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A limitation of the ICOAP is its reliability. The reliability of ICOAP is adequate
for use in groups of patients with hip OA, but not suffi cient to use in individual
patients. For patients with knee OA, the constant pain subscale does not have ade-
quate reliability for use in individual patients, while there are confl icting fi ndings
for the intermittent pain subscale. Accordingly, the minimal amount of change that
clinicians can consider to represent real change in the condition of a patient with
knee OA is high (MDC 90 : constant pain 35.8, intermittent pain 39.3, total 29 out of
100 [ 35 ]). This limits the ability of the ICOAP to detect smaller, real changes after
treatment with exercise, physical therapy, or pharmacology. The constant pain sub-
scale also has large fl oor effects, reducing its ability to detect deterioration in a
patient’s condition. While known measurement properties favor the use of the
ICOAP in patients with hip OA rather than knee OA, further evaluation of its mea-
surement properties is required in both knee and hip OA cohorts.
Osteoarthritis of Knee Hip Quality of Life (OAKHQOL)
The OAKHQOL was developed specifi cally to evaluate QoL in patients with knee
or hip OA [ 36 ]. It consists of 43 items across fi ve subscales (physical activities,
mental health, pain, social support, and social functioning) that are scored individu-
ally, as well as three supplementary items (professional activity, relationship with
partner, and sexual activity) [ 37 ]. A short version of the OAKHQOL was recently
developed to enhance the utility of the instrument. The Mini- OAKHQOL has 20
items that fi t within the same domains and includes the same three supplementary
items [ 38 ] (Table 10.2 ).
Patients complete the OAKHQOL and Mini-OAKHQOL independently, recall-
ing the previous 4 weeks when responding to each item. Completion time is
12–20 min for the full version, and less than 10 min for the short version. Clinicians
score the OAKHQOL and Mini-OAKHQOL manually, by calculating a mean item
score for each subscale, and report the score for each of the three supplementary
items individually. If 50 % or more of the items for an individual subscale are miss-
ing, the subscale score is not calculated. Scores are normalized to 0–100, with
higher scores representing better QOL. The OAKQHOL and Mini-OAKHQOL are
free to use in clinical settings. The items are presented in the development papers
(French [ 37 ], English [ 38 ]), although instructions for participants are not available
in English. Clinicians can email to receive the full version of the Mini-OAKHQOL
(Table 10.2 ). At this time, the OAKHQOL and Mini-OAKHQOL have not been
widely translated to other language versions.
Clinicians can be confi dent that the OAKQHOL and Mini-OAKHQOL subscales
measure the QOL dimensions that they intend to measure, and that all items within
the physical activities, pain, and mental health subscales measure the same con-
structs (Table 10.1 ).
The number of missing items associated with the full version of the OAKHQOL
can be high, especially for the supplementary items (>50 %). Clinicians may choose
to use the Mini-OAKHOL instead to minimize missing information. Although the
supplementary questions are likely to be relevant for some patients with knee or hip
N.J. Collins and E.M. Roos