However, the improvement in adherence following retirement was significantly greater among employees with high job strain before retirement compared to the others: the mean ratio of days not covered by prescribed drugs in the post-retirement years compared to the pre-retirement years 0.58 (95% CI 0.47-0.70) in the high strain group and 0.78 (95% CI 0.71-0.87) in the low strain group (test of interaction, p= 0.0004).