Screening
Identification of studies via other methods
Identification of studies via databases and registers
Reports sought for retrieval (n = 0)
Records excluded after reading the title and abstract (n = 522)
Reports excluded (n = 0)
Reports assessed for eligibility(n = 0 )
Identifacation
Records identified from: Citation searching (n = 0)
Records identified through database searching(n=1045)PubMed (n = 180)Embase (n = 220)Cochrane (n = 39)Web of science (n = 481)CNKI (n = 16)Wanfang (n = 47)VIP (n = 23)CBM (n = 39)
Records removed before screening:Duplicate records removed (n = 436)
Reports not retrieved(n = 0)
Reports assessed for eligibility (n = 36)
Full-text articles evaluated for eligibility (n = 87)Exclude records (n = 51)-Study design or study content is not in compliance (n = 16)-Non-original research (n = 3)-Diagnostic criteria for BPD did not meet inclusion criteria (n = 11)-The definition of BPD is not provided (n = 2)-Incomplete data (n = 6)-Overlapping data (n = 3)-Unable to access full text (n = 9)-Inclusion of populations not meeting criteria (n = 1)
Included
Records after the removal of duplicates (n = 609)
Full-text articles evaluated for eligibility (n = 87)
Studies included in quantitativesythesis(Meta-analysis)(n = 36)
