Detailled Information

Jackson CE, Barohn RJ, Gronseth G, Pandya S, Herbelin L. Muscle Study Group. Inclusion body myositis functional rating scale: a reliable and valid measure of disease severity. Muscle Nerve 2008;37(4): 473–476.

Psychometric validation of a patient-reported measure of physical functioning in sporadic inclusion body myositis.

Development of the sporadic inclusion body myositis physical functioning assessment. 

Investigation of the psychometric properties of the inclusion body myositis functional rating scale with rasch analysis.

The Inclusion Body Myositis Functional Rating Scale (IBMRFS) is a 10-item clinician-rated ordinal scale developed for people with inclusion body myositis. It is an administered ordinal rating scale used to determine patients’ assessment of their capabilities and independence that has been developed through modification of the Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS) to create a disease-specific functional scale for IBM by Jackson and colleagues. The IBM-FRS addresses swallowing, handwriting, cutting food, handling utensils, dressing, hygiene, turning in bed, adjusting covers, sit to stand, walking and climbing stairs. The IBM-FRS did not include patients on its development. To address this gap and the unique experiences of patients with sIBM, the sIBM Physical Functioning Assessment (sIFA) was developed to assess the clinical progression and impact of sIBM on physical functioning and the potential benefit of new therapies in a clinical trial setting.

A function score from 0 to, with 4 being normal and 0 being unable to perform, for each of the 10 domains is added.

For the sIFA, each item employs an 11-point numerical rating scale ranging from 0 (no difficulty) to 10 (unable to do).