The Norwegian Counties Public Health Survey (NCPHS): a design study.

Background: Effective public health initiatives should be founded on a comprehensive and robust understanding of health-related factors including societal and community contexts. The Norwegian Counties Public Health Survey (NCPHS) aims for insights into the adult population on topics relevant for planning public health practices at county and municipality levels.

Methods: The NCPHS includes a core questionnaire on public health-related topics and demographics, including indicators of socio-economy, with additional optional questions and scales varying across data collections. Samples are drawn from the Norwegian National Population Register and 'washed' against the Common Contact Register to retrieve digital contact information and exclude those who cannot be contacted electronically. NCPHS was piloted in 2015 and 2018 (four counties). After some revision of instruments and sampling procedures, surveys have been carried out in most Norwegian counties since 2019. The total number of participants has now passed 400,000.

Results: Expedient data analysis has enabled the Norwegian Institute of Public Health to present comprehensive reports within 6 weeks of completed data collections. In these, outcome variables are analysed against district (within counties), gender, age, educational attainment and self-reported sufficiency of household income. Tables are also made available at the municipality level.

Conclusions: The NCPHS represents a valuable addition to existing data sources, providing critical information for planning purposes for local and regional public health authorities, for assessing trends over time, comparisons across counties and regions and for evaluation of policies and interventions. The value of such a system during times of crisis was demonstrated during the COVID-19 pandemic.