Table 1. Primary characteristics of the 35 included studies.

	All studies, n = 35
Designa
Placebo-controlled, n (%)	16 (46)
Active-controlled, n (%)	11 (31)
Different doses, n (%)	14 (40)
Not randomized, n (%)	10 (29)
Number of arms
1, n (%)	7 (20)
2, n (%)	14 (40)
3, n (%)	14 (40)
Type
Phase 2, n (%)	3 (9)
Phase 3, n (%)	17 (49)
Others, n (%)	15 (43)
Technique
BPF, n (%)	9 (26)
SIENA, n (%)	17 (49)
Other, n (%)	9 (26)

^aOne study could be in two designs.

BPF: Brain Parenchymal Fraction; SIENA: Structural Image Evaluation, using Normalisation, of Atrophy.