Abstract
Background/Objectives: This cross-sectional study aimed to produce an adapted Croatian version of the Negative Behaviors in Health Care Questionnaire and to validate it. Methods: The process comprised the translation, cultural adaptation, and psychometric evaluation of the questionnaire. Clinical specialists and qualified bilingual speakers participated in both forward and backward translation. Face validity was tested. The survey's original developer approved the final version. The reliability of the questionnaire was assessed using the test-retest method and Cronbach's alpha coefficient. Exploratory and confirmatory factor analyses and assessments of divergent and convergent validity were conducted. The collected data were analyzed using SPSS 21.0 and R, program version 3.5.2., for Windows. Results: A five-factor structure was obtained and confirmed via CFA, although not all fit coefficients were satisfactory. The internal consistency reliability was 0.86 for the contributing factors and the seriousness of aggression, 0.79 for the use of aggression, 0.95 for the fear of retaliation, and 0.83 for the frequency of aggression; in total, α = 0.88. Test-retest reliability was moderate. All correlations were statistically significant, and the correlation was the highest for seriousness (0.754) and frequency of aggression (0.725) and the lowest for contributing factors (0.528). Test-retest reliability was satisfactory. Statistically significant differences were found when comparing respondents by gender, age, work experience, education, and hierarchical position. Conclusions: The adapted, translated, and validated survey provides a valuable tool for assessing lateral and vertical aggression between and towards nurses in terms of contributing factors, frequency, severity, uses of aggression, and fear of retaliation.