Table 1.
Model framework and clinical parameters
| Parameter | Base case value (sensitivity analysis [range]) | Reference |
|---|---|---|
| Model framework | ||
| Time horizon (years) | 6 (1–6) | 15,16 |
| Size of cohort | Per patient Per 1,000 patients |
NA |
| Payer mix | ||
| Private payer (%) | 51.5 (0–100) | 26,27 |
| Medicaid (%) | 48.5 (0–100) | |
| Discount rate (% per annum) | 3.00 (0.00–5.00) | 14 |
| TGR lengthening setting of care | ||
| Hospital outpatient/inpatient (%) | 45.8 (0.0–100.0)/54.2 (0.0–100.0) | |
| Hospital inpatient 1-day short stay (%) | 55.5 | 22 |
| Hospital inpatient standard ward (%) | 35.2 | |
| Hospital inpatient ICU (%) | 9.3 | Clinical practice dataa |
| MCGR lengthening setting of care | ||
| Physician office (%) | 100.0 | b |
| Device failures and SSIs | ||
| TGR device failure (% per month) | 0.59 (0.20–1.26) | 15,16 |
| MCGR device failure (% per month) | 0.37 (0.00–0.59) | |
| Device failures requiring complete removal (vs partial) (%) | 5.8 (2.9–11.6) | 18b |
| SSI (% per invasive surgery) | 2.34 (1.17–4.68) | 18 |
| Deep SSI (vs superficial) (%) | 68 (34–100) | 7,8,18,28–35 |
| Other risk factors | ||
| Device failure: single rods (vs dual rods), RR | 2.64 (1.32–5.28) | 18 |
| SSI: Medicaid patients (vs all other patients), RR | 2.06 (1.19–3.58) | 36 |
Notes:
a
Estimate based on experience at one facility where three of 41 patients (conservatively, ~5%) had an ICU stay, whereby half were undergoing the lengthening on an inpatient basis and the other half on an outpatient basis.
b
Clinical advisors.
Abbreviations: ICU, intensive care unit; MCGR, magnetically controlled growing rod; NA, not applicable; RR, relative risk; SSI, surgical site infection; TGR, traditional growing rod.