IN THE NEWS- Meta-analysis in Nephrology

A recent article in Kidney International reviews the role of meta analysis in Nephrology world. Based on the survey this group did in NYC area, most physicians viewed meta analysis in nephrology useful and influenced their patient care.
What are the limitations of meta analyses?( from the article- refer to article for details)
1. Publication bias
2.Mixing apples and oranges
3. Garbage In, Garbage Out
4. Outcome selection bias
5. Patient exclusion bias
6. Truncated study bias
7. data collection errors
What are the strengths  of meta analyses?
1. Power
2. Highlights areas that need work
3. More transparent form of review- and not just a review article
4. Sounder bias offered
Even with all these meta analyses happening in our literature, many of our guidelines are still "opinion" based.

Ref:
http://www.ncbi.nlm.nih.gov/pubmed/20827259