How to read this document
The IGIN ROI calculator answers one question for your hospital: how many hospital-acquired infections would IGIN have to prevent in a year to pay for itself? It then shows what a larger effect would be worth. It does not assert that IGIN prevents a given share of infections; that is a clinical outcome your own surveillance will measure. What the calculator does claim is that the inputs it starts from are defensible, and this document is where we show that.
Every number falls into one of four kinds, marked on each row:
- Published taken directly from a peer-reviewed study or a government or agency dataset, linked in the References.
- Derived calculated from published figures; the derivation is written out.
- IGIN term a commercial term or planning assumption set by IGIN, shown openly so it can be challenged.
- Your input a fact about your hospital that you provide; the calculator only scales from it.
Wherever you can replace a default with your own procurement or infection-prevention figures, the calculator lets you, and your figures take precedence.
How the results are calculated
- Admissions a year = beds × occupancy × 365 ÷ average length of stay
- Infections a year = admissions × infection rate
- Direct infection cost = infections × direct cost per infection
- Machines = the number you set (default about one per 6 beds)
- Gloves bought today = beds × gloves per bed · gloves actually needed = gloves bought × (1 − glove waste) · gloves IGIN dispenses = gloves needed ÷ (1 − IGIN residual waste) · cartridges = gloves dispensed ÷ gloves per cartridge
- Change in consumables spend = cartridges × cartridge price − (gloves bought ÷ 100) × box price
- Annual cost of IGIN = annual machine payment (zero in the cartridge-only model) + change in consumables spend, where the machine payment = machines × machine price × r ÷ (1 − (1 + r)^−years) at cost of capital r, or simply ÷ years when r is 0%. This is the extra spend versus today, before any infection is prevented
- Break-even = annual cost ÷ direct cost per infection, shown to one decimal; also expressed as a share of your infections. The "Show break-even" button moves the slider to the first 0.1% step at or above that share
- What-if: infections prevented = chosen share × infections · saved = prevented × cost per infection · net = saved − annual cost · return on investment = net ÷ annual cost · five-year net = 5 × net (undiscounted, prices held flat). The sensitivity table repeats this at 4 and 2 percentage points below and above the chosen share
- Indirect losses are displayed for scale and never enter the return; penalty and legal exposure are scaled from a 200-bed reference by beds ÷ 200