Table 1.

Failure modes and accompanying RPN scores for identified failure modes for a standard treatment with and without a Record and Verify system

Failure mode	Impact	RPN with record and verify (occurrence, detectability, severity)	RPN with no record and verify (occurrence, detectability, severity)	Percent increase (%)
Dose not recorded, fraction repeated	Overtreatment	126 (3, 6, 7)	392 (7, 8, 7)	211
Wrong patient brought from waiting room for treatment	Patient treated with wrong plan	140 (5, 4, 7)	294 (7, 6, 7)	110
Patient does not show up for treatment	Gap in treatment	245 (7, 7, 5)	280 (7, 8, 5)	140
Wrong beam modifier	Wrong dose to patient	224 (7, 8, (4)	224 (7, 8, 4)	0
Beam interruption	One beam not delivered, partial under- or overdose	64 (8, 2, 4)	224 (8, 7, 4)	250
Proper IGRT not performed	Patient not aligned correctly	96 (4, 4, 6)	216 (6, 6, 6)	225
Patient wrongly aligned during image alignment	Dose delivered to wrong location	168 (6, 4, 7)	210 (6, 5, 7)	25
Patient arrival not communicated, missed treatment	Gap in treatment	60 (6, 2, 5)	210 (6, 7, 5)	250
Wrong positioning applied	Patient in wrong position	180 (6, 6, 5)	180 (6, 6, 5)	0
Wrong plan pulled up for the right patient	Patient treated with wrong plan	84 (3, 4, 8)	168 (6, 4, 7)	100
Partial treatment missed	Partial underdose	60 (3, 4, 5)	105 (3, 7, 5)	75
Patient not sent for clinic visit	Missed clinic visit	72 (8, 9,1)	81 (9, 9, 1)	12
Pacemaker not monitored according to instructions	Pacemaker not monitored	10 (1, 10, 1)	30 (3, 10, 1)	300
Patient came back twice in same day	Exceeded daily dose	4 (1, 1, 4)	16 (1, 4, 4)	300
Average ± SD		110 ± 74	188 ± 103	71

Abbreviations: IGRT = Image Guided Radiation Therapy; RPN = Risk Priority Number.

The rows are ordered in order of highest to lowest RPN score for the situation with no record and verify system availability.