Interest in health screening as a predictor of long-term overall mortality: multilevel analysis of a Japanese national cohort study

Background: In Japan, screening programmes have been widely implemented as a public health practice. We investigated the effect of the area-level interest in health screening on mortality using data from a large cohort in Japan.

Methods: A baseline survey was conducted between 1988 and 1990 among 110,792 residents of 45 areas, aged 40-79 years. Area-level interest in health screening was defined as the proportion of people with high and moderate interest in health screening in an area. Multilevel Poisson regression was employed in a two-level structure of individuals nested within the areas. During 15 years of follow-up (1,035,617 person-years), 13,184 deaths were observed.

Results: The reduction in mortality rate was (a) 2% in both men (p=0.009) and women (p=0.038) for each percent increase in area-level interest in screening, and (b) 10% in men (p=0.001) and 9% in women (p=0.001) for individual attendance to screening in the year before follow-up. There was no interaction between area-level interest in screening, individual-level attendance at screening and overall mortality.

Conclusion: Area-level and individual interest for health screening appear to be independent predictor of 15-year mortality in this national Japanese study. The present findings may support public health practices to promote knowledge and participation in screening programmes.