Behavioural Activation for Depression; An Update of Meta-Analysis of Effectiveness and Sub Group Analysis Ekers, David ; Webster, Lisa ; Van Straten, Annemieke ; Cuijpers, Pim ; Richards, David ; Gilbody, Simon Abstract Publication: PLoS ONE Pub Date: June 2014 DOI: 10.1371/journal.pone.0100100 Bibcode: 2014PLoSO...9j0100E