At the same time, the use of a personal identifier for data linkage is reportedly complicated due to privacy legislation in Australia, the Czech Republic, Israel, Italy, Japan, Korea and Norway. By contrast, the United Kingdom, Sweden, Portugal and Denmark strengthened their legislative framework to permit privacy-protective data use. In the United Kingdom notably, several legislative framew'orks w'ere introduced so that information can be collected, held securely and made available with safeguards in place to protect individuals’ data.