Table 5.

Input parameters categories in medical device reliability studies.

Category	Subcategory or input parameter	Description	Outcomes	Articles
Features	Functionality or performance inspection	Device condition		[50]
				[32]
				[60]
	Age	Device age		[42, 45, 47, 52]
				[12, 44]
				[32]
				[37]
				[20]
	Criticality	Device criticality		[45, 48, 49]
	Type of equipment	Device name		[44]
				[32]
	Class	Device classes		[12]
				[47]
	Manufacturer	Device supplier		[32]
Function	Clinical function or intended function	Device function		[12, 42]
				[44, 45, 47–49]
				[37]
				[38]
Performance	Error codes	Error on device		[50]
	Failures and frequency	Occurrence of failures		[50]
				[37]
				[12, 55]
				[48, 49]
	Root cause of failures	Root cause of failures		[55]
	Useful life ratio	The ratio between the age and expected life		[48, 49]
	Service status of every failure mode	Status display on the device		[50]
	Temperature error	Error on temperature		[29]
Operation and maintenance	Action taken/Repair notes	Tasks during repair work		[50]
				[55]
	Time to repair (downtime)	Time is taken during repair		[50]
				[12, 42, 55]
				[47–49]
				[60]
	Commission time	Time is taken for commission work		[55]
	Missed maintenance	Maintenance not to schedule		[48, 49]
	Parts or part usage	Spare parts inventory		[29]
				[42]
				[35, 36]
	Maintenance interval	Frequency of maintenance		[46]
	Maintenance requirement or complexity	Maintenance activity based on device type		[31, 32]
				[2]
				[34–36]
				[48]
				[52]
	Calibration	Calibration work		[31]
Service availability	Availability of support/alternative devices	Availability of backup device or outsource services		[2, 29]
				[32, 34]
				[52]
	Impact of operation	Operational impact		[29]
	Incident history	Incident record		[54]
	No. of bed	Total bed	Management system	[55]
	Distance to nearest hospital	Measured distance	Management system	[55]
	Location	Device location		[31, 35, 36],
			Management system	[60]
Cost	Maintenance cost	Cost for spare parts and maintenance		[12, 42]
Recall and hazards	Recall and hazards	Product recall and hazards		[44, 45, 47, 52]
				[12]
	Risk and safety	Risk and safety are associated with devices		[12]
				[45, 47–49]
				[37]
				[38]
	Detectability	Ability to detect failures		[37]
Utilization	Staff preferences	Staff preferences		[42]
	Utilization coefficient/rate	Average total hours device is used		[29]
				[12]
				[45, 47–49, 52]
				[37]

PM: Preventive Maintenance.