The Leuven questionnaire for Patient Self-care during Chemotherapy (L-PaSC): instrument development and psychometric evaluation

Purpose: Since chemotherapy has largely become an outpatient treatment, adequate self-management is of great importance. Available instruments focus exclusively on dealing with side effects. However, self-care during chemotherapy not only concerns symptom self-management. The aim of this study was to develop a valid instrument to assess patient self-care during chemotherapy.

Method: First, we developed a topic list for our construct by performing a theory and literature review. Second, an expert panel of nine oncologists and oncology nurses evaluated content validity of the developing construct and its items using a triple Delphi procedure. A preliminary psychometric evaluation in 144 patients allowed identification and correction of items with poor psychometric properties. A convenience sample of 448 patients was used to evaluate item statistics (item difficulty), reliability (Cronbach alpha) and construct validity (exploratory factor analysis) of the final instrument.

Results: We developed a 22-item instrument with 7 themes expressing the most relevant aspects of patient self-care during chemotherapy. Seven items cover symptom self-management, while 15 items reflect other aspects of self-care during chemotherapy. Content validity was excellent (CVI = 0.78-1.00). Item difficulty index of the questions ranged from 0.17 to 0.89. Internal consistency is acceptable (Cronbach alpha = 0.76). Exploratory factor analysis defines two underlying factors: adhering to treatment recommendations and managing treatment-related negative events on the one hand, and relieving symptoms on the other hand.

Conclusions: The L-PaSC demonstrated good content validity and psychometric properties. The L-PaSC can be applied in research and clinical practice for evaluating patient self-care during chemotherapy.