Table 2 Quality assessment using a version of the Newcastle-Ottawa modified for cross-sectional studies

Cockerill, CC (2016) [25]

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^*

^*

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Palmer, E (2014) [27]

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^*

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^******

Xue, X-C (2014) [26]

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^*

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^*****

Sun, YF (2012) [abstract] [article in Chinese] [14]

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^*

^*****

Duray, A (2011) [19]

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^*

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Baloglu, H (2010) [17]

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^*

^****

Soldatskiĭ, IuA (2009) [abstract] [article in Russian] [13]

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^*

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Mammas, IN (2006) [20]

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^******

Sisk, J (2006)[18]

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^******

Ribeiro, KM (2006)[37]

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^*

^****

Chen, R (2005)[21]

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^*

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