Determinants of non-response in a longitudinal study of participants in the Women and Alcohol in Gothenburg project

Longitudinal assessment is useful for tracking patterns of alcohol use over time. Non-response is a common feature of longitudinal design and can bias estimates of alcohol use if there exist systematic differences between respondents and non-respondents. We investigated whether alcohol use, health status, and sociodemographic characteristics were determinants of non-response in a longitudinal cohort of women in the general population. We used data from a stratified, random sample of 479 women born in 1925, 1935, 1945, 1955, 1965, and 829 women born in 1970 and 1975, who were initially selected as participants in the Women and Alcohol in Gothenburg project. Results from multivariable logistic regression revealed that problematic alcohol use, depression, poor self-rated physical health, and basic education were associated with increased odds of non-response among women born in 1925, 1935, 1945, 1955, and 1965. Among women born between 1970 and 1975, older age and being unmarried increased the odds of non-response at follow-up. Surprisingly, problematic alcohol use and poor health were not associated with non-response in these younger birth cohorts. This study finding suggests that approaches to improve future survey response rates need to consider factors of greatest relevance to birth year and age.The work was supported by the [Swedish Council for Social Research, Stockholm] under Grant [94-0130:1C] and [the Swedish Research Council for Health, Working Life and Welfare (Forte)] under Grant [2013-0632].