Cost-effectiveness of implant movement analysis in aseptic loosening after hip replacement: a health-economic model

Table 1 Transition probabilities, costs, and QALYs used to populate the base case model of IMA vs X-ray in aseptic loosening of hip implants

	Value
Transition probability
Probability of being loose for aseptic loosening after X-ray	0.7
Probability of being not loose after X-ray	0.15
Probability of uncertain diagnosis after X-ray	0.15
Probability of having revision surgery after diagnosed as loose (X-ray)	0.75
Probability of having another treatment after diagnosed as loose (X-ray)	0.25
Probability of being loose for aseptic loosening after an X-ray (follow-up)	0.3
Probability of being not loose after a second X-ray (follow-up)	0.7
Probability of having revision surgery after diagnosed as loose (X-ray follow-up)	0.75
Probability of having another treatment after diagnosed as loose (X-ray follow-up)	0.25
Probability of being loose after IMA	0.3
Probability of being not loose after IMA	0.7
Probability of having revision surgery after diagnosed as loose (IMA)	0.75
Probability of having another treatment after diagnosed as loose (IMA)	0.25
Costs
X-ray	SEK 1029
Physician visit	SEK 2635
IMA	SEK 9000
Surgery	SEK 152,187
CT	SEK 4353
Follow-up	SEK 5318
Other treatment	SEK 5318

HRQoL estimates—Baseline value assumed equal for all: 0.62
Parameters	6 months	12 months	18 months	24 months	QALYs	Reference
Immediate necessary surgery	0.68	0.74	0.8	0.8	1.465	Konopka et al. [25]
Needed surgery (receiving nothing or other treatment)	0.5672	0.5144	0.4616	0.4088	1.0288	Mota [26]
Necessary surgery delayed 1 year	0.5672	0.5144	0.6308	0.7472	1.198	Mota [26]–Konopka et al. [25]
No surgery, receiving other treatment	0.65	0.65	0.65	0.65	1.2925	Jönsson et al. [27]

SEK: Swedish krona, HRQoL: Health-related quality of life, QALYs: Adjusted Quality Life Years. IMA: Implant Movement Analysis, CT: Computed tomography

ISSN: 1478-7547