Table 1. Randomized controlled trials of Tai Chi (TC) that include reporting of adverse events (Aes) (n= 50).

Population Author last name (Year)	Interventions type; dose; sample size (n)	AE Protocol included (Y/N)? If Y, All groups observed (Y/N)? AE information source (s)? Frequency of monitoring?	AEs reported by author	AEs reported for all groups (Y/N)?
Healthy adults
Irwin et al (2008)56	TC: 40 min, 3x/wk for 16 wks followed by practice for 9 more wks (n= 59) Health education; 40 min, 3x/wk for 16 wks followed by a 9 wk assessment (n= 53)	N	“No AEs associated with either intervention.”	Y
Li et al (2004)32	TC: 8-form Yang style; 60 min, 3x/wk for 24 wks (n= 62) Low-impact exercise; 60 min, 3x/wk for 24 wks (n= 56)	Y Not specified Study staff, instructors Each class	“No exercise-related injuries…”	Not specified
Liu et al (2012)20	TC: 24-form, Yang style; 45 mins, 2x/wk for 16 wks (n= 20) Proprioception exercise: Static and dynamic balance exercises; 45s, 2x/wk for 16 wks (n= 20) No structured exercise (n= 20)	N	“No discomfort while testing; no discomfort while practicing Tai Chi.”	N (TC only)
Nedeljkovic et al (2012)21	TC: Taiji, 18 sequence of 37 Chen Man-Ch'ing Yang style; 60 min, 2x/wk for 12 wks (n= 35) Wait-list (n= 35)	N	“No AEs of the Taiji training were observed.”	N (TC only)
Wolfson et al (1996)19	Balance Training (B): 45 min, 3x/wk for 3 months (n= 28) Strength Training (S): 45 min, 3x/wk for 3 months (n= 28) Balance + Strength Training (B+S): 90 min, 3x/wk for 3 months (n= 27) Education; usual activities (n= 27) All groups then received TC: 60 min, 1x/wk for additional 26 wks	Y Not specified Instructors, study staff Each exercise class	“Musculoskeletal complaints developed in 10 of 55 subjects in the S and B+S groups.”	N (AEs not reported during TC training)
Impaired balance, musckuloskeletal health, reduced physical function
Day et al (2012)22	TC: Modified 46-form Sun style; 60 min, 2x/wk for 24 wks (n= 250) Stretching and flexibility: 60 min, 2x/wk for 24 wks (n= 253)	N	“There were 6 AEs, 5 of which were among intervention participants.” 4 associated with testing protocol. “1 participant became unwell at a TC class because of a medical condition.”	N (TC only)
Dechamps et al (2009)57	TC: Modified Yang style for elderly; 30 min, 4x/wk for 24 wks (n= 26) Cognition-action: 30 min progressing to 40 min, 2x/wk for 24 wks (n= 26)	N	“4 participants were hospitalized for health-related causes independent of training (n = 4 in TC)…”	Y
Dechamps et al (2010)42	TC: Adapted variations of Yang style for elderly; 30 min, 4x/wk for 6 months (n= 51) Cognition-action: 30-45 min, 2x/wk for 6 months (n= 49) Control: Usual care (n= 60)	N	“None of the observed deaths (n=18) was directly or indirectly attributable to an AE due to the intervention.”	Not specified
Li et al (2004)33	TC: 24-form Yang style; 60 min, 3x/wk for 6 months (n= 125) Exercise stretching; 60 min, 3x/wk for 6 months (n= 131)	Y Not specified Study staff, instructors Each class	“No exercise-related injuries occurred…”	Not specified
Li et al (2005)43	TC: 24-form, Yang style; 60 min, 3x/wk for 6 months (n= 125) Stretching, including controlled breathing and relaxation; 60 min, 3x/wk for 6 months (n= 131)	N	“No intervention-related injuries or falls reported…”	Not speicified
Li et al (2012)58	TC: Modified 8 form routine; 60 min, 2x/wk for 24 wks (n= 65) Resistance Training: strengthening muscles, 8-10 exercises with a weighted vest and ankle weights; 60 min, 2x/wk for 24 wks (n= 65) Stretching; 60 min, 2x/wk for 24 wks (n= 69)	N	“No serious AEs were observed during tai chi training..” TC: In class (2 falls, 1 muscle soreness or pain); Out of class (19 falls, 4 low back pain, 1 ankle sprain) Resistance: In class (4 falls, 4 muscle soreness or pain, 3 dizziness or faintness, 3 symptoms of hypotension); Out of class (31 falls, 3 symptoms of chest pain or discomfort, 1 symptoms of hypotension, 4 low back pain, 2 ankle sprains) Stretching: In class (5 falls, 1 muscle soreness or pain, 2 dizziness or faintness, 1 symptoms of hypotension); Out of class (26 falls, 2 symptoms of chest pain or discomfort, 2 symptoms of hypotension, 5 low back pain, 1 ankle sprain)	Y
