Haemo-Adhaesione: A New Measure of Adherence for Adolescent and Adult Patients with Haemophilia

PURPOSE: To build a multidimensional questionnaire of adherence for a patient with hemophilia that includes not only clinical but also psychosocial aspects. PATIENTS AND METHODS: One hundred and forty-six patients with haemophilia (A and B) were recruited from several Hemophilia Treatment Centers for this study. The recruitment was performed through a personal interview (20–25 mins for each patient). A literature review was carried out (different databases). In the first version (136 items), all items were subjected to an external judgment (experts in hemophilia) and also presented and discussed with a group of patients. It was made a study of content validity and homogeneity index and reliability coefficients of score were calculated with an alpha coefficient. Empirical validation was made with Pearson correlation. RESULTS: The Haemo-Adhaesione scale was composed of 5 dimensions and 10 questions about basic haemophilia concepts. It was shown to be valid and reliable to assess adherence in the Spanish population. Its internal consistency was good in all dimensions. The Rasch model was used to confirm the multidimensional structure of the scale. Significant and negative correlations were observed with the VERITAS-Pro and VERITAS-PRN scale in all dimensions, and in the total score. CONCLUSIONS: The Haemo-Adhaesione scale is a good measure of adherence for PWH. Its multidimensional structure favors the inclusion of the objective and subjective aspects implicit in its definition, as well as its dynamic nature. Patients with greater adherence are those who have more awareness of their disease, and as a result, they are more compliant with prescription and their self-care. It also discriminates between patients who follow one treatment or another.