Initial Validation and Psychometric Properties of the Croatian Version of the Pieper–Zulkowski Pressure Ulcer Knowledge Test

<b>Background</b>: Understanding and preventing pressure ulcers is a key aspect of healthcare, with nurses playing a crucial role in their management and prevention through education and clinical practice to improve patient outcomes. <b>Objectives</b>: This quantitative, psychometric, cross-sectional study aimed to translate and culturally adapt the Pieper-Zulkowski Pressure Ulcer Knowledge Test and to evaluate the psychometric properties of the Croatian version of this measurement instrument. <b>Methods</b>: A study was conducted in a state hospital in Šibenik, Croatia, on a sample of 268 participants. <b>Results</b>: The content validity of the instrument, with an S-CVI of 0.981, indicates excellent validity, while its internal consistency is acceptable, as reflected in an overall KR-20 of 0.79. The maximum split-half reliability is 0.87 and Guttman Lambda 6 reaches 0.89, indicating excellent internal consistency. The overall test-retest reliability is excellent (ICC = 0.91), with the Prevention subscale showing the highest reliability (ICC = 0.88), followed by Staging (ICC = 0.86) and Wound Description (ICC = 0.84). Item-level difficulty and discrimination index were also calculated. <b>Conclusions</b>: The adapted, translated, and validated questionnaire represents a valuable tool for measuring knowledge about pressure ulcers among healthcare professionals, suitable for use in Croatian society. This instrument can be used to assess knowledge in clinical settings and evaluate the effectiveness of educational programs, providing valuable insights into the education and professional competence development of healthcare professionals.