Distribution of explanatory variables between patients receiving influenza vaccine and those not receiving influenza vaccine for propensity score quintiles ranging from 1 (least likely to receive influenza vaccine) to 5 (most likely to receive influenza vaccine).

<p>Distribution of explanatory variables between patients receiving influenza vaccine and those not receiving influenza vaccine for propensity score quintiles ranging from 1 (least likely to receive influenza vaccine) to 5 (most likely to receive influenza vaccine).