MEDLINE (Ovid)	Embase (Ovid)	CRSO
1 exp Hearing Loss/ 2 (hearing adj2 (loss* or impair* or partial* or deficit* or deteriorat* or degenerat* or diminish* or difficult* or disabilit* or hard or one side* or unilateral)).ti,ab. 3 deaf*.ti,ab. 4 (hypoacus* or presbycus* or presbyacus* or sociocus* or nosocus* or anacus*).ti,ab. 5 Persons With Hearing Impairments/ 6 or/1‐5 7 letter/ 8 editorial/ 9 news/ 10 exp historical article/ 11 Anecdotes as Topic/ 12 comment/ 13 case report/ 14 (letter or comment*).ti. 15 or/7‐14 16 randomized controlled trial/ or random*.ti,ab. 17 15 not 16 18 animals/ not humans/ 19 Animals, Laboratory/ 20 exp animal experiment/ 21 exp animal model/ 22 exp Rodentia/ 23 (rat or rats or mouse or mice).ti. 24 or/17‐23 25 6 not 24 26 Hearing Aids/ 27 "Correction of Hearing Impairment"/is [Instrumentation] 28 (hearing adj (aid* or instrument*)).ti,ab. 29 (ear mold* or earmold* or ear mould* or earmould* or amplif*).ti,ab. 30 or/26‐29 31 (contralateral or bilateral* or binaural or unilateral* or monoaural or (bi adj3 lateral*) or (uni adj3 lateral*) or bimodal).ti,ab. 32 ((both or two or one or left or right or single or double) adj3 (side* or ear or ears or fitting*)).ti,ab. 33 31 or 32 34 30 and 33 35 ((both or two or one or left or right or single or double) adj3 (aid* or instrument*)).ti,ab. 36 34 or 35 37 25 and 36 38 randomized controlled trial.pt. 39 controlled clinical trial.pt. 40 randomized.ab. 41 placebo.ab. 42 drug therapy.fs. 43 randomly.ab. 44 trial.ab. 45 groups.ab. 46 38 or 39 or 40 or 41 or 42 or 43 or 44 or 45 47 exp animals/ not humans.sh. 48 46 not 47 49 37 and 47	1 exp *hearing impairment/ 2 (hearing adj2 (loss* or impair* or partial* or deficit* or deteriorat* or degenerat* or diminish* or difficult* or disabilit* or hard or one side* or unilateral)).ti,ab. 3 deaf*.ti,ab. 4 (hypoacus* or presbycus* or presbyacus* or sociocus* or nosocus* or anacus*).ti,ab. 5 or/1‐4 6 letter.pt. or letter/ 7 note.pt. 8 editorial.pt 9 case report/ or case study/ 10 (letter or comment*).ti. 11 or/6‐10 12 randomized controlled trial/ or random*.ti,ab. 13 11 not 12 14 animals/ not humans/ 15 nonhuman/ 16 exp animal experiment/ 17 exp Experimental Animal/ 18 animal model/ 19 exp Rodent/ 20 (rat or rats or mouse or mice).ti. 21 or/13‐20 22 5 not 21 23 Hearing Aid/ 24 (hearing adj (aid* or instrument*)).ti,ab. 25 (ear mold* or earmold* or ear mould* or earmould* or amplif*).ti,ab. 26 or/23‐25 27 (contralateral or bilateral* or binaural or unilateral* or monoaural or (bi adj3 lateral*) or (uni adj3 lateral*) or bimodal).ti,ab. 28 ((both or two or one or left or right or single or double) adj3 (side* or ear or ears or fitting*)).ti,ab. 29 27 or 28 30 26 and 29 31 ((both or two or one or left or right or single or double) adj3 (aid* or instrument*)).ti,ab. 32 30 or 31 33 22 and 32 34 random*.ti,ab. 35 factorial*.ti,ab. 36 (crossover* or cross over*).ti,ab. 37 ((doubl* or singl*) adj blind*).ti,ab. 38 (assign* or allocat* or volunteer* or placebo*).ti,ab. 39 crossover procedure/ 40 single blind procedure/ 41 randomized controlled trial/ 42 double blind procedure/ 43 or/34‐42 44 33 and 43	#1 MESH DESCRIPTOR Hearing Loss EXPLODE ALL TREES #2 ((hearing ADJ2 (loss* or impair* or partial* or deficit* or deteriorat* or degenerat* or diminish* or difficult* or disabilit* or hard or one side* or unilateral))):TI,AB,KY #3 ((hypoacus* or presbycus* or presbyacus* or sociocus* or nosocus* or