Who bears the burden of social insurance?

"Using the society-managed health insurance data, which is cross-sectional time-series and covers 1,670 health insurance societies for seven years (FY1995-2001), we found for the first time in Japan that the majority of the employer's contribution to health insurance is shifting back onto the employees in the form of wage reduction. On the other hand, we cannot find such evidence for the contribution to long-term care insurance using a two-year (FY2000-01) panel data set"--National Bureau of Economic Research web site.