Average drug doses in the peripheral lung, central lung, and extrathoracic airway; residual drug left in the device; and residual drug that was exhaled for the 3 study populations. Average drug doses in the peripheral lung, central lung, and extrathoracic airway; residual drug left in the device; and residual drug that was exhaled for the 3 study populations. Individual deposition values were rounded to one decimal place and therefore do not total 100% for each group. From Reference 79, with permission. Beth L Laube Respir Care 2015;60:806-824 (c) 2012 by Daedalus Enterprises, Inc.