<p>Additional file 3. Item by item results using the AMSTAR assessment instrument. S c i e n Reference L ti i fi s c D t q M u u e p o a t li f C li h c h t o C a i a y d o C t n r o s m S o e c a f f A p t S n s l c s o P r a c f t u t t r u p e t i l u d e u c b r h u e i d e r d o li i e s n c T y d i i m c o n o ti t o s / s e b a r s f fi t e ti s i ti i i p c o a l e c u n o d v u q f l e x s s i n e e b u s c c o e n b s li li a i c ti l f d g i i t c li n o o u s a s a g e a t t r n d t p t s n r ti y e e a e u p u a p a o a r n d d r d s r t n s e ( d i o i s o u a s s % d s e p e e v r v e t ) a t s r s s i e o s a t u p i a s d s i s s a d r a p e e e d e t e i o t p d d a e d a x e v e r ? ? r d ? t t s i l o c ? e r d y p h d a p e i r ? c r d n i ti o ? c a o v o t n i n e ? d c ? e l d u ? s i o n s ? Brown et al.[10] yes ca yes ca no yes yes yes yes yes no 78 Carayol et al.[11] yes ca ca ca no yes yes yes yes yes no 75 Carayol et al.[12] yes ca yes ca no yes yes yes yes yes no 78 Cramer et al.[13] yes yes yes ca no yes yes yes yes na no 78 Duijts et al.[16] yes ca no ca no yes no no yes yes no 44 Fong et al.[17] yes yes yes ca no yes yes yes yes yes no 80 Jacobsen et al.[18] yes ca no no no yes yes yes ca no no 44 Kangas et al.[19] yes yes no no no yes yes yes yes yes no 64 Meneses-Echavez et al.[24] yes yes ca yes no yes yes yes yes yes no 80 Meneses-Echavez et al.[25] yes yes ca yes no yes yes yes yes yes no 80 Meneses-Echavez et al.[26] yes ca yes yes no yes yes yes yes no no 70 Tian et al.[31] yes ca no ca no yes yes yes yes no no 56 Van Haren et al.[33] yes no yes no no yes yes yes yes yes no 64 Van Vulpen et al.[34] yes yes ca ca no yes yes yes yes yes no 78 Velthuis et al.[35] yes yes ca ca no yes yes yes yes no no 67 Zou et al.[36] yes ca ca no no yes yes yes yes yes no 67 Notes: ca, can’t answer; na, not applicable; Possible responses were “Yes”, “No”, “Can’t Answer”, “Not </p><p>Applicable”. “Can’t Answer” chosen when item is relevant but not described; “Not Applicable” chosen when item is not relevant (for example, insufficient number of studies to assess publication bias);a,scores adjusted for “can’t answer’ and “not applicable” responses.</p>