Comparison between Swedish EORTC QLQ-C30 general population norm data published in 2000 and 2019

Background: Normative health-related quality of life (HRQoL) data from the general population are regularly used to facilitate the interpretation of HRQoL as reported by cancer patients participating in cancer clinical trials, especially when conducting long-term follow-up studies after treatment. The aim of the present study is to compare two Swedish normative data sets, published in 2000 and 2019 respectively, and explore whether HRQoL as reported by the Swedish general population has changed over time.

Material and methods: 'Sample 2000' was comprised of normative data from the Swedish general population who responded to the EORTC QLQ-C30 in a Swedish mail survey in 1999 (n = 3069). 'Sample 2019' consisted of data from the Swedish general population collected as part of a European norm data study using online panels, published in 2019 (n = 1027). Data were analyzed stratified by sex and age (40-49; 50-59; 60-69; 70-79 years).

Results: For most of the subscales and single items, no age group differences between the two samples were found, with the exception of the oldest age group (70-79 years), where Sample 2019 generally showed better HRQoL as compared to Sample 2000. Lower (worse) levels of Global quality of life and higher (worse) levels of Dyspnoea were found in Sample 2019 for most age groups.

Conclusion: There were no differences found between the samples for most EORTC QLQ-C30 subscales and single items, with the exception of the oldest age group of both sexes in Sample 2019 who reported better HRQoL on many variables. When deciding which normative dataset to use, the mode of data collection and age group have to be considered.