Appendix 1. MEDLINE search strategy

1. RANDOMIZED CONTROLLED TRIAL.pt.
2. CONTROLLED CLINICAL TRIAL.pt.
3. RANDOMIZED CONTROLLED TRIALS.sh.
4. RANDOM ALLOCATION.sh.
5. DOUBLE BLIND METHOD.sh.
6. SINGLE BLIND METHOD.sh.
7. 1 or 2 or 3 or 4 or 5 or 6
8. (ANIMALS not HUMAN).sh.
9. 7 not 8
10. CLINICAL TRIAL.pt.
11. exp CLINICAL TRIALS/
12. (clin$ adj25 trial$).ti,ab.
13. ((singl$ or doubl$ or trebl$ or tripl$) adj25 (blind$ or mask$)).ti,ab.
14. PLACEBOS.sh.
15. placebo$.ti,ab.
16. random$.ti,ab.
17. RESEARCH DESIGN.sh.
18. 10 or 11 or 12 or 13 or 14 or 15 or 16 or 17
19. 18 not 8
20. 19 not 9
21. COMPARATIVE STUDY.sh.
22. exp EVALUATION STUDIES/
23. FOLLOW UP STUDIES.sh.
24. PROSPECTIVE STUDIES.sh.
25. (control$ or prospectiv$ or volunteer$).ti,ab.
26. 21 or 22 or 23 or 24 or 25
27. 26 not 8
28. 27 not (9 or 20)
29. 9 or 20 or 28
30. nause$.mp.
31. vomit$.mp.
32. emesis.mp.
33. emet$.mp.
34. anti‐eme$.mp.
35. antieme$.mp.
36. antiemetics.sh.
37. nausea.sh.
38. vomiting.sh.
39. 30 or 31 or 32 or 33 or 34 or 35 or 36 or 37 or 38
40. droperidol.mp.
41. droleptan$.mp.
42. dehydrobenzperidol$.mp.
43. droperdal$.mp.
44. inapsine$.mp.
45. droperol$.mp.
46. sintodian$.mp.
47. dridol$.mp.
48. inapsin$.mp.
49. paxical$.mp.
50. dehidrobenzperidol$.mp.
51. 40 or 41 or 42 or 43 or 44 or 45 or 46 or 47 or 48 or 49 or 50
52. butyrophenone$.mp.
53. exp butyrophenones/
54. 52 or 53
55. 51 or 54
56. 29 and 39 and 55