Ohtori S, Yamashita , Murata Y, Eguchi Y, Aoki Y, Ataka H, Hirayama J, Ozawa T, Morinaga T, Arai H, Mimura M, Kamoda H, Orita S, Miyagi M, Miyashita , Okamoto Y, Ishikawa T, Sameda H, Kinoshita , Hanaoka E, Suzuki M, Suzuki M, Aihara T, Ito T, Inoue G, Yamagata M, Toyone T, Kubota G, Sakuma Y, Oikawa Y, Inage K, Sainoh T, Yamauchi K, Takahashi , Chiba Low Back Pain Research Group