論文（英文）
Risk-adjusted analyses of the effects of hospital and surgeon volumes on postoperative complications and the modified Rankin scale after clipping of unruptured intracranial aneurysms in Japan.
Yasunaga H, Matsuyama Y, Ohe K for the Japan Neurosurgical Society. Risk-adjusted analyses of the effects of hospital and surgeon volumes on postoperative complications and the modified Rankin scale after clipping of unruptured intracranial aneurysms in Japan. Neurologia Medico-Chirurgica 2008; 48: 531-538.