7. QUIPS Risk of bias domain summary by study.

Study	Year	Study Participation	Study Attrition	Prognostic Factor Measurement	Outcome Measurement	Study Confounding	Statistical Analysis and Reporting
Beneciuk 2017	2017	Moderate	Moderate	Moderate	Low	High	Low
Besen 2015	2015	Moderate	Moderate	Low	Low	Low	Low
Bishop 2015	2015	High	Moderate	Low	Low	Low	Low
Butler 2007	2007	Moderate	Moderate	Moderate	Low	Low	Low
Carriere 2015	2015	Low	Moderate	Moderate	Moderate	Low	Low
Casey 2008	2008	Moderate	Moderate	Low	Low	Moderate	Low
Demmelmaier 2010	2010	High	High	High	Low	Moderate	Moderate
Dionne 1997	1997	Moderate	Low	Moderate	Low	High	Low
Downie 2016	2016	Moderate	Low	Low	Moderate	Low	Low
Du Bois 2008	2008	Moderate	Low	Moderate	Low	Moderate	Moderate
Enthoven 2006	2006	Low	Low	Moderate	Low	Low	Low
Enthoven 2016	2016	Moderate	Low	Low	Low	High	Moderate
Foster 2008	2008	Moderate	High	Low	Low	Low	Low
George 2010	2010	Low	Low	Moderate	Low	High	Low
Gervais 1991	1991	Low	Low	Low	Low	Moderate	Low
Glattacker 2013	2013	Moderate	Moderate	Low	Low	Low	Low
Goldstein 2002	2002	Moderate	Low	Low	Low	Moderate	Low
Gross 2010	2010	Moderate	Low	Low	Low	Low	Low
Grotle 2006	2006	High	Moderate	Moderate	Low	Moderate	Low
Haas 2014	2014	High	Low	Low	Low	Moderate	Low
Hagen 2005	2005	Moderate	Low	Moderate	Low	Low	Low
Haldorsen 1998	1998	Moderate	Low	High	Low	High	Moderate
Harkapaa 1996	1996	High	Moderate	Low	Low	Low	Low
Hazard 1996	1996	Moderate	Low	Low	Low	Moderate	Moderate
Henschke 2008	2008	Low	Low	Low	Low	Low	Low
Heymans 2006	2009	Moderate	Low	Low	Low	Low	Low
Hildebrandt 1997	1997	High	Moderate	Moderate	Low	High	Moderate
Jellema 2002	2002	High	Moderate	Low	Low	High	High
Jensen 2000	2000	Moderate	Moderate	Moderate	Low	Moderate	Low
Jensen 2013	2013	Moderate	Low	Moderate	Low	Moderate	Low
Karjalainen 2003	2003	Moderate	Low	Low	Low	Low	Moderate
Kongsted 2014	2014	Low	Moderate	Low	Low	Low	Low
Leboeuf‐Yde 2004	2004	Moderate	Moderate	Moderate	Low	Moderate	Moderate
Lindell 2010	2010	Low	Low	Moderate	Low	Low	Low
Macedo 2014	2014	Moderate	Low	Moderate	Low	High	Low
Magnussen 2007	2007	Moderate	Moderate	Moderate	Moderate	High	Low
Michaelson 2004	2004	Low	Low	Low	Low	Moderate	Moderate
Morlock 2002	2002	Moderate	High	Low	Low	Low	Moderate
Myers 2007	2007	Low	Low	Low	Low	Low	Low
Niemisto 2004	2004	Low	Low	Moderate	Low	Low	Moderate
Opsahl 2016	2016	Low	Low	Moderate	Moderate	Low	Low
Opsommer 2017	2017	Low	Moderate	Low	Moderate	High	Low
Petersen 2007	2007	Low	Low	Moderate	Low	Moderate	Low
Rasmussen‐Barr 2012	2012	Low	Moderate	Moderate	Low	High	Low
Reeser 2001	2001	Moderate	High	Low	Low	High	Moderate
Reiso 2003	2003	Moderate	Low	Moderate	Low	Low	Moderate
Reme 2009	2009	Low	Low	Moderate	Low	Low	Moderate
Rundell 2017	2017	Moderate	Moderate	Low	Low	Moderate	Low
Sandstrom 1986	1986	Moderate	Low	Moderate	Low	High	Moderate
Schultz 2004	2004	High	Low	Low	Low	Moderate	Moderate
Shaw 2009	2009	High	Moderate	Moderate	Moderate	Low	Low
Sherman 2009	2009	Moderate	Low	Moderate	Low	Low	Low
Steenstra 2005	2005	Low	Low	Moderate	Low	Moderate	Low
Tran 2015	2015	Moderate	Low	Moderate	Low	Moderate	Moderate
Truchon 2012	2012	Moderate	Low	High	Low	Low	Low
Turner 2008	2008	Moderate	Low	Moderate	Low	Low	Low
Underwood 2007	2007	Low	Moderate	Moderate	Low	Low	Low
Van Hooff 2014	2014	Low	Low	Low	Low	Moderate	Moderate
Van Wijk 2008	2008	Moderate	Low	High	Low	Low	Low
Yelland 2006	2006	Moderate	Low	Low	Low	Moderate	Low