Table 1. Methodological quality of the included studies based on the STROBE criteria.

Reference	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15
Total score	9	10	9.5	10.5	8.5	7.5	10	9	6.5	10.5	7	9.5	10	9.5	9
Reference	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Total score	8	10	10	7	10	9	5.5	10	10	9.5	9.5	10	8	10	9
Reference	31	32	33	34	35	36	37	38	39	40	41	42	43	44	45
Total score	9	9	8	9	8.5	6.5	10	9.5	7	6	8	7.5	9	9.5	9
Methodological quality was assessed using a checklist based on the STROBE criteria, consisting of 11 items. Items were scored as following: 1 = described, ½ = partly described, 0 = not/insufficiently described. Total score ranged from 0-11, where scores between 0 - 6 reflected poor study quality, >6 - <8 moderate study quality, ≥8 - <10 good study quality and ≥10 excellent study quality. 1. Amsterdam et al. 2009, 2. Banihashemi et al. 2009, 3. Bhatt et al. 2004, 4. Chandra et al. 2009, 5. Cheng et al. 2010, 6. Diercks et al. 2006, 7. Diercks et al. 2007, 8. Dziewierz et al. 2007, 9. Ellis et al. 2004, 10. Engel et al. 2015, 11. Ferreira et al. 2004, 12. Goldberg et al. 2007, 13. Hoekstra et al. 2005, 14. Kassab et al. 2013, 15. Kassaian et al. 2015, 16. Lee et al. 2008, 17. Maddox et al. 2012, 18. Maier et al. 2008, 19. Mandelzweig et al. 2006, 20. Mehta et al. 2006, 21. Miller et al. 2007, 22. Nieuwlaat et al. 2004, 23. Olivari et al. 2012, 24. Peterson et al. 2003, 25. Peterson et al. 2006, 26. Peterson et al. 2008, 27. Polonski et al. 2007, 28. Rao et al. 2009, 29. Roe, Parsons, et al. 2005, 30. Roe, Peterson, et al. 2005, 31. Roe, Chen, et al. 2006, 32. Roe, Peterson, et al. 2006, 33. Roe et al. 2007, 34. Schiele et al. 2005, 35. Sherwood et al. 2014, 36. Sinon et al. 2014, 37. Somma et al. 2012, 38. Sonel et al. 2005, 39. Tang et al. 2005, 40. Tricoci et al. 2006, 41. Valli et al. 2014, 42. Vikman et al. 2003, 43. Yan et al. 2007, 44. Zeymer et al. 2014, 45. Zhang et al. 2009.