Perception of late effects among long-term survivors after haematopoietic stem cell transplantation: Descriptive analysis and validation of the Brief Illness Perception Questionnaire. A sub-study of the PROVIVO study

To give a first description of the perception of late effects among long-term survivors after Allogeneic Haematopoietic Stem Cell Transplantation (HSCT) and to validate the German Brief Illness Perception Questionnaire (BIPQ).; This is a secondary analysis of data from the cross-sectional, mixed-method PROVIVO study, which included 376 survivors from two Swiss HSCT-centres. First, we analysed the sample characteristics and the distribution for each BIPQ item. Secondly, we tested three validity types following the American Educational Research Association (AERA)Standards: content validity indices (CVIs) were assessed based on an expert survey (n = 9). A confirmatory factor analysis (CFA) explored the internal structure, and correlations tested the validity in relations to other variables including data from the Hospital Anxiety and Depression Scale (HADS), the number and burden of late effects and clinical variables.; In total, 319 HSCT recipients returned completed BIPQs. For this sample, the most feared threat for post-transplant life was long lasting late effects (median = 8/10). The expert-survey revealed an overall acceptable CVI (0.82), three items-on personal control, treatment control and causal representation-yielded low CVIs (<.78). The CFA confirmed that the BIPQ fits the underlying construct, the Common-Sense Model (CSM) (χ2 (df) = 956.321, p = 0.00). The HADS-scores correlated strongly with the item emotional representation (r = 0.648; r = 0.656).; According to its overall content validity, the German BIPQ is a promising instrument to gain deeper insights into patients' perceptions of HSCT late effects. However, as three items revealed potential problems, improvements and adaptions in translation are therefore required. Following these revisions, validity evidence should be re-examined through an in-depth patient survey.