John Dee's Almanac

John Dee's Almanac

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John Dee's Almanac
John Dee's Almanac
A Closer Look At The Pfizer Enigma

A Closer Look At The Pfizer Enigma

Using multivariate logistic regression to investigate under-reporting bias

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John Dee
Mar 24, 2022
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John Dee's Almanac
John Dee's Almanac
A Closer Look At The Pfizer Enigma
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In part 4 of my Digging Deeper Into EudraVigilance series we noted an extraordinarily curious result whereby Pfizer jabs were going unlisted as a suspected drug exclusively in the 18 - 64y age group. This morning I decided to run analyses once again but using records for this age group alone.

Pasting another bunch of similar tables didn’t fill me with as much joy this time round so I decided to reach for logistic regression with PfizerZERO as my binary dependent1 and the following as my remaining six independents:

  • Economic Region

  • Primary Source Qualification

  • COVID-19 Diagnosis

  • Concomitant Drug Use

  • Total Drug Entries

  • Total Reactions Recorded

For good measure I also threw in all interactions between these six variables up to the level of 3-way (35 interactions in total), the whole being subject to forward selection using the likelihood ratio. Herewith some stats output to munch through:

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