ABSTRACT
BACKGROUND: Participants of the Longitudinal Urban Cohort Ageing Study (LUCAS) were recruited from patients 60 years and older from general practitioner's offices in Hamburg. This is different from the usual methods of drawing representative samples. OBJECTIVES: The research question addressed the comparability of LUCAS results with those from cross-sectional surveys with participants randomly chosen from a population list. Therefore, the LUCAS data collected in four waves during the first 12 years were compared with data (age, gender) from the Hamburg Statistics Office (HSO), and selected characteristics (socio-demography, health, mobility) from three representative cross-sectional surveys in older Hamburg citizens. METHODS: First, HSO data compiled in population pyramids for older men and women were compared with equivalent pyramids based on the LUCAS data at recruitment (2000/01) and in waves 2 to 4. Second, characteristics worded identically in the cross-sectional surveys and the simultaneous LUCAS waves were compared. RESULTS: The LUCAS population pyramids were in good accordance at all time points with those of the general older population in Hamburg (except ages 60-64 in men in 2000). Good comparability was also found for health related characteristics from the three representative studies and simultaneous LUCAS waves (e. g. need of nursing care in 2012: LUCAS 7.1 %; Hamburg 7.4 %). CONCLUSIONS: Information on health in old age generated periodically in the LUCAS cohort was largely comparable with that from representative cross-sectional studies and statistics registries. Older people are frequently under-represented in epidemiological studies. Therefore, the LUCAS data may provide useful information for Hamburg and similar metropolitan areas in Germany.