Final class of evidence (CoE)-treatment	Yes
Study design:
Prospective cohort
Retrospective cohort	•
Case control
Case series
Methods
Patients at similar point in course of treatment	•
Follow-up ≥85%	•
Similarity of treatment protocols for patient groups	•
Patients followed-up long enough for outcomes to occur	•
Control for extraneous risk factors	•
Overall class of evidence	II
The definiton of the different classes of evidence is available on page 59.