EQ-VAS overall-health score showed substantial proxy-interpreter agreement (ICC-CCC 0.78) after arthroplasty

Description #

The EQ-VAS (patient's overall self-rated health on a 0–100 visual scale) showed substantial agreement between interpreter-proxy and healthcare-interpreter administration: ICC = 0.78 (95% CI 0.68–0.85) and CCC = 0.78 (95% CI 0.68–0.85), with a mean difference of 0.72 points on the 0–100 scale (Table 3, Fig. 3). This was the smallest of the continuous-scale agreement coefficients and had the widest Bland-Altman limits relative to range (−22.7 to 24.1).

"EQ-VAS - 0.78 (0.68-0.85) 0.78 (0.68 - 0.85) 0.72 -22.7 to 24.1 0.79" (Xue, 2019, p. 5, Table 3)

"The Bland-Altman plots (Figs. 5 and 6) show that relative to the total score range for each measure, the limits of agreement are narrower for the Oxford score compared with EQ-VAS." (Xue, 2019, p. 4)

Methods Context #

What? #ⓘ

The observable: agreement between the two administration methods on the EQ-VAS, the patient's self-rated overall health from 0 (worst) to 100 (best), treated as continuous data.

"The EQ-VAS rates the patient's overall health along a visual scale from zero to 100 where zero refers to the worst health and 100 the best health." (Xue, 2019, p. 3)

How? #ⓘ

The EQ-VAS was treated as continuous and analysed with ICC and CCC on the paired proxy/interpreter scores from each participant's two randomised interviews. See A-0009ArtifactA-0009Initial AI draftInterpreter proxy survey administration (family or carer, 2-way telephone)A pragmatic, low-cost method for administering patient-reported outcome surveys by telephone to LEP patients, using the patient's own family member or carer as the interpreter proxy in place of a certified professional h….

"The EQ-VAS was treated as continuous data and was analysed using ICC and CCC." (Xue, 2019, p. 3)

Who? #ⓘ

85 LEP hip or knee arthroplasty patients at their routine 6-month registry follow-up.

"Eighty-five patients successfully received both methods of follow-up calls and were included in the data analysis." (Xue, 2019, p. 3)

Other Notes #

The mean difference of 0.72 (on 0–100) is the largest absolute mean difference reported and corresponds to the abstract's upper bound ("0.72 (score range of 0–100)").

Caveats #

• English-version surveys (not language-specific translations) plus variable proxy linguistic skill may have affected accuracy The validated surveys were administered in their English versions and translated on the fly by the interpreter or proxy, rather than using language-specific validated translations. Because of this, variation in the linguistic skill of the (untrained) proxy interpreters may have affected accuracy — an uncontrolled source of measurement error that could inflate or deflate the observed agreement.