Correlation between growth differentiation factor 5 (rs143383) gene polymorphism and knee osteoarthritis: an updated systematic review and meta-analysis

Table 2 Quality assessment of case-control studies

Author, Year	Is the case definition adequate?	Representativeness of the cases	Selection of controls	Definition of controls	Comparability of cases and controls on the basis of the design or analysis	Ascertainment of exposure	Same method of ascertainment for cases and controls	Non-response rate	NOS
Miyamoto, 2007 (1) [14]	⭐	⭐	⭐	⭐	NA	⭐	⭐	NA	6
Miyamoto, 2007 (2) [14]	⭐	⭐	⭐	⭐	NA	⭐	⭐	NA	6
Tsezou, 2008 [20]	⭐	⭐	⭐	⭐	⭐	⭐	⭐	NA	7
Yao, 2008 [23]	⭐	⭐	⭐	⭐	⭐⭐	⭐	⭐	NA	8
Vaes, 2009 [21]	⭐	⭐	⭐	⭐	⭐⭐	⭐	⭐	NA	8
Valdes, 2009 [22]	⭐	⭐	⭐	⭐	⭐	⭐	⭐	NA	7
Takahashi, 2010 [18]	⭐	⭐	⭐	⭐	⭐	⭐	⭐	NA	7
Cao, 2010 [11]	NA	⭐	⭐	⭐	⭐⭐	⭐	⭐	Na	7
Tawonsawatruk, 2011 [19]	⭐	⭐	⭐	⭐	⭐⭐	⭐	⭐	NA	8
Shin, 2012 [17]	⭐	⭐	⭐	⭐	⭐⭐	⭐	⭐	NA	8
Mishra, 2017 [13]	⭐	⭐	⭐	⭐	⭐⭐	⭐	⭐	NA	8
Ozcan, 2017 [16]	⭐	⭐	⭐	⭐	⭐	⭐	⭐	NA	7
Elazeem, 2017 [12]	⭐	⭐	⭐	⭐	⭐⭐	⭐	⭐	NA	8
Zhang, 2019 [24]	NA	⭐	⭐	⭐	⭐⭐	⭐	⭐	NA	7
Mohasseb, 2019 [15]	⭐	⭐	⭐	⭐	⭐⭐	⭐	⭐	NA	8

ISSN: 1749-799X