Bladder Outlet Obstruction Index (BOOI)
Bladder outlet obstruction index (Abrams 1999): BOOI = PdetQmax - 2 x Qmax and BCI = PdetQmax + 5 x Qmax; pressure-flow indices of obstruction and detrusor contractility.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Detrusor pressure at max flow
- 80 cmH2O
- Maximum flow rate
- 10 mL/s
Result: Bladder outlet obstruction index 60 — obstructed (> 40); BCI 130 (normal contractility).
The tool opens with these values already filled in. Replace them with your own.
What the result means
- BOOI < 20 / 20-40 / > 40
- Unobstructed / equivocal / obstructed (PdetQmax - 2 x Qmax).
- BCI < 100 / 100-150 / > 150
- Weak / normal / strong contractility (PdetQmax + 5 x Qmax). Pressure-flow indices, not a diagnosis.
What you enter
- Detrusor pressure at max flow (PdetQmax)
- Maximum flow rate (Qmax)
How this is calculated
Abrams P. Bladder outlet obstruction index, bladder contractility index and bladder voiding efficiency: three simple indices to define bladder voiding function. BJU Int. 1999;84(1):14-15. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.