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Patient-Reported Outcome Measures for Patients
with Osteoarthritis
Health professionals can use guidelines provided by OMERACT (“Outcome
Measures in Rheumatology”) to select PROMs that are most appropriate for patients
with OA. Originally developed to guide selection of PROMs for clinical trials, the
OMERACT Core Domain Set highlights elements that are important for patients
with the condition of interest. For knee, hip, and hand OA, the most important core
domains appropriate to PROMs are pain, physical function, and patient global assess-
ment, while health-related quality of life (HRQOL) is strongly recommended [ 9 ].
There are a number of generic PROMs that are appropriate to measure the core
domains in patients with OA. Visual analogue scales (VAS) and numeric rating
scales (NRS) are commonly used to evaluate pain severity. In the absence of an
established measure of global assessment, it is recommended that a single question
be asked, using a VAS or Likert scale [ 10 – 12 ]. For example, clinicians could ask,
“Considering all the ways your [knee] OA affects you, how have you been during the
past [time frame]?” [ 11 ] It should be kept in mind, though, that the use of a single-
item PROM can infl uence the reliability of the instrument. In measuring HRQOL,
we encourage the reader to also consider generic quality of life (QOL) PROMs that
can be used for multiple conditions, such as the EQ-5D ( http://www.euroqol.org ), Short
Form-12 (SF-12) [ 13 ], Short Form-36 (SF-36) [ 14 ], and the Assessment of Quality
of Life (AQoL) instrument [ 15 ]. However, it should be considered that little informa-
tion is available regarding their measurement properties in patients with OA.
This chapter focuses on PROMs for knee, hip, and hand OA, as these are most
commonly seen in the clinic. Examples of PROMs for other joints are listed at the
end of the chapter. We have selected PROMs based on their fi t with the OMERACT
Core Domain Set. Where possible, we have focused on measures that were devel-
oped specifi cally for OA in the target joint to ensure that the content is relevant for
patients. Because measurement properties are condition-specifi c and context-specifi c,
where possible we present measurement properties that are specifi c to the joint and
context (e.g., natural course or type of treatment) under study. The reader is encour-
aged to consider that not all measurement properties have been evaluated for all
PROMs, and that the absence of evidence for particular measurement properties
means that conclusions regarding these cannot be made at this time. For clarifi ca-
tion regarding whether such evidence exists, we direct the reader to Table 10.1.
Patient-Reported Outcome Measures for Knee and Hip
Osteoarthritis
Because the hip and knee undergo high loads during weight-bearing tasks such as
gait, knee, and hip OA have a substantial impact on functional mobility. This limits
an individual’s ability to perform daily activities, occupational tasks, and exercise.
10 PROMs for Osteoarthritis