st: Help with multiple baseline data

[Mats Martinell <matsmartinell@gmail.com>]

Dear Statalist,
I'm working on a registry of patients with diabetes. The patients (cases) are included at time of diagnosis, thus almost all cases have different dates (ddmmyyyy) for their first registration. The patients are divided into three groups depending on blood sugar concentration at diagnosis. I would like to graph the mean (with 95% CI) blood sugar concentration for each group over time. My problem is the following:

1. Is there a way I can create a common baseline (day 0) from their date of diagnosis for each case?

2. The follow-up measurements are at differentdates and not at a fixed date from diagnosis. Is there a way to generate a variable for the follow-up measurements ( X days after diagnosis (day 0))?


Best regards,
Mats Martinell
PhD stud
Uppsala university, Sweden




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