Funding for this research was provided by:
Japan Dry Eye Society
Received: 17 October 2017
Accepted: 23 August 2018
First Online: 31 August 2018
Ethics approval and consent to participate
: The study protocol was approved by the Institutional Review Board of Clinical Study of Ryogoku Eye Clinic Tokyo, Japan. The study was conducted in accordance with the guidelines of the World Medical Association Declaration of Helsinki and the Ethical Guidelines for Medical and Health Research involving Human Subjects in Japan. All subjects received a full explanation of the procedures and provided their written informed consent for participation prior to inclusion in the study.
: Not applicable.
: The authors declare that they have no competing interests.
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