PeterDisAbelard. said...
Njs,
Not sure what to make of this statement in your study: "Of 1,111 men who fulfilled the D'Amico low risk criteria, those with a surgical delay of 6 months or more were significantly older, had a higher proportion of African American men, and a lower proportion of clinical stage T2a (vs T1). It seems like a lot to try to control for. That's often a problem with retrospective studies.
I think the point is that age, race and T1 stage are likely causal factors for delaying surgery. Clinical stage was apparently controlled for in terms of time to biochemical recurrence:
"On multivariate analysis with prostate specific antigen and clinical stage, surgical delays of 6 months or more were significantly and independently associated with time to biochemical progression."But it does not mention trying to control for age or race, so I agree that is a potential weakness (e.g. if older men or black men are more likely to have higher Gleason grade disease).