The finding that lower volume laboratories have increased risk of complications had potentially major implications for referral patterns and third party payers. A third paper based on this same registry found no increase in risk related to the use of combining PTCA with diagnostic catheterization as compared with traditional staged procedures. Again, this finding had important clinical implications. Methodologically, the PTCA papers raised analytical issues related to the multi-center nature of the data. In this example, the benefits of induction therapy are explored for renal allograft patients.
Induction therapy involves the use of powerful anti-rejection agents on a prophylactic basis.
In this analysis, the investigators showed that the beneficial effects of induction therapy on graft survival seem to be limited to a subgroup of patients exhibiting a high level of immune presensitization. There is no benefit to therapy in other patients, thus suggesting that use of these agents could possibly be restricted to the one subgroup of patients. While this result requires validation in an external data set, it demonstrates a potentially enormous strength of meta-analysis in the determination of subgroup effects, and in better determining the target population of therapies, in a manner not possible in individual trials because of their limited sample size.