834
Participants
Start Date
September 1, 2013
Primary Completion Date
November 30, 2015
Study Completion Date
November 30, 2016
Mental Development Index;Auditory Brainstem Response;okineticnystagmus
mental development index(MDI)\<70:cognitive delay do not pass auditory brainstem response(ABR):hearing impairment do not pass okineticnystagmus:visual impairment Patent Ductus Arteriosus
yangjie
OTHER