Minimally important differences for interpreting European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 scores in patients with head and neck cancer

Abstract

Background: We aimed to estimate minimally important difference (MID) for interpreting group-level change over time for European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire core 30 (EORTC QLQ-C30) scores in head and neck cancer. Methods: Data were derived retrospectively from two published EORTC trials. Clinical anchors were selected using correlation strength and clinical plausibility of the given anchor/QLQ-C30 scale pair. MIDs for within-group and

Minimally important differences for the EORTC QLQ-C30 in prostate cancer clinical trials

“…anchor scores indicating a low health status were associated with lower HRQOL scores). This compares well to MIDs already developed in this EORTC project for head and neck cancer [ 22 ], advanced breast cancer [ 21 ], malignant melanoma [ 20 ], colorectal [ 23 ] and ovarian [ 24 ] as well as to other similar research [ 26 – 28 ]. With two exceptions (global quality of life, diarrhoea), these MIDs were larger for deterioration compared to improvements.…”

“…This aligns with existing findings even beyond the QLQ-C30 [ 17 , 20 , 21 ], suggesting that patients may have a higher sensitivity to favourable differences [ 26 , 29 , 30 ]. However this effect is not universal as other studies have reported no systematic differences in the magnitude of change between deteriorating and improving scores [ 15 , 19 , 22 ].…”

Minimally important differences for interpreting European Organisation for Research and Treatment of Cancer (EORTC) Quality of life Questionnaire core 30 scores in patients with ovarian cancer

“…Generally, MIDs for most scales were within the range of 4-10 points, which is similar to the 5-10 point range reported by Osoba et al [3] in breast and small-cell lung cancer. A similar range was also observed by Cocks et al [4] in pooled data across multiple cancer sites, by Musoro et al [6,12,14,15] in malignant melanoma, advanced breast cancer and head and neck cancer respectively, and by Maringwa et al [7,8] in lung and brain cancer respectively. We observed that MIDs for deterioration were lower than those for improvement, except for the diarrhoea scale.…”

“…This rule mainly stems from overlaps in initial guidelines by King [2] and Osoba et al [3] for interpreting the EORTC QLQ-C30. However, there is increasing evidence that MIDs can vary by EORTC QLQ-C30 scales, direction of change (improvement/deterioration) and clinical settings [4,6,7,12,14]. This implies that a global rule for MIDs applicable to all settings is highly unlikely [13].…”

“…Focus is on establishing MIDs for interpreting HRQOL change scores over time in groups of ovarian cancer patients. This work is part of the EORTC MID project that seeks to gather empirical evidence on patterns of MID estimates across EORTC QLQ-C30 scales and disease sites [6,12,14,15,16]. Our study differs from Osoba et al [2] in that we used clinical anchors whereas Osoba used patient-derived ratings.…”