Normative data of the EORTC QLQ-C30 for the German population: a population-based survey

The aim of the present study was to generate up-to-date normative data for health-related quality of life (QoL) measured with the "European Organization for Research and Treatment of Cancer (EORTC) Core Quality of Life Questionnaire (QLQ-C30)" in a random sample of the population in Northern Germany.

We conducted a population-based survey of a random sample of 10,000 persons aged 16 years or older. The postal questionnaire included questions regarding lifetime prevalence of common diseases and quality of life. EORTC QLQ-C30 scales were scored according to standard procedures. The results were stratified for age and sex.

The questionnaire was completed by 4,684 (47%) of 9,928 eligible persons. Mean age of the participants was 51.7 years (standard deviation: 18.5) and 57% were females. Missing values for the EORTC QLQ-C30 scales and items were sparse (minimum: 0.2%, maximum: 1.5%). Self-reported health related QoL varied by age and sex. Generally, men reported better functioning and fewer symptoms than women. In both sexes function declined and symptoms increased with increasing age. Symptoms most frequently reported were fatigue, pain and insomnia. Compared to the German reference data published in 2001 our participants scored more than 10 points higher on the latter three scales/items. The most frequently reported diseases were hypertension (36%), hyperlipidemia (26%) and arthritis (30%). Lifetime prevalence of depression was 16% in women and 11% in men.

Our study participants are representative for the German general population with regard to age, sex and education. Of special interest is the high proportion of participants reporting depression which is also mirrored by high fatigue, pain and insomnia scores. The normative data provided should be used as comparison health-related QoL data when evaluating the QoL in German cancer patients.