Table 1.

List of Papers Reviewed With Information About Research Design and Outcome Measures.

	Design	Control group and training	Quality of randomization	Outcome measures
Smith et al. (2017) Adult CI users, N = 21 Self-administered melody training 3.5 hours/week for 4 weeks	No control	NA	NA	Three music assessments: music enjoyment, pitch and timbre discrimination, and complex melody and patterns Sentences in noise and quiet
Hutter et al. (2015) Newly implanted CI adults, N = 12 Music therapy (10 45-minute sessions)	No control	NA	NA	3 questionnaires are sound quality, self-concept, and satisfaction Music (pitch timbre, melody)
Cheng et al. (2018) CI children, N = 22 MCI training (30–60 hours over 8 weeks)	No control	NA	NA	MCI Lexical tones Sentences in quiet
Firestone et al. (2020) CI adults, N = 11 Active music listening 40 mins/day for 4 or 8 weeks	No control	NA	NA	Speech perception (words, sentences in quiet and noise) Hearing questionnaire EEG (acoustic change response)
Lo et al. (2015) CI adults, N = 8 in each group 2 music trainings 1–2 hours/week for 6 weeks	RCT	MCI interval training MCI duration training (No non-music control)	Subjects were randomized between the two music training groups only	MCI Speech perception in noise Consonant discrimination in quiet and in noise Prosody (question/statement)
Yucel et al. (2009) 18 newly implanted child CI users, N = 9 each group 2 years home training on computer/keyboard	CT	No-training control	No randomization (Self-selected test group)	Closed-set word identification and two open-set sentence identification tests Music questionnaires
Lo et al. (2020) 9 hearing-impaired children with hearing aids or CIs 12 weeks of weekly 40-minute group music therapy, plus online exercises	CT	No-training control A subgroup waited 12 weeks before starting training	Pseudorandom allocation: Parents could opt for a different group for convenience	Sentences in noise Pitch Timbre Modulation detection Emotional prosody Question/statement prosody
Petersen et al. (2012) 18 newly implanted CI adults, N = 9 in each group 1 hour/week for 6 months face-to-face training (singing, playing, listening) plus home practice using computer apps	CT	No-training control	No randomization: groups matched on hearing factors.	Music tests (5 subtests) Sentences in noise Emotional prosody
Dubinsky et al. (2019) Older adults with normal to mild hearing impairment, N = 45 (test), 30 (control) Group 2-hour/week singing course plus 1-hour/week online musical and vocal training exercises for 10 weeks	CT	No-training control	No randomization: self-selected music group with 9 withdrawals	Sentences in noise Frequency difference limens Frequency following response (EEG)
Chari et al. (2020) Adult CI users, N= 7 in two music training groups 1 month of auditory-only MCI 1 month of auditory-motor MCI N = 4 in no-training control	RCT	No-training control	Randomized: but some withdrew and very small groups	Consonant perception, sentences in noise Speech prosody Pitch perception
Fuller et al. (2018) Adult CI users, N = 6, 7, 6 Two types of music training: MCI training Music therapy Six 2-hour weekly sessions	RCT	Group therapy consisting of writing, cooking, and woodworking	Randomized: but very small groups and did not say how randomized	Speech understanding in quiet and noise Vocal emotion identification MCI Quality of life
Good et al. (2017) Child CI users 6 months piano lessons N = 9 in active control and test groups	RCT	Art classes	Partial randomization: also 7/25 withdrew	Music ability Emotional speech prosody
Bedoin et al. (2018) Child CI users, N = 10 Music (rhythmic) primes vs. non-music primed in syntax training Eight 20-minute sessions over 4 weeks	Crossover	Nonmusical auditory primes	NA	Syntactic judgment Grammatical processing

Note. (R)CT = (randomized) controlled trial; MCI = melodic contour identification; CI = cochlear implant.