MedStat Stutter

Phantasies of a physicist fallen among physicians

Excel eignet sich nur eíngeschränkt zur statistischen Auswertung klinischer Studien, aber zu Dateneingabe und Verwaltung bei medizinischen Studienarbeiten ist es durchaus geeignet. Hier einige Rezepte, von Muss sein bis Das Beste zum Schluss.

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You can find quite a few post describing on the best way to access an SQLite database from Excel, for example on Stack overflow. Often, the method uses VBA, or some older version of Excel, and I could not get things to work with my settings:

  • Windows 10, 64 bit
  • Virus Norton 360 premier
  • Office...

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Tabelle für den Vorzeichentest

Politiker oder Banker werden manchmal gefragt, wieviel ein Brötchen koste. Wenn dann Beträge wie "10 Cent" genannt werden, soll das anzeigen, wie weit der oder die Gefragte von der Lebenwirklichkeit entfernt ist.

So erging es mir neulich in einem Seminar. Vorgestel...

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A colleague asked me how to present the results of a study in gastric emptying. As you have seen multiple time here, the emptying time t50 is the target variable. But read on even if you work with blood pressure (also often misused as example), rehabilitation, or pharmacology. The methods are the sa...

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Summary

Using vectors for indexed access to ragged arrays in Stan

volume ~ normal(
      v0[record] .* (1+ kappa[record] .* (minute ./ tempt[record])) .*
      exp(-minute ./ tempt[record]), sigma);

Fitting gastric emptying time series

Gastric volume times serie measured by MRI techniques can have an initial volume overshoot due to secretion. To estimate half-times and the degree of overshoot, the author of this blog has introduced the linexp function [@Fruehauf2011] with three parameters to complement the power exponential function used in earlier research [@Elashoff1982, @Elashoff1983b] with scintigraphic data.

linexp:

v = v0* (1+t*kappa/tempt)*exp(-t/t_{empt})

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