Table 2. Quality Assessment.

Study/Quality Scale	Q1	Q2	Q3	Q4	Q5	Q6	Q7	Q8	Overall Rating
Antoniou, 2000	I	I	II	II	II	II	II	I	***
Asch, 2002	II	II	II	III	II	II	I	III	**
Atlas, 2009	III	II	II	II	II	II	II	III	**
Balyk, 2008	II	II	I	II	II	I	III	II	***
Barrett, 2001	II	II	II	III	III	II	II	I	**
Buckley, 2002	III	II	II	III	III	II	II	II	**
Deustsch, 2006	II	II	II	IIII	III	III	III	III	*
Glowacki, 1997	III	II	II	IIII	III	IIII	III	II	*
Greenough, 1994	II	II	II	III	II	III	II	II	**
Henn III, 2008	III	II	II	I	I	II	II	II	***
Johannsen, 1997	II	II	II	II	III	II	II	II	**
Lin, 2000	II	II	II	III	III	III	II	II	*
MacKay, 1995	II	II	II	III	III	IIII	III	III	*
McKee, 2000	II	II	II	II	III	II	III	II	**
Nagle, 1994	II	II	II	III	IIII	III	III	II	*
Nicholson, 2003	II	II	II	II	II	II	II	I	***
Rosenberger, 2008	I	II	II	III	II	II	II	I	***
Spangehl, 2002	I	II	II	II	II	I	III	II	***
Straub, 1999	III	II	II	IIII	III	III	II	IIII	*
Westkaemper, 1998	II	II	I	IIII	II	II	II	II	**