# Bioequivalence and Bioavailability Forum 12:21 CET

## WNL Calculation of partial areas > tlast with BQL= 0 rule [Software]

Hi Babe_Ruth,

» When I set BQL to "no value," then it (blah)
»
» However, when I set BQL to 0, it uses a linear-trapezoidal rule: (Clast + 0)*(T16 - Tlast)
» Nowhere in the documentation does it say that this was the plan.

Do you mean it uses AUCpartial=0.5*(Clast + 0)*(T16 - Tlast) ?

If yes, then this is expected behaviour: Remember that you distinguish between BLQ, missing and a zero.
If you set it to zero then it means you tell WNL to believe that the value is really zero in contrast to not measured. Thus, it was quantifiable so now the last quantifiable value is no longer at t=12 but at t=16. The residual area will naturally also be zero, so the extrapolated area is zero percent. I'd say you are within expectations and specifications.

``` if (3) 4 x=c("Foo", "Bar") b=data.frame(x) typeof(b[,1]) ##aha, integer? b[,1]+1 ##then let me add 1 ```

Best regards,
ElMaestro

"(...) targeted cancer therapies will benefit fewer than 2 percent of the cancer patients they’re aimed at. That reality is often lost on consumers, who are being fed a steady diet of winning anecdotes about miracle cures." New York Times (ed.), June 9, 2018.