Ming-Chien et al (2010)23	TC: 24-form, Yang style; 60 min, 3x/wk for 24 wks (n= 30) No exercise intervention (n= 31)	N	“Sporadic complaints of minor muscle soreness and foot and knee pain…during the first few days of the intervention.”	N (TC only)
Sattin et al (2005)59	TC: Modified Yang style; 60 min and progressing to 90 min, 2x/wk over the course of 48 wks (n= 158) Wellness Education (WE); 60 min, 1x/wk for 48 wks (n= 153)	N	“No AEs occurred during the TC or WE intervention. One participant sustained an ankle abrasion during the medical evaluation.”	Y
Shen et al (2010)45, 67	Placebo + TC: 500 mg medicinal starch daily and 24-form Yang style; 60 min, 3x/wk for 24 wks (n= 42) Green Tea Polyphenol (GTP) + TC: 500 mg GTP daily and 24-form Yang style; 60 min, 3x/wk for 24 wks (n= 38) GTP: 500 mg GTP daily for 24 wks (n= 47) Placebo: 500 mg medicinal starch daily for 24 wks (n= 44)	Y Y Participants, study staff, instructors, blood markers At baseline and every 4 wks throughout the study period	“Four participants reported AEs during the study. One subject in the Placebo arm experienced nausea and diarrhea…One subject in the GTP arm had elevated AST and ALT levels…One subject in the Placebo + TC arm reported having retinal bleeding on a non-exercise day and another subject in the Placebo + TC arm reported having a broken wrist on a non-exercise day…These four reports, as judged by the safety monitoring team, were unlikely related to the study protocol. No AEs due to TC was observed or reported in this study…sporadic complaints about muscle soreness during the first two weeks.”	Y
Taylor et al (2012)53	TC: 10-form Sun style; 60 min, 1x/wk for 20 wks (n= 233) TC: 10-form Sun style; 60 min, 2x/wk for 20 wks (n= 220) Low-level exercise; 60 min, 1x/wk for 20 wks (n= 231)	Y Not specified Participants At end of intervention	“No serious AEs resulting from participation in any of the exercise programs. When asked whether participation in the program caused any problems, 11 (Low Level Exercise), 19 (TC 1) and 15 (TC 2) reported problems. The most commonly reported problem was an increase in aches and pains (4 Low Level Exercise, 4 TC 1 and 3 TC 2).”	Y
Wayne et al (2012)49	TC: Pragmatic (community TC classes); 60 min, 2x/wk for 1 month, then 1x/wk for 8 months; >=30 min home practice or additional classes 2x/wk for 1st month and 3x/wk for remaining 8 months (n= 43) Waitlist; (n= 43)	Y Y Study staff, instructors, participants Monthly	“No serious AEs. A total of nine minor AEs were reported. Seven in the TC group and two in the control group. Reports in both groups were largely musculoskeletal related (e.g. shoulder or back pain); none in the TC were attributed directly to TC training.”	Y
Wolf et al (2003)55	TC: 6 out of 24 moves; 60 min progressing to 90 min, 2x/wk for 48 wks (n= 145) Wellness education; 60 min, 1x/wk for 48 wks (n= 141)	Y Not specified Not specified Not specified	“…no AEs occurred during the TC or Wellness Education intervention.”	Y
Adults with chronic pain
Abbott et al (2006)41	TC: 24-form Yang style; 60 min, 2x/wk for 15 wks (n= 24) Waitlist; (n= 23)	N	“No participant reported an adverse effect from the intervention.”	Not specified
Brismee et al (2007)17	TC: 24-form Yang style; 40 min, 3/wk for 6 wks, then 6 wks of home-based TC training (n=22) Health lectures; 40 min, 3/wk for 6 wks, then 12 wks of no activity (n=19)	Y N (TC only) Participants, instructors Each class	“Sporadic complaints of minor muscle soreness and foot and knee pain were made mainly during the first few days of the intervention.”	N (TC only)
