Implementation of the Patient Dignity Inventory in palliative care: adaptation of the Polish version

Background: The sense of dignity is subjective and interpersonal, shaping individual experience at every stage of life. In the case of terminally ill patients, the sense of dignity is determined by both external factors (changes in their social role) and internal factors (changes in their life priorities and capacities). The aim of this study was the evaluation of psychometric characteristics and cross-cultural adaptation of the Patient Dignity Inventory (PDI) in Poland, as well as verification of the clinical utility of the PDI in a group of Polish patients with advanced cancer receiving palliative care. Methods: The study included 80 patients aged 18 years and older, receiving inpatient palliative care in Poland. The construct validity of the PDI was assessed using the principal component analysis (PCA) with Promax rotation. The reliability of the scale in terms of its internal consistency was investigated using Cronbach’s alpha coefficient, along with an item-total correlation analysis using Kline’s criterion. Results: Principal component analysis for 25 Patient Dignity Inventory items revealed 3 components with eigenvalues greater than 1, explaining 74% of the total variance. However, PCA with a forced number of 5 factors revealed the factor structure, which resembled the original one to a greater extent. The reliability of the total score and the PDI in this Polish sample was 0.97. Conclusions: The Patient Dignity Inventory questionnaire is a valid and reliable tool for measuring the sense of dignity in Polish patients; it takes into account the comprehensive well-being of patients at the end of their lives, and helps gauge their adaptation to death.