Table 7.

Studies with CBD addressing quality of life in PD

Symptom	Design	Sample size	Duration	Primary outcome	Application form	Dosage	Outcome	References
QOL	Double-blind, randomized, placebo-controlled crossover study	17	2 × 4 weeks, 2 weeks wash-out phase	PDQ-39a	Orally	2.5 mg THC + 1.25 mg CBD (Cannador) or placebo	No positive effect on quality of life	Carroll et al. [89]
	Explorative, randomized, double-blind, placebo-controlled	21	6 weeks	PDQ-39a	Orally	75 or 300 mg CBD or placebo	Significant improvement of quality of life (300 mg CBD group)	Chagas et al. [84]
	Randomized double-blind, placebo-controlled clinical trial	33	14 weeks	PDQ-39a	Orally	75 or 300 mg CBD or placebo	No significant effect between groups	de Almeida et al. [86]

^aParkinson’s Disease Questionnaire-39.