From: Prophylactic lithium treatment and cognitive performance in patients with a long history of bipolar illness: no simple answers in complex disease-treatment interplay
Non-Li group
Li group
Controls
Total
Berlin
6
18
20
44
Dresden
5
2
12
Poznan
10
25
Halifax
8
15
11
34
Neunkirchen
7
27
31
58
53
142