Adherence to Blended or Face-to-Face Smoking Cessation Treatment and Predictors of Adherence: Randomized Controlled Trial. - Siemer, Lutz; Brusse-Keizer, Marjolein G J; Postel, Marloes G; Allouch, Somaya Ben; Sanderman, Robbert; Pieterse, Marcel E; Ben Allouch, Somaya (Journal of Medical Internet Research, 2020)