Optional deductibles in social health insurance systems: findings from Germany.

A fundamental aspect of the German health insurance system is the principle of solidarity. At the same time, it is possible for certain socio-economic groups to opt out of the otherwise compulsory system. To determine whether rates incorporating deductibles are compatible with the principles of solidarity and have the ability to heighten the appeal of statutory health insurance (SHI) funds compared with private health insurance companies, Germany's third largest SHI fund, Techniker Krankenkasse, implemented a pilot scheme involving the use of deductibles. Preliminary scientific evaluations of the pilot scheme indicate three main results for these deductibles: Firstly, they are compatible with the principles of solidarity in the statutory health insurance system; secondly, they provide an effective means of preventing defection to private health insurance companies and thirdly, they reduced the volume of insurance claims (moral hazard).