user error is a growing problem with home care devices. one factor that contributes to the increase in these errors is the difficulty that lay users have understanding the instruction manuals provided with devices. most current user instruction manuals are written for health care professionals. when the device is dispensed for home use, lay users may not receive adequate instructions on its use or have the appropriate education and experience that the professional users of medical devices have. therefore, it is essential that home use device instruction manuals be developed for lay users. this booklet is designed to assist manufacturers of home use devices to plan and write their manuals for lay users.