Table 2.

General characteristics of RCT studies included.

Study	Region	Final Sample Size (MI/CG)	Population characteristics	Music types	MI duration and frequency	HRV measurement tools	HRV parameters
Chang et al. (2011)	China	27/27	Cardiac catheterization patients	Sedative music	30 min		LF/HF
Du et al. (2022)	China	17/16	Chronic pain patients	8–150 Hz music before bedtime	30 min/day for 7 days		LFnu, HFnu, LF/HF, SDNN, RMSSD, PNN50
Epstein et al. (2021) *	Israel	35	Preterm infants with severe brain injury	Maternal singing during music therapy	20 min		LF/HF
Feldman et al. (2016)	USA	24/24	Asthma and panic disorder patients	Combined music therapy	30 min		LF/HF
Hohneck et al. (2021) *	Germany	52	Cancer patients	Body monochord “Heaven & Earth”	15 min		RMSSD
Jeong et al. (2024) *	Korea	10**	Male college students	Fast/slow tempo music during treadmill walking	30 min		SDNN, RMSSD
Kirk and Axelsen (2020)	Denmark	30/30	Adults with stress	Mindfulness app (Headspace)	20–30 min/day for 10 days		LF/HF
Kunikullaya et al. (2015)	India	46/47	Prehypertensive/hypertensive	Raga Bhimpalas on flute	15 min/day for 3 months		LFnu, HFnu, LF/HF, TP, SDNN, RMSSD, PNN50
Lee et al. (2016)	Korea	33/31	University students with stress	Preferred pop/gospel music	20 min		LFnu, HFnu, SDNN
Lee et al. (2017)	China	35/37	Patients awaiting PET scans	Meditative music with “Chi” resonance	30 min		LFnu, HFnu, LF/HF
Li and Dong (2012)	China	30/30	Women undergoing cesarean delivery	Self-selected Chinese classical music pre-surgery	30 min		LF/HF, TP
Lin et al. (2024)	China	32/32	Elderly with poor sleep quality	Binaural beat music	20 min/twice daily for 14 days		LFnu, HFnu, LF/HF, SDNN
Mitsiou et al. (2022)	Greece	10/10	Hemodialysis patients	Preferred music during dialysis	30–60 min	Short-term and 24 h monitor	LFnu, HFnu, LF/HF, SDNN, RMSSD, PNN50
Miyata et al. (2016)	Japan	42/42	Dental fear patients	Self-selected calming music	Until surgery entry		LF/HF
Narayanan et al. (2024)	New Zealand	38/36	Surgeons (vascular/general)	Self-selected background music	Entire surgery		LF/HF, TP, RMSSD
Narayanan et al. (2025) *	New Zealand	15 + 12***	Medical students & vascular surgeons	Self-selected music (Spotify playlists)	During simulated surgery task		LF/HF, TP, SDNN, RMSSD
Peng et al. (2009)	China	30/26	Healthy undergraduates	Soft music (Bandari)	15 min		LFnu, HFnu, LF/HF, TP, SDNN
Ranger et al. (2018) *	Germany	21	Preterm infants	Live pentatonic harp music during skin-to-skin contact	15 min		SDNN, RMSSD, PNN50
Ribeiro et al. (2018)	Brazil	10/11	Mothers of preterm infants	Receptive techniques weekly	30–45 min for 4 weeks		LFnu, HFnu, LF/HF, SDNN, RMSSD, PNN50
Rio-Alamos et al. (2023)	Chile/Spain	16/15	Anxious adults (non-clinical)	Tibetan singing bowls	30 min		RMSSD, PNN50
Wakana et al. (2022)	Japan	28/27	Dental fear patients	Self-selected healing music via headphones	30 min		LF/HF
Wang et al. (2014)	China	20/20	Elderly surgery patients	Soft music	30 min pre-surgery		LF/HF, TP
Xiao et al. (2023)	China	5/5	MCS patients	Live personalized songs by therapist	30 min/session, 5×/week for 4 weeks		LF/HF, TP, PNN50
Yakobson et al. (2021)	Israel/Germany/Denmark	35/31	Preterm infants in NICU	Live music therapy during skinto-skin care	30 min		LF/HF

CG, control group; HF, high frequency; LF, low frequency; MCS, Minimally Conscious State; nu, normalized units; PET, positron emission tomography; RCT, randomized controlled trial; RMSSD, root mean square of successive RR interval differences; SDNN, standard deviation of normal-to-normal RR intervals; TP, total power.

^*Randomized crossover study.

^**The intervention included fast tempo music and slow tempo music, respectively.

^***The study enrolled 15 medical students and 12 vascular surgeons.