CENTRAL (CRS)	MEDLINE (Ovid)	Embase (Ovid)
1 MESH DESCRIPTOR Otitis Media with Effusion EXPLODE ALL AND CENTRAL:TARGET 39 2 ("otitis media" adj6 effusion):AB,EH,KW,KY,MC,MH,TI,TO  AND CENTRAL:TARGET 730 3 (OME):TI,TO  AND CENTRAL:TARGET 0 4 (Secretory otitis media):AB,EH,KW,KY,MC,MH,TI,TO  AND CENTRAL:TARGET 264 5 (Serous otitis media):AB,EH,KW,KY,MC,MH,TI,TO  AND CENTRAL:TARGET 49 6 (Middle‐ear effusion):AB,EH,KW,KY,MC,MH,TI,TO  AND CENTRAL:TARGET 238 7 (glue ear):AB,EH,KW,KY,MC,MH,TI,TO  AND CENTRAL:TARGET 62 8 (middle‐ear perfusion):AB,EH,KW,KY,MC,MH,TI,TO  AND CENTRAL:TARGET 1 9 MESH DESCRIPTOR Otitis Media AND CENTRAL:TARGET 784 10 (otitis media):TI,TO  AND CENTRAL:TARGET 1653 11 #9 OR #10 AND CENTRAL:TARGET 1911 12 (((effusion or Recurrent or persistent or serous or secretory or perfusion) adj3 otitis)):AB,EH,KW,KY,MC,MH,TI,TO  AND CENTRAL:TARGET 1010 13 #11 AND #12 AND CENTRAL:TARGET 766 14 #1 OR #2 OR #3 OR #4 OR #5 OR #6 OR #7 OR #8 OR #13 AND CENTRAL:TARGET 1066	MEDLINE (Ovid MEDLINE® Epub Ahead of Print, In‐Process & Other Non‐Indexed Citations, Ovid MEDLINE® Daily and Ovid MEDLINE®) 1946 to present 1 exp Otitis Media with Effusion/ 5807 2 ("otitis media" adj6 effusion).ab,ti. 3451 3 OME.ti. 469 4 Secretory otitis media.ab,ti. 953 5 Serous otitis media.ab,ti. 567 6 Middle‐ear effusion.ab,ti. 1444 7 Glue ear.ab,ti. 303 8 middle‐ear perfusion.ab,ti. 3 9 Otitis Media/ 17663 10 "otitis media".ti. 11554 11 9 or 10 21726 12 ((effusion or Recurrent or persistent or serous or secretory or perfusion) adj3 otitis).ab,ti. 6178 13 11 and 12 4299 14 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8 or 13 8976 15 randomized controlled trial.pt. 542809 16 controlled clinical trial.pt. 94373 17 randomized.ab. 533045 18 placebo.ab. 221237 19 drug therapy.fs. 2370147 20 randomly.ab. 365421 21 trial.ab. 567106 22 groups.ab. 2243598 23 15 or 16 or 17 or 18 or 19 or 20 or 21 or 22 5110951 24 exp animals/ not humans.sh. 4882975 25 23 not 24 4445451 26 14 and 25 2367	Embase 1974 to present 1 exp secretory otitis media/ 5885 2 ("otitis media" adj6 effusion).ab,ti. 3999 3 OME.ti. 540 4 Secretory otitis media.ab,ti. 1051 5 Serous otitis media.ab,ti. 615 6 Middle‐ear effusion.ab,ti. 1627 7 glue ear.ab,ti. 351 8 middle‐ear perfusion.ab,ti. 3 9 otitis media/ 21684 10 otitis media.ti. 12337 11 9 or 10 27117 12 ((effusion or Recurrent or persistent or serous or secretory or perfusion) adj3 otitis).ab,ti. 7383 13 11 and 12 5219 14 1 or 2 or 4 or 5 or 6 or 7 or 8 or 13 9824 15 (random* or factorial* or placebo* or assign* or allocat* or crossover*).tw. 2194998 16 (control* adj group*).tw. 724788 17 (trial* and (control* or comparative)).tw. 701811 18 ((blind* or mask*) and (single or double or triple or treble)).tw. 288542 19 (treatment adj arm*).tw. 22835 20 (control* adj group*).tw. 724788 21 (phase adj (III or three)).tw. 67227 22 (versus or vs).tw. 2371156 23 rct.tw. 43341 24 crossover procedure/ 68008 25 double blind procedure/ 187232 26 single blind procedure/ 43636 27 randomization/ 91740 28 placebo/ 370427 29 exp clinical trial/ 1625769 30 parallel design/ 14463 31 Latin square design/ 394 32 15 or 16 or 17 or 18 or 19 or 20 or 21 or 22 or 23 or 24 or 25 or 26 or 27 or 28 or 29 or 30 or 31 5531900 33 exp ANIMAL/ or exp NONHUMAN/ or exp ANIMAL EXPERIMENT/ or exp ANIMAL MODEL/ 29428557 34 exp human/ 22679343 35 33 not 34 6749214 36 32 not 35 4834087 37 14 and 36 1820