"The interesting data on co-pays show employees are basically acting as price-sensitive consumers and going for what they perceive as the best value and convenience for the price," says Ania Krasniewska, senior director, CEB. "However, it also sounds a warning that some visits to ER and urgent care facilities should, in fact, be handled at the more cost-effective primary-care level. Not only does this affect cost to the employee in the end, but in large quantities, this significantly affects the cost to the organization."

The price difference between urgent care in-network co-pay and primary care physician co-pay was also found to be minimal at $32 and $17, respectively. As a result, employees might be choosing urgent care facilities simply for convenience since they tend to keep evening and weekend hours and be open holidays.

The price gap between specialists and primary care physicians is also narrowing. From 2010 to 2012 the price differential has dropped from 82 percent to 35 percent higher for specialist visits, according to the study. The closer the two costs get, the more likely employees are to see a specialist for an issue that could have been addressed by their doctor.

Of course, health care situations will always be circumstantial. It would be, after all, hard to tell a mother she can't take her crying child to the ER in the middle of the night because it would be more cost efficient to wait until the clinic is open tomorrow.