Intention-to-treat analyses showed no significant effects of NRT on abstinence rates at T7 ( OR = 1.54 , 95 % CI = 0.57 , 4.16 ) and validated abstinence rates at T8 ( OR = 0.64 , 95 % CI = 0.21 , 1.93 ) neither after considering compliance nor after adjusting for covariates .