Fransen et al (2007)24	TC: Modified 24-form Sun style; 60 min, 2x/wk for 12 wks (n= 56) Hydrotherapy: 60 min, 2x/wk for 12 wks (n= 55) Waitlist; (n= 41)	N	“11 participants reported a serious AE requiring hospitalization. None…could be related to the interventions. One participant withdrew from hydrotherapy and one withdrew from TC due to exacerbation of low back pain.”	N (TC + Hydrotherapy)
Hall et al (2011)16	TC: TC for Health Program; 40 min, 2x/wk for 8 wks, then 1x/wk for 2 wks (n= 80) Waitlist, usual health care (n= 80)	Y Y Participants Not specified	“Three people discontinued treatment after 3 weeks due to medical complications not associated with the intervention…Three participants reported a small initial increase in back pain symptoms that were alleviated by the third or fourth week of treatment, and 1 participant reported an increase in upper back pain that was alleviated once they corrected upper extremity posture.”	N (TC only)
Jones et al (2012)44	TC: Simplified 8-form Yang style; 90 min, 2x/wk for 12 wks (n= 51) Education; 90 min, 2x/wk for 12 wks (n= 50)	N	“No AEs were observed.”	Not specified
Ni et al (2010)30	TC: 24-form Yang style; 30 min, 2x/wk for 8wks, 3x/wk for 8 wks, 4x/wk for 8 wks (n= 18) Wellness education and stretching; 45 min, 1x/wk for 24 wks (n= 17)	Y Y Not specified Weekly	“No AEs were reported, though in 5 patients, sporadic complaints of minor muscle soreness and foot and knee pain were made mainly during the first few days of the intervention.”	Not specified
Song et al (2003)25	TC: 12 move Sun style (TC for Arthritis by Dr. Paul Lam); 3x/wk for 2 wks with a instructor or by themselves, then supervised 1x/wk, home practice 20 min/day, 3x/wk for 10 wks recorded in a exercise log (n= 38) Waitlist (n= 34)	N	“…slight soreness of the knee and leg muscles was reported during the first week of exercise…”	N (TC only)
Wang et al (2009)54	TC: 10-form Yang style; 60 min, 2x/wk for 12 wks, 20 min of home practice daily (n= 20) Wellness education and stretching; 60 min, 2x/wk for 12 wks, 20 min of home stretching daily (n= 20)	Y Not specified Study staff Not specified; medication use at each study visit	“One participant in the TC group reported an increase in knee pain at the 2-week assessment. This was resolved following modification of the participant's TC techniques. One participant in each assignment group reported newly diagnosed cancer (1 breast cancer, 1 colon cancer) during the 12-week intervention period.”	Y
Wang et al (2010)31	TC: 10 form Yang-style; 60 min, 2x/wk for 12 wks, home practice ≥ 20 min daily (n=33) Wellness Education and stretching; 60 min, 2x/wk for 12 wks, home practice 20 min daily (n= 33)	Y Y Study staff Each study visit	“No AEs were reported.”	Not specified
Metabolic, cardiovascular, and immune disorders
Barrow et al (2007)60	TC: Wu Chian Chuan (Orchid Hand 21) style; 55 min, 2x/wk for 16 wks (n= 32) Standard medical supervision and drug treatment (n= 33)	N	“No AEs occurred in the TC sessions…one patient in the intervention and one in the control withdrew due to worsening heart failure symptoms. Two patients in the control withdrew because of worsening co-morbidities. One patient died in the intervention and two died in the control.”	Y
Caminiti et al (2011)61	TC: 10-move Yang style + endurance training (ET) on different days; 30 min, 3x/wk for 12 wks (n= 30) Endurance training; 30 min, 3x/wk for 12 wks (n= 30)	N	“No patients had AEs during the exercise protocol. Worsening HF occurred in 1 patient of the ET group and was managed only by increasing the dose of furosemide.”	Y
