#1	explode "Preanesthetic‐Medication"/ all subheadings
#2	explode Premedication/ all subheadings
#3	ambulatory an?esthesia
#4	prean?est* or pre?medic*
#5	explode "Anti‐Anxiety‐Agents"/ all subheadings
#6	anxioly*
#7	#1 or #2 or #3 or #4 or #5 or #6
#8	"Surgery‐" / all SUBHEADINGS in MIME,MJME,PT
#9	explode "Ambulatory‐Surgical‐Procedures" / all subheadings
#10	explode "Specialties‐Surgical"/ all subheadings
#11	surgical (procedur* or operat*)
#12	day case or out?patient* or ambulat*
#13	#8 or #9 or #10 or #11 or #12
#14	#7 and #13
#15	RANDOMIZED‐CONTROLLED‐TRIAL in PT
#16	CONTROLLED‐CLINICAL‐TRIAL in PT
#17	RANDOMIZED‐CONTROLLED‐TRIALS
#18	RANDOM‐ALLOCATION
#19	DOUBLE‐BLIND‐METHOD
#20	SINGLE‐BLIND‐METHOD
#21	#15 or #16 or #17 or #18 or #19 or #20
#22	(TG=ANIMALS) not ((TG=HUMAN) and (TG=ANIMALS))
#23	#21 not #22
#24	CLINICAL‐TRIAL in PT
#25	explode CLINICAL‐TRIALS / all subheadings
#26	(clin* near trial*) in TI
#27	(clin* near trial*) in AB
#28	(singl* or doubl* or trebl* or tripl*) near (blind* or mask*)
#29	(#28 in TI) or (#28 in AB)
#30	PLACEBOS
#31	placebo* in TI
#32	placebo* in AB
#33	random* in TI
#34	random* in AB
#35	RESEARCH‐DESIGN
#36	#24 or #25 or #26 or #27 or #29 or #30 or #31 or #32 or #33 or #34 or #35
#37	(TG=ANIMALS) not ((TG=HUMAN) and (TG=ANIMALS))
#38	#36 not #37
#39	#38 not #23
#40	#23 or #39
#41	#14 and #40