Physicians have always checked their patients' physical health before surgeries. Increasingly, they're also checking on patients' mental health to ensure good outcomes.

A new book by University of Pennsylvania psychologist David Sarwer emphasizes the importance of the screening.

The psychological assessments get to the same question physical health checks address: Is the patient healthy enough to go forward with surgery?

The checks are routine before bariatric surgeries and organ transplants to make sure a patient is ready for life after surgery, he says.

"Patients are going to have to make these lifestyle changes for the rest of their lives," he said. "If they are not compliant with the diet or the use of medications, they run the risk of compromising their long-term outcomes."

Checking patients' emotional health is also becoming more common in other fields, such as spine surgeries or OB-GYN procedures, Sarwer says. With rising health-care costs, there's more pressure to focus on outcomes.

"To make sure that when we're making the tens of thousands of dollars of an investment in a surgical procedure, that patients are really in the best position to have the best outcomes," explains Sarwer, a clinical psychologist at the Perelman School of Medicine at Penn.

Together with Andrew Block, Sarwer has edited "Presurgical Psychological Screening: Understanding Patients, Improving Outcomes," published by the American Psychological Association.

He says the book outlines the importance of psychological screens in different areas of surgery. The tests also address patients' expectations for the surgery to make sure they are not disappointed with the results, he said.