Search strategy for Ovid EMBASE 1974 to 2013 January 18
1	randomized‐controlled‐trial/ or randomization/ or controlled‐study/ or multicenter‐study/ or phase‐3‐clinical‐trial/ or phase‐4‐clinical‐trial/ or double‐blind‐procedure/ or single‐blind‐procedure/
2	(random* or cross?over* or multicenter* or factorial* or placebo* or volunteer*).mp. [mp=title, abstract, subject headings, heading word, drug trade name, original title, device manufacturer, drug manufacturer, device trade name, keyword]
3	((singl* or doubl* or trebl* or tripl*) adj3 (blind* or mask*)).ti,ab.
4	(latin adj square).mp.
5	(animals not (humans and animals)).sh.
6	or/1‐4
7	6 not 5
8	(gastric adj3 band*).mp.
9	exp overweight/ or exp obesity/
10	exp gastroplasty/ or exp bariatric surgery/
11	(obes* or overweight* or bariatric or BMI or body mass index).mp.
12	or/8‐11
13	exp fiber optics/
14	(fibreoptic or fiberoptic or fiberscope or fibrescope).mp.
15	exp fiberoptic bronchoscopy/ or exp fiberoptic laryngoscope/
16	((fibre or fiber) adj3 (optic or scope$)).mp.
17	exp respiratory tract intubation/
18	(intub$ or ((airway or respiratory tract) adj3 manage$)).mp.
19	17 or 18
20	or/13‐16
21	exp bronchoscopes/ or exp laryngoscopes/
22	(bronchoscop* or laryngoscop*).mp.
23	(21 or 22) and flexible.ti,ab.
24	exp flexible bronchoscope/
25	(flex$ adj3 scop$).mp.
26	(Ambu adj3 (Ascope or scop$)).mp.
27	or/23‐26
28	20 or 27
29	7 and 12 and 28 and 19