Excessive psychological stress preceding the onset of idiopathic cervical dystonia.

"Declarations Conflict of interestDirk Dressler: received honoraria for services provided to Allergan, Ipsen, Merz, Lanzhou Institute of Biological Products, Medy-Tox, Revance, Desitin, Syntaxin, AbbVie, Medtronic, St Jude, Boston Scientific, Almirall, Bayer, Sun, Teva, UCB, and IAB-Interdisciplinary Working Group for Movement Disorders. He is shareholder of Allergan and holds patents on botulinum toxin and botulinum toxin therapy. Bruno Kopp and Lizhen Pan: have nothing to declare. Fereshte Adib Saberi: is founder and owner of IAB—Interdisciplinary Working Group for Movement Disorders. She received reimbursement from Abbot, AbbVie, Almirall, Allergan, Bayer, Desitin, Dynamed, Hempel GesundheitsPartner, Ipsen, Johnson & Johnson, Licher, Meda, Medtronic, Merz, Orion, PTZ Nawrath, Sensomotorik & Rehabilitation Hellmuth & Thiel, Sintetica, Sporlastic, Sun, Teva, Tricumed, TRS Med, and UCB. Conflict of interest Dirk Dressler: received honoraria for services provided to Allergan, Ipsen, Merz, Lanzhou Institute of Biological Products, Medy-Tox, Revance, Desitin, Syntaxin, AbbVie, Medtronic, St Jude, Boston Scientific, Almirall, Bayer, Sun, Teva, UCB, and IAB-Interdisciplinary Working Group for Movement Disorders. He is shareholder of Allergan and holds patents on botulinum toxin and botulinum toxin therapy. Bruno Kopp and Lizhen Pan: have nothing to declare. Fereshte Adib Saberi: is founder and owner of IAB—Interdisciplinary Working Group for Movement Disorders. She received reimbursement from Abbot, AbbVie, Almirall, Allergan, Bayer, Desitin, Dynamed, Hempel GesundheitsPartner, Ipsen, Johnson & Johnson, Licher, Meda, Medtronic, Merz, Orion, PTZ Nawrath, Sensomotorik & Rehabilitation Hellmuth & Thiel, Sintetica, Sporlastic, Sun, Teva, Tricumed, TRS Med, and UCB."

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