Are California hospitals doing a better job of preventing serious mistakes in the wake of a state program that issues high-profile penalties for such errors? One reporter finds reasons for doubt in the data.

In 2012, a surgical team mistakenly removed Paul Kibbett’s healthy left kidney rather than the cancerous tumor on the right side. Since then, the hospital has worked to build a culture where reporting mistakes is celebrated.

This report was produced as a project for the 2015 California Data Fellowship, a program of the Center for Health Journalism at the USC Annenberg School for Communication and Journalism.
Other stories in the series include:
Sharpening the focus on medical errors
Do penalties reduce medical errors?