Between standards and practice: a cross-sectional comparative study of self-assessed nursing professional competence in Poland and Lithuania using interaction-based regression

The growing complexity of healthcare and expanding nursing roles require systematic assessment of professional competence across different healthcare contexts. This study aimed to assess self-reported nursing professional competence among participating nurses from Poland and Lithuania and to examine whether associations between demographic, educational, and workplace-related characteristics and self-assessed competence differed between the two country samples. A cross-sectional study was conducted among 851 professionally active nurses from Poland and Lithuania. Data were collected online using the Nurse Professional Competence Scale-Short Form (NPC-SF) and a sociodemographic questionnaire. Descriptive statistics, between-country analyses, adjusted linear regression models, and interaction-based regression analyses were applied. Nurses reported high self-assessed competence scores in direct nursing care and value-based practice, whereas the lowest scores were observed in Development, Leadership and Organization of Nursing Care and Medical and Technical Care. In unadjusted analyses, participants in the Polish sample scored higher in Nursing Care, whereas participants in the Lithuanian sample scored higher in Medical and Technical Care and Development, Leadership and Organization of Nursing Care. After adjustment for age, professional experience, workplace, education, and additional professional development, country remained significantly associated with five of six NPC-SF domains, but not with Nursing Care. Higher education was positively associated with NPC-SF scores in several domains. Associations of sex, age, education, workplace, and professional development with NPC-SF scores differed between the two country samples. Self-assessed competence profiles differed between the Polish and Lithuanian samples and were associated with individual and professional characteristics. Broader educational, professional, and organizational contexts may help explain these patterns; however, the observed associations do not demonstrate direct effects of national systems. Given the non-probability sampling strategy, the findings should be interpreted as sample-based comparative evidence on self-assessed competence among participating nurses. These findings support context-sensitive approaches to competence development.