KLK3 and posterior cortical atrophy: However, there is no national recommendation in Sweden for PSA-based PCa screening and the annual proportion of men aged 55–69 years who underwent a PSA test in the two study counties between 1997 and 2007 is estimated to be between 0% and 7% (Jonsson et al, 2011); thus, any bias introduced by PSA testing should be of limited relevance in our data.