Design, material and methods in the NORA study. Nordic Research on Ageing

Area of Science:

• Gerontology and Public Health
• Epidemiological Research Design
• Longitudinal Aging Studies

Background:

• Aging populations present complex challenges for public health and social services.
• Understanding regional variations in health and participation is crucial for targeted interventions.
• Longitudinal studies are essential for tracking health trajectories and mortality in older adults.

Purpose of the Study:

• To describe the research design and methodology of the Nordic Research on Ageing (NORA) study.
• To report response and participation rates at baseline (age 75) and follow-up (age 80) across three Nordic localities.
• To present mortality data and facilitate cross-locality comparisons in aging research.

Main Methods:

• The NORA study employed a longitudinal design, recruiting participants aged 75 in Göteborg, Glostrup, and Jyväskylä.
• Baseline data collection involved home interviews followed by standardized laboratory tests.
• A five-year follow-up study assessed participants at age 80, including interviews and further examinations.

Main Results:

• Baseline participation rates for interviews ranged from 82.5% to 92.9%, with laboratory test participation between 72.4% and 77.2%.
• Follow-up participation rates were 76.6% to 93.6% for interviews and 59.7% to 71.9% for tests.
• Mortality rates varied by locality, with Göteborg at 19.0% and Glostrup at 27.2% over the study period.

Conclusions:

• The NORA study successfully established a robust dataset for analyzing aging processes in different Nordic contexts.
• High participation rates at baseline and follow-up ensure the generalizability of findings.
• The collected data enable comprehensive descriptions and comparisons of aging across localities and over time.