11. Adverse events.

Study ID and comparison	Information related to adverse events
Exercise trials
Ashburn 2007 Gait, balance and functional training vs Control	No participants fell while performing the exercise program.
Canning 2015a Gait, balance and functional training vs Control	Two participants had non‐injurious falls during unsupervised exercise at home.
Chivers Seymour 2019 Gait, balance and functional training vs Control	No participants fell while performing the exercise program, and no adverse events were associated with the intervention. 0‐6 months hospitalisations: 9 PDSAFE exercise group participants (1 participant with 2 hospitalisations); 20 control group participants. 6‐12 months hospitalisations: 18 PDSAFE exercise group participants (2 participants with 2 hospitalisations); 21 control group participants (2 participants with 2 hospitalisations).
Gandolfi 2017 Gait, balance and functional training (virtual reality telerehabilitation) vs Gait, balance and functional training (balance training in a facility)	No adverse events were reported during the study.
Gandolfi 2019 Gait, balance and functional training (trunk‐specific exercises) vs Gait, balance and functional training (general exercises)	No adverse events or safety concerns were reported during the study.
Gao 2014 3D exercise (Tai Chi) vs Control	Not reported
Goodwin 2011 Gait, balance and functional training vs Control	No adverse events occurred during the exercise sessions.
Harro 2014 Gait, balance and functional training (cueing training) / Gait, balance and functional training (treadmill‐based gait training)	No adverse events during the intervention.
Li 2012 3D exercise (Tai Chi) / Resistance training vs Control	Tai‐chi (n=65): 3 in class events ‐ 2 falls, 1 muscle soreness or pain; 24 out of class events ‐ 19 falls, 4 low back pain, 1 ankle sprain. Functional strength training (n=65): 14 in class events ‐ 4 falls, 4 muscle soreness or pain, 3 dizziness or faintness, 3 symptoms of hypotension; 41 out of class events ‐ 31 falls, 3 chest pain, 1 hypotension, 4 low back pain, 2 ankle sprains. Stretching (n=65): 9 in‐class events ‐ 5 falls, 1 muscle soreness or pain, 2 dizziness or faintness, 1 symptoms of hypotension; 36 out of class events ‐ 26 falls, 2 chest pain, 2 hypotension, 5 low back pain, 1 ankle sprain. Nb ‐ out of class events are those that occurred during habitual activity or during an assessment. Participants did not perform any intervention outside the class.
Martin 2015 Gait, balance and functional training vs Control	Not reported
Mirelman 2016 Gait, balance and functional training (virtual reality treadmill training) vs Gait, balance and functional training (treadmill‐based gait training)	No serious adverse events during training. Adverse events other than those that occurred during intervention were recorded for both groups, but were not reported separately for the participants with Parkinson's disease.
Munneke 2010 Other exercise (ParkinsonNet therapists) / Other exercise (standard therapists)	None reported, though not collected systematically.
Paul 2014 Resistance training (muscle power training) vs Control	Power training (n=20): 1 exacerbation of pre‐existing low back pain, 1 pelvic fracture unrelated to the intervention, and 6 participants required modification to training loads due to transient pain, joint inflammation or illness. Control low intensity exercise (n=20): 2 participants had exacerbations of pre‐existing hernias, though this was not attributable to the low intensity exercise.
Pelosin 2017 Gait, balance and functional training (treadmill training at high frequency) vs Gait balance and functional training (treadmill training at intermediate frequency) vs Gait, balance and functional training (treadmill training at low frequency)	Not reported
Penko 2019 Gait, balance and functional training (Gait and cognitive training practised together) vs Gait, balance and functional training (Gait and cognitive training practised separately)	Not reported
Protas 2005 Gait, balance and functional training vs Control	Not reported
Ricciardi 2015 Gait, balance and functional training (best side therapy) / Gait, balance and functional training (worst side therapy) / Gait, balance and functional training (standard therapy)	Not reported
Sedaghati 2016 Gait, balance and functional training (with a balance pad) / Gait, balance and functional training (without a balance pad) vs Control	Not reported
Shen 2015 Gait, balance and functional training / Resistance training	No adverse events related to the intervention in either group.
Smania 2010 Gait, balance and functional training / Flexibility exercise	Not reported
Song 2018 Gait, balance and functional training vs Control	Adverse events were reported for the intervention group. Six participants ceased the stepping training: two ceased exercise due to it exacerbating pre‐existing lower back pain; two died; one sustained a knee injury from a fall unrelated to the intervention; one ceased for personal reasons. Additionally, one participant experienced a non‐injurious fall while undertaking the intervention and eight participants reported an increase in pre‐existing pain (e.g. lower back pain, knee pain, foot pain) but felt that the exacerbation was unrelated to the intervention.
Thaut 2019 Gait, balance and functional training (rhythmic auditory stimulation training throughout intervention period) vs Gait, balance and functional training (rhythmic auditory stimulation training with no training in middle 8 weeks of intervention period)	Participants who dropped out did so for reasons unrelated to adverse events.
Volpe 2014a Gait, balance and functional training (with proprioceptive stabiliser) / Gait, balance and functional training (without proprioceptive stabiliser)	No major adverse event related to the intervention.
Volpe 2014b Gait, balance and functional training (hydrotherapy) / Gait, balance and functional training (land‐based therapy)	Not reported
Wong‐Yu 2015 Gait, balance and functional training vs Control	No adverse events related to the intervention.
Medication trials
Chung 2010 Donepezil vs placebo	Donepezil (n=23): Eight participants (35%) reported 16 side effects (e.g. dehydration, gastrointestinal upset, headache, sleep disturbance, muscle cramps, orthostatic hypotension, weight loss). Placebo (n=23): Five participants (22%) reported 6 side effects (e.g. gastrointestinal upset, headache, sleep disturbance). These side effects were reported to be transient in most cases.
Henderson 2016 Rivastigmine vs placebo	Rivastigmine (n=64): 187 adverse events (excluding falls) Placebo (n=65): 122 adverse events (excluding falls) Adverse events included cardiac disorders, endocrine disorders, gastrointestinal disorders, general disorders and administration site disorders, immune system disorders, infections and infestations, injury, poisoning and procedural complications, investigations, metabolism and nutrition disorders, musculoskeletal and connective tissue disorders, neoplasms benign, malignant and unspecified, nervous system disorders, psychiatric disorders, renal and urinary disorders, respiratory, thoracic and mediastinal disorders, skin and subcutaneous tissue disorders, surgical medical procedures, vascular disorders. About one third of participants in the rivastigmine group complained of nausea. Most adverse events were categorised as mild and were considered to be unrelated to the intervention. There were 27 adverse events that were classified as serious; 14 in the rivastigmine group and 13 in the placebo group. Two of these events in the rivastigmine group were considered to be probably related to the rivastigmine. Twenty‐three participants in the rivastigmine group and 19 participants in the placebo group stopped taking the trial medication due to adverse events.
Li 2015a Rivastigmine vs placebo	Two participants withdrew due to adverse reactions, however details not provided.
Education trial
Ward 2004 Personalised education vs control (standardised printed information)	Not reported
Exercise plus education trials
Cattaneo 2019 Gait, balance and functional training plus education vs Control	Not reported
Morris 2015 Resistance training / Gait, balance and functional training (movement strategy training) vs Control	Functional strength training group (n=70): 25 occasions of new muscle soreness lasting > 24 hours Movement strategy training group (n=69): 11 occasions of new muscle soreness lasting > 24 hours, 1 fall and 2 occasions of dizziness during the intervention.
Morris 2017 Gait, balance and functional training vs Control	No adverse events related to the intervention.