Primary analysis
CPD, heaviness, SE
Participants smoked fewer cigarettes per day from packs of 20 cigarettes (Number of cigarettes smoked per day and motivation to stop smoking.CI, confidence interval; SD, standard deviation.Unadjusted;adjusted for pre‐specified covariates (baseline consumption and heaviness of smoking at enrolment);

Motivation To Stop Smoking Scale [range = 1 (I do not want to stop smoking) to 7 (I REALLY want to stop smoking)]; Data were analysed with no imputation for missing values (and without any of the assumptions required for this); Data were analysed as per the primary analysis, but missing values imputed for up to two cigarette packs classed as Primary‐missing; Data were analysed as per the primary analysis, with an additional covariate: self‐reported mitigating factors impacting on cigarette consumption; After adjusting for pre‐specified covariates (baseline consumption and heaviness of smoking at enrolment) modelling (Primary (When including the interaction term, cannot include the period otherwise terms are aliased.CI, confidence interval.CPD = cigarettes smoked per day;MTSS = motivation to stop scale (range = 1–7);HSI = heaviness of smoking index (range = 0–6); SE = standard error.