Calibration of Hernia-Specific Patient-Reported Outcome Measures

Although there are many patient-reported outcome measures used for ventral hernia (VH), disease-specific instruments, such as the Hernia-related Quality-of-Life (QoL) Survey (HerQLes) and Abdominal Hernia-Q (AHQ), have shown greater accuracy in capturing all VH-related QoL. We present a novel calibration that allows providers to convert scores between the AHQ and HerQLes, enabling better unification of QoL data.

Patients with VH were prospectively identified and simultaneously administered both the AHQ and HerQLes pre- and post-operatively. To ensure the validity of the calibration, responses were excluded if patients answered instruments on different dates or if the responses were discordant on corresponding questions within each instrument. The calibration was estimated using a linear mixed effects model, including linear and quadratic scores, timing of survey relative to surgery and their interactions as fixed effects, and patients as random effects to account for multiple surveys from the same patient.

In total, 109 patients were included, responding to 300 pairs of surveys (112 preoperative and 188 postoperative), of which 17 (5.6%) were excluded because of discordant responses. Conversion of the HerQLes to AHQ was most accurate when including whether the survey was completed pre- or post-operatively, with a mean squared error of 0.0091. Similarly, converting the AHQ to HerQLes was most accurate when factoring in the timing of survey administration, with a mean squared error of 0.016.

We present a novel and accurate method to convert scores between the AHQ and HerQLes. Being able to unify QoL data from different PROMs supports efforts to more broadly integrate PROMs in surgery and to understand patient-defined measures of success.