Study design setting, and participants
This study is a retrospective analysis of payment data publicly disclosed by major pharmaceutical companies in Japan. The analysis included all neurologists certified by the Japanese Society of Neurology (JSN) as of February 2022. The JSN, established in 1960, is the preeminent professional medical society for neurologists and is the sole credentialing body for neurologists in Japan since 1967. As of the specified date, 6107 neurologists were recognized as board-certified by the JSN[50].