Table 1 Risk of Bias Newcastle-Ottawa Scale (NOS) of uncontrolled studies (n=12)

Alexaitis et al. 2014 [27]

★★★★

-

-

Poor

Amato et al. 2006 [28]

-

-

★

Poor

Andersen et al. 2017 [29]

★★

-

★

Poor

Davis et al. 2008 [30]

★★★

-

★

Poor

Eskandaria et al. 2018 [31]

★★

★

-

Poor

Hevener et al. 2016 [32]

-

-

-

Poor

Link et al. 2016 [33]

★★★★

-

-

Poor

McCue et al. 2004 [34]

★

-

★★

Poor

Mitchell et al. 2018 [9]

-

-

★★

Poor

Sinitsky et al. 2017 [35]

★

-

★

Poor

Thakker et al. 2018 [36]

★★★

-

★

Poor

Weddle et al. 2016 [37]

★★

-

★★★

Poor