Chan et al (2010)34	TC Qigong (TCQ): 13 move of Breathing Regulating TCQ; 60 min; 2/wk for 3 months (n= 70) Exercise: Breathing and walking; self practice for 1 h everyday + community gatherings weekly for 3 months (n= 69) Maintain routine activities + community gatherings weekly for 3 months (n= 67)	N	“…during the intervention, no exercise related problems occurred.”	Not specified
Chen et al (2010)35	TC: Simplified Chen style; 60 min, 3x/wk for 12 wks, given a DVD for home practice (n= 62) Aerobic exercises (aerobic dance) 60 min, 3x/wk for 12 wks plus home based exercises (n=55)	N	“…very few adverse reactions or injuries were reported.”	Not specified
Dechamps et al (2008)36	TC + diet: Modified Yang style; 120 min, 1x/wk for 10 wks (n= 11) Conventional structured exercise program + diet: 120 min, 1x/wk for 10 wks (n= 10)	N	“No AEs occurred during this study.”	Not specified
Hart et al (2004)62	TC: 60 min, 2x/wk for 12 wks (n= 9) Physiotherapy exercises focused on improvement of balance; 60 min, 2x/wk for 12 wks (n= 9)	N	“No side effects were seen in either group.”	Y
Jung et al (2012)26	TC: 20 move, developed by Dr. Paul Lam; 60 min, 3x/wk for 12 wks + home practice logs (n= 28) Waitlist (n= 28)	N	“No adverse effects associated with the practice of TC were reported.”	N (TC only)
Leung et al (2012)27	TC: 21-form, Sun style ("TC for Arthritis"); 60 min, 2x/wk for 12 wks, home practice 30 min/day, 5x/wk (n= 22) Usual care; no exercise training (n= 20)	N	“…no AEs reported.”	N (TC only)
Sato et al (2010)37	TC + conventional cardiac rehabilitation: 8 move, Yang style; 60 min, 1x/wk, home practice 3x/wk for 1 yr (n= 10) Conventional cardiac rehabilitation and routine care for 1 yr (n= 10)	N	“During the study…no clinical events were recorded.”	Not specified
Taylor-Piliae et al (2012)28	TC: 24-form, Yang style; 60 min, 3x/wk for 12 wks (n= 16) Given information for participating in community-based physical activity for older adults (n= 12)	N	“There were no falls or other AEs during TC classes.”	N (TC only)
Tsai et al (2003)29	TC: 108-form Yang style; 50 min, 3x/wk for 12 wks (n= 37) Sedentary; maintain usual lifestyle behaviors (n= 39)	N	“None of the subjects experienced angina, major ventricular arrhythmias, or significant myocardial ischemia during the TC exercise.”	N (TC only)
Tsang et al (2007)46, 47	TC: 'hybrid' form,' 12 move Sun and Yang style; 60 min, 2x/wk for 16 wks (n= 18) Sham exercise; 60, 2x/wk for 16 wks (n= 20)	Y Y Study staff Weekly	“There were no exercise-related AEs, and no group differences in acute health problems. During the…study, diabetic medication was commenced by one TC, and ceased in one control participant.” “One subject (with pre-existing spinal stenosis) in TC found the exercise intolerable secondary to pain and fatigue, and did not attend after session 1…Over the 16 weeks 0 (0-2) falls per person were reported in TC, and 0 (0-2) in the controls (p= 0.2).”	Y
Tsang et al (2010)48	TC: 24-form, Yang style; 60 min, 3x/wk for 6 months (n= 8) Kung Fu: 60 min, 3x/wk for 6 months (n= 12)	Y Y Participants, study staff Weekly	“Most AEs not related to study participation (99%). There were no significant differences between groups in AEs, whether they were related to study participation (KF: 0 (0–2) versus TC: 0 (0–0); P = .30)), or not (KF: 13.9 ± 9.6 versus TC: 7.1 ± 4.2; P = .08)…AEs occurred in 2 KF participants only, where both participants fell during the jogging/star-jump-type exercise warm-up. 1 participants also reported knee pain…”	Y
Wang et al (2008)63	TC: Yang style; 60 min, 2x/wk for 12 wks, instructed to practice at least 20 min, 1x/day at home (n= 10) Stretching and wellness education; 60 min, 2x/wk for 12 wks, instructed to practice at least 20 min, 1x/day at home (n= 10)	N	“There were no AEs associated with TC or education and stretching training during the 12-week study period.”	Y
