Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Neurological disability
RCT	31 adults	Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS)-Severity score 4 weeks 0.27 with botulinum A toxin 125 U/mL 1.07 with botulinum A toxin 500 U/mL	P = 0.19		Not significant
RCT	31 adults	TWSTRS-Disability score 4 weeks 2.6 with botulinum A toxin 125 U/mL 1.2 with botulinum A toxin 500 U/mL	P = 0.26		Not significant
RCT	31 adults	TWSTRS-Total score 4 weeks 5.6 with botulinum A toxin 125 U/mL 4.4 with botulinum A toxin 500 U/mL	P = 0.63		Not significant