Power, R A
Verweij, K J H
Zuhair, M
Montgomery, G W
Henders, A K
Heath, A C
Madden, P A F
Medland, S E
Wray, N R
Martin, N G
Article History
Received: 22 January 2014
Revised: 18 March 2014
Accepted: 22 April 2014
First Online: 24 June 2014
Competing interests
: The authors declare no conflict of interest.