U.S. hemophiliacs who use patient-reported outcome (PRO) instruments can provide reliable information on their disease burden, finds a new study that appeared in the journal Patient Preference and Adherence.
In the study, “Reliability of patient-reported outcome instruments in US adults with hemophilia: the Pain, Functional Impairment and Quality of life (P-FiQ) study” the research team assessed the reliability of five PRO instruments in patients with hemophilia.
“Given the current lack of consensus on assessing pain and associated functional impairment, validating at least one scale may help provide support for using these PRO instruments in clinical practice and assessment of research study cohorts,” researchers wrote.
Pain is a key symptom in hemophilia — not only for what it may represent in terms of the disease’s underlying biological mechanism, but also for its huge impact on quality of life.
Clinical and care teams can use several tools to determine pain burden. But information is limited on how these instruments can really reflect the disease burden among hemophiliacs.
The P-FiQ study (NCT01988532), which was supported by Novo Nordisk, included 164 adults with hemophilia A or B who had a history of joint pain or bleeding. The patients were asked to respond to five PRO instruments before and after a routine care visit, while they were in a non-bleeding state.
The PRO instruments tested were the EQ-5D-5L, a scale that measures health outcome; the Brief Pain Inventory v2 (BPI); the International Physical Activity Questionnaire (IPAQ); Short Form 36 Health Survey v2 (SF-36v2); and the Hemophilia Activities List (HAL).
“Each scale provides a different level of detail in describing the impact of hemophilia on pain and function in relation to both the number of questions and how specific they are,” researchers said.
The test-retest approach showed that for almost all PRO tools analyzed, the results between the first and second time patients answered were quite similar. The IPAQ test showed the highest concordance (100%) and the BPI the lowest (58.9%). Further statistical analysis confirmed that all five PRO instruments provided reliable results with different representations of disease burden in adult hemophiliacs.
“The choice of instrument to be used for research or clinical care should be driven by instrument characteristics other than reliability,” researchers wrote. “Specific instruments should be tailored to the study design or clinical need for specific outcome assessment.”