Functional outcome measures in haemophilia : a systematic review

• Main Author: Wijesekera, M.
• Published: University of Liverpool 2017
• Subjects: 616.1
• Online Access: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.722071

Background: Haemophilia is an inherited bleeding disorder that results in haemarthrosis leading to chronic arthropathy in those with severe forms of the disease. It causes significant disability and affects a patient’s quality of life. Functional outcome measures enable the healthcare professionals to assess the patients’ ability to carry out activities of daily living providing an important input to the assessment of joint disease. Objectives: This study aims to carry out a systematic review to identify the existing functional outcome measures used in the adult English speaking, haemophiliac population and evaluate these instruments based on their development methodology, measurement properties and other properties. Methods: Both PubMed and Scopus databases were searched to identify suitable outcome measures. Once the search identified the instruments, each instrument was searched to identify the relevant pilot and validation studies. Development methodology of each instrument was summarised. The measurement properties were evaluated using the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) 4-point checklist. These measurement properties included internal consistency, reliability, measurement error, construct validity, criterion validity, content validity and responsiveness. The other properties that were assessed include interpretability, generalisability, precision, conceptual model, measurement model, acceptability, feasibility and burden. Results: There were three main outcome measures used to assess function in the adult haemophiliac population. These were the Haemophilia Activities List (HAL), the Functional Independence Score in Haemophilia (FISH) and the Haemophilia Exercise Project–Test- Questionnaire (HEP-Test-Q). Information on the development of instruments was only well provided in the HAL. However the COSMIN checklist proved that the HAL had not assessed all measurement properties. The FISH and the HEP-Test-Q, did not possess very good methodological quality of its measurement properties. With regards to the other properties, all three instruments were acceptable but interpretability was poor. The HAL and the HEP-Test- Q were precise. The conceptual model instruments assessed function in different forms, whereas the measurement model was treated as a reflective model in all three instruments. The HEP-Test-Q had the most amount of burden in comparison to the other instruments. The main limitation of this study was that the FISH, a performance based instrument was evaluated using the COSMIN checklist that was developed to assess patient reported outcomes. Conclusion: This systematic review suggests that the existing instruments produced to assess function in adult persons with haemophilia have not been adequately validated and that the methodology undertaken for this process consists of certain drawbacks. This suggests that there is scope for a new instrument to assess function in the English speaking adult haemophiliac population.