anacus*)):TI,AB,KY #4 deaf*:TI,AB,KY #5 MESH DESCRIPTOR Persons With Hearing Impairments #6 #1 OR #2 OR #3 OR #4 OR #5 #7 MESH DESCRIPTOR Heating Aids #8 MESH DESCRIPTOR Correction of Hearing Impairment EXPLODE ALL TREES WITH QUALIFIERS IS #9 ((hearing next (aid* or instrument*))):TI,AB,KY #10 ((ear next mold* or earmold* or ear next mould* or earmould* or amplif*)):TI,AB,KY #11 #7 OR #8 OR #9 OR #10 #12 ((contralateral or bilateral* or binaural or unilateral* or monoaural or (bi ADJ3 lateral*) or (uni ADJ3 lateral*) or bimodal)):TI,AB,KY #13 ((both or two or one or left or right or single or double) ADJ3 (side* or ear or ears or fitting*)):TI,AB,KY #14 #12 OR #13 #15 #11 AND #14 #16 (((both or two or one or left or right or single or double) ADJ3 (aid* or instrument*))):TI,AB,KY #17 #15 OR #16 #18 #6 AND #17
CINAHL	LILACS	Trials Registries
S31 S16 AND S30 Search modes ‐ Boolean/Phrase S30 S17 or S18 or S19 or S20 or S21 or S22 or S23 or S24 or S25 or S26 or S27 or S28 or S29 S29 TX rct Search modes ‐ Boolean/Phrase S28 (MH "Placebos") Search modes ‐ Boolean/Phrase S27 (MH "Quantitative Studies") Search modes ‐ Boolean/Phrase S26 (MH "Random Assignment") Search modes ‐ Boolean/Phrase S25 (MH "Clinical Trials+") Search modes ‐ Boolean/Phrase S24 TX versus or vs Search modes ‐ Boolean/Phrase S23 TX phase AND TX ( three or III ) Search modes ‐ Boolean/Phrase S22 TX "control group" Search modes ‐ Boolean/Phrase S21 TX "treatment arm" Search modes ‐ Boolean/Phrase S20 TX ( blind* or mask* ) AND TX ( single or double or triple or treble ) Search modes ‐ Boolean/Phrase S19 TX trial AND TX ( control* or comparative ) Search modes ‐ Boolean/Phrase S18 TX "cross over" Search modes ‐ Boolean/Phrase S17 TX random* or factorial* or placebo* or assign* or allocat* or cossover* Search modes ‐ Boolean/Phrase S16 S5 AND S15 Search modes ‐ Boolean/Phrase S15 S13 OR S14 Search modes ‐ Boolean/Phrase S14 TX ((both or two or one or left or right or single or double) N3 (aid* or instrument*)) Search modes ‐ Boolean/Phrase S13 S9 AND S12 Search modes ‐ Boolean/Phrase S12 S10 OR S11 Search modes ‐ Boolean/Phrase S11 TX ((both or two or one or left or right or single or double) N3 (side* or ear or ears or fitting*)) Search modes ‐ Boolean/Phrase S10 TX (contralateral or bilateral* or binaural or unilateral* or monoaural or (bi N3 lateral*) or (uni N3 lateral*) or bimodal) Search modes ‐ Boolean/Phrase S9 S6 OR S7 OR S8 Search modes ‐ Boolean/Phrase S8 TX (ear N3 mold*) or earmold* or (ear N3 mould*) or earmould* or amplif* Search modes ‐ Boolean/Phrase S7 TX (hearing N3 (aid* or instrument*) Search modes ‐ Boolean/Phrase S6 (MH "Hearing Aids") Search modes ‐ Boolean/Phrase S5 S1 OR S2 OR S3 OR S4 Search modes ‐ Boolean/Phrase S4 TX hypoacus* or presbycus* or presbyacus* or sociocus* or nosocus* or anacus* Search modes ‐ Boolean/Phrase S3 TX deaf* Search modes ‐ Boolean/Phrase S2 TX (hearing N2 (loss* or impair* or partial* or deficit* or deteriorat* or degenerat* or diminish* or difficult* or disabilit* or hard or one side* or unilateral)) Search modes ‐ Boolean/Phrase S1 (MH "Hearing Disorders") OR (MH "Deafness") OR (MH "Hearing Loss, Partial+") OR (MH "Hyperacusis") Search modes ‐ Boolean/Phrase	Controlled Clinical Trials: TW:"hearing aid" OR TW:"hearing aids" OR TW:Audífonos OR TW:"Auxiliares de Audição"	ClinicalTrials.gov ("hearing aid" OR "hearing aids") AND randomized ICTRP Title: hearing aids OR "hearing aid"