Funding for this research was provided by:
Allergan AG, Zurich
Text and Data Mining valid from 2019-02-01
Received: 17 May 2018
Accepted: 5 January 2019
First Online: 1 February 2019
Compliance with ethical standards
: Study design was approved by Ethics Commission of Zurich (KEK-ZH StV 16/2005). All patients provided written consent to participate.
: The datasets used and/or analyzed during this current study are available from the corresponding author on reasonable request.
: The authors declare that they have no competing interests.
: The drug botulinum toxin type A was provided free of charge by Allergan AG, Zurich, Switzerland. The role of Allergan AG was solely in provision of the medication. The company was not involved in the study design; data collection, analysis, or interpretation; writing of the report; or decision to submit the paper for publication.