A Closer Look At The Pfizer Enigma
Using multivariate logistic regression to investigate under-reporting bias
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: