Figure 1.

Observed and estimated mean scores for an immortal cohort (without single imputation). The figure displays the observed and estimated mean scores for arm A (upper panel) and arm B (lower panel) when considering an immortal cohort. Single imputation has not been applied. The black solid-line curve corresponds to the arithmetic average of the observed score values, the blue dotted-line curve corresponds to the IPW method, the green dash-dotted-line curve corresponds to the LI method, and the red dashed-line curve corresponds to the MP method.