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Open Systems Pharmacology - Live Documentation
https://docs.open-systems-pharmacology.org/
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Issues regarding the table formulation implementation/documentation #90

Open SRuedesh opened 5 years ago

SRuedesh commented 5 years ago

Dear OSPS community,

I stumbled upon an issue regarding the table formulation for tablet dissolution. The OSPS documentation states that

The origin (0, 0) is always present.

which lead me to the conclusion, that there would be no difference, whether or not I specified 0, 0 within the table. However, while testing out different dissolution profiles I discovered, that not specifying 0, 0 led to interesting results:

image The dashed lines represent the fraction dissolved and the solid lines represent the corresponding plasma concentration-time profile. The simulations are identical, apart from the table formulation. To illustrate the issue I created minimal (hypothetical) dissolution profiles.

Table formulation "blue simulation":

Time [h] Fraction (dose)
0 0
1 0.1
9 0.9

Table formulation "red simulation":

Time [h] Fraction (dose)
1 0.1
9 0.9
  1. The dissolution for the "red simulation" apparently starts at 1h which makes

The origin (0, 0) is always present.

all the more confusing. In case this is the intended behaviour, something along the lines of

The origin (0, 0) should be specified.

probably makes more sense.

  1. In the "red simulation" 10% of the dose disappear, which (for me) is not the expected behaviour. I wonder if it was intended upon implementation and what the rationale was. Certainly, it can lead to confusion and potential errors during model development. If, however, this is the intended behaviour, the documentation should clearly state that to avoid confusion and errors.
msevestre commented 5 years ago

Hey @sruedesh Thanks for pointing that out. I'll have to investigate a bit and will get back to you shortly. It could be that the documention is outdated. In that case, you could even propose a change ;-)

I'll let you know

msevestre commented 4 years ago

@SRuedesh So I double-checked the code I think the documentation is indeed misleading

What is meant is: (0,0) is present by default

As you can see, if I create a NEW table formulation, it automatically looks like so

image

with a (0,0) point added automatically. Why would you want to remove the first (0, 0) point? Maybe to simulate some kind of delay in the dissolution function ? (@Yuri05 would that be correct?)

Please feel free to suggest an improvement in the documentation. Here is how :)

https://docs.open-systems-pharmacology.org/how-to-contribute

Hope that helps, Michael