10 Things We Don't Know About Looming Readmission Penalties

Here are the most pressing issues hospital leaders hope CMS will answer soon:

1. How will hospitals be compared?
Hospitals with greater than expected risk adjusted readmission rates between July 1, 2008 and June 30, 2011 will be penalized in the first round.

But what groups of hospitals would constitute a fair comparison? Or those within a similar region or state or similar size? Or those with similar patient populations such as safety net or rural hospitals? Or will each hospital be measured with all others across the country?

This is important because there are vast regional differences in readmission rates across the country, according to CMS's Medicare Hospital Quality Chartbook for 2011.

CMS has indicated it intends to compare every hospital's readmission rates with the rest of the nation's, but some hospital officials hope for reconsideration.