTKQ-2) and produce an optimized version (RBTKQ-O) of it. Methods: Statistical item analysis was performed on the RBTKQ-2 after completion by 305 nurses. Results: There were one (3%) easy, 15 (47%) moderately difficult, and 16 (50%) difficult items. Twenty six (81%) items and six (19%) had positive significant and weak point-biserial correlation respectively. The majority of distractors (n = 66, 64%) were functional. Four sources of information, including item analysis data, informed the development of the RBTKQ-O. Conclusions: The RBTKQ-O addressed the limitations that were identified in the versions published earlier. This version can be used by researchers and academics worldwide.