The 2008 Draft FDA guidance on the ISE provided in this session provides a lot of detail on pooled analyses (also referred to in the guidance as “meta-analyses”). Based on the information in this guidance, what are the benefits of pooling efficacy data across studies? What might be some of the inherent problems in pooling data (including factors that would prevent pooling)?
Student #1 – Cheryl
1. According to the 2008 draft guidance “Integrated Summary of Effectiveness”, there are several benefits to pooling the data. One benefit to pooling data is when individual studies are expected to lack power when analyzing patient subgroups such as demographics or geographical regions. Another benefit is when looking at the dose response relationship. This would be helpful when the various studies used different dose levels. The third benefit identified in the 2008 draft guidance is when looking at the drug effect on secondary endpoints.
2. One of the biggest problems with pooling data is that it is often not thought about until after analysis is complete and the potential for bias enters the equation. It is better to prepare for pooling when the protocol is written. Decisions on how the data should be analyzed should be decided at this point to avoid any bias. The 2008 draft guidance notes that in the case of studies with “drastic heterogeneity”, pooling is not suggested.