Figure 2.

Observed and counterfactual timelines for two example study participants. The top row represents the observed delivery time while the second and third rows represent the counterfactual times under treatment strategies $k_1$ and $k_2$ , respectively. The circles represent the time where treatment is initiated. Note that participant 1 is adherent to strategy $k_2$ at all times ( $S^{k_2}(t)=1$ at all times $t$ ) but only adherent to strategy $k_1$ prior to time $k_1$ since they were not observed to initiate treatment at $k_1$ ( $S^{k_1}(t)=1$ for $t<k_1$ ; 0 thereafter). Participant 2 is adherent to strategy $k_1$ at all times ( $S^{k_1}(t)=1$ at all times $t$ ) but only adherent to strategy $k_2$ prior to time $k_1$ because they initiated treatment at that time ( $S^{k_2}(t)=1$ for $t<k_1$ ; 0 thereafter).