Wang et al (2010)38	TC: Yang style; 50 min, 1x/wk for 12 wks (n= 17) Rehabilitation: 80 min (non-resistance 20 min + resistance 60 min), 1x/wk for 12 wks (n= 17)	N	“…no mental and/or physical AEs were reported…”	Not specified
Yeh et al (2004)50	TC: 5 moves, short form Yang style; 60 min, 2x/wk for 12 wks, videotape home practice ≥ 3x/wk (n= 15) Waitlist, usual care; 12 wks (n= 15)	Y Y Study staff At follow up visits	“No AEs occurred during the TC sessions. One patient in the intervention group and 4 in the control group were hospitalized during the study period for exacerbation of symptoms of heart failure…”	Y
Yeh et al (2010)51	TC: short form Yang style + Usual Care; 60 min, 2x/wk for 12 wks, encouraged (not required) 35 min instructional videotape home practice ≥ 3x/wk (n= 5) Control: Waitlist, usual care (n= 5)	Y Y Study staff At follow up visits	“No AEs occurred during the class sessions. No patients in either group were hospitalized during the study period for COPD exacerbation, and there were no deaths.”	Y
Yeh et al (2011)52	TC: short form Yang style; 60 min, 2x/wk for 12 wks, 35 min instructional videotape home practice > 3x/wk (n= 50) Heart health education program; 60 min, 2x/wk for 12 wks (n= 50)	Y Y Study staff At follow up visits	“…no AEs related to the protocol. However, we documented several events during the study period, including 3 deaths (in the education), 6 hospitalizations (HF exacerbation/angina/shortness of breath: 2 in the TC and 4 in the education), 2 arrhythmias in TC, 2 episodes of syncope in education, and 3 falls (2 in TC and 1 in education).”	Y
Yeh et al (2012)39	TC: 5-move, Yang style; 60 min, 2x/wk for 12 wks, encouraged to practice at home 3x/wk, provided with a 35 min instructional videotape (n= 8) Aerobic Exercise; 60 min, 2x/wk for 12 wks, encouraged to practice at home 3x/wk, provided with a 35 min instructional videotape (n= 8)	N	“No AEs or hospitalizations occurred during class sessions or the study period.”	Not specified
Zhang et al (2008)64	Tai Ji Quan: 24 style, short form; 60 min, 5x/wk for 14 wks (n= 10) Free activity program; 60 min, 5x/wk for 14 wks (n= 10)	N	“In the study, there were no serious AEs or development of diabetic complications…as a result of the exercise intervention…one participant in the control had a cerebrovascular accident during the experimental period and was withdrawn from the study.”	Y
Adults with cognitive deficites or mood disorders
Lam et al (2011)66	TC: simplified 24-form; induction phase- with instructor 1x/wk for 8-12 wks, maintenance phase- no instructor ≥ 3x/wk for ≥ 30 min each time using a video up to 1 yr (n= 171) Control: Muscle stretching exercise; induction phase- with an instructor 1x/wk for 8-12 wks, maintenance phase- no instructor ≥ 3x/wk for at ≥ 30 min each time using a video up to 1 yr (n= 218)	N	“1 subject in the control group had a fall with minor injury. No other AEs reported.”	N (Control only)
Lavretsky et al (2011)40	Tai Chi Chih: 2 h, 1x/wk for 10 wks + 10-20 mg/day of escitalopram for 16 wks (n= 36) Health education; 2 h, 1x/wk for 10 wks + 10-20 mg/day of escitalopram for 16 wks (n= 37)	N	“We did not observe any serious AEs. Common mild-to-moderate side-effects attributable to the medication included nausea, diarrhea, excessive sedation, daytime sleepiness, and rash.“	Not specified
Tsai et al (2012)65	TC: 12-form Sun style (TC for Arthritis); 20 min gradually progressing to 40 min/, 3x/wk for 20 wks (n= 28) Health education; 20-40 min, 3x/wk for 20 wks (n= 27)	N	“No AEs were found in either group.”	Y
Yeung et al (2012)18	TC: 1st section of 108 moves Yang; 60 min, 2x/wk for 12 wks and 3x/wk home practice (n= 26) Waitlist (n= 13)	Y N (TC only) Instructors Each class	“No AEs due to the TC intervention were reported…”	N (TC only)