136
Participants
Start Date
December 13, 2019
Primary Completion Date
December 21, 2019
Study Completion Date
December 31, 2049
Presbyopic Glasses/ Intervention Group
Immediate provision of a free pair of spherical presbyopic glasses to correct the worker's vision for optimal picking distance, astigmatism is corrected.
Gaoming, Foshan, Guangdong, Foshan
Zhongshan Ophthalmic Center, Sun Yat-sen University
OTHER