My question is whether my data are a survival analysis problem.
I have 3 groups (2 interventions and 1 control). The 200 patients are all followed up for 6 months only. The follow-up is done by observing the records in a public hospital for any readmissions. I am making the assumption that a patient does not visit any other hospital.
I am interested in the time (in days) to readmission of the patients after their initial discharge. The time of the initial admission was the time they entered the study. The start date is not the same for all individuals – a range of 2 years, more or less.
Basically I have different start times, but the censoring time is the same for all censored patients. It is 180 days for all censored patients.
- Does this affect the survival curve or the comparison between the groups?
- Is there another analysis that I should apply that nbetter matches my data and setting?
When running the Kaplan Meier curve in SPSS, I get a straight line (going down) at the 180 days (x axis). Is this OK?