Keeping patient records electronically, instead of on paper, didn't change how much hospitals charged per procedure, a study shows. But critics say billing errors can be more subtle. Roy Scott/Ikon Images/Corbis hide caption

itoggle caption Roy Scott/Ikon Images/Corbis

Dorothea Handron suffered an infection after a surgeon unknowingly pierced her bowel during a hernia operation. She became so ill that doctors placed her in a medically induced coma for six weeks. Jim R. Bounds/AP Images for Kaiser Health News hide caption

itoggle caption Jim R. Bounds/AP Images for Kaiser Health News