The mean ( SEM ) weight change was -4.7 0.5 kg for the NND compared with -1.5 0.5 kg for the ADD ( adjusted difference : -3.2 kg ; 95 % CI : -4.6 , -1.8 kg ; P < 0.001 ) for the completer analysis , and the difference was -3.0 kg ( 95 % CI : -4.0 , -2.1 kg ) for the intention-to-treat analysis .