If patients are mad, unhappy or just plain not satisfied with how they were treated by their doctor or hospital, a big Pennsylvania health system has just updated a mobile app that gives them at least some of their money back.

Geisinger Health System, which provides care to more than 2.6 million people in 44 counties in Pennsylvania, has just updated one of its most popular consumer digital healthcare programs—a mobile app and customer service program that gives patients some money back if they are unhappy with a recent hospital stay or office visit. Launched in November 2015, Geisinger’s ProvenExperience app for Android or Apple devices lets a consumer rate a hospital stay or office visit.

The new version of the app features nine screens that asks users to detail their complaints. For example, it offers a drop-down menu to determine if the cause of a complaint was administrative, related to a doctor or nurse, or if a recent episode of care “didn’t reduce or adequately adjust my pain.” Another series of screens lets patients request a refund and explain why they are asking for one.

Geisinger launched the app in late 2015 as a way to bring more retail-like customer service to healthcare. “The way I see it, if you go into Starbucks and you’re not happy with your order, they don’t sip your latte and argue that they made it correctly. They just take care of you on the spot,” says Geisinger CEO David Feinberg . “What matters to me is that every patient is satisfied with their treatment, and so I started thinking, ‘What is our guarantee? What is our refund?’ We need to be disruptive to move the practice of providing great patient experience forward and so the decision was made to give unsatisfied patients their money back.”

Patients that use the ProvenExperience app aren’t given a full refund for an expensive hospital stay. However, if a spine surgery patient paid a $1,000 co-pay and she wasn’t pleased with how office staff treated her, she can log into the app and select from a sliding scale how much of the co-pay she wants refunded. She can choose from $1 to $1,000 and the refund request is processed within 3 to 5 business days. The exact amount of a refund is determined after the health system reviews each complaint. The program is popular—and taught Geisinger some valuable lessons about how to improve patient satisfaction. Since the program was launched, about 1,800 complaints have been received and resolved, and about $500,000 in refunds have been paid—an average of $546 for each situation that Geisinger determines merits a refund.

The $500,000 given in patient refunds from ProvenExperience amounts to less than one-half of one percent of the health system’s annual revenue of about $11.56 billion. The payoff, Geisinger executives say, is in learning more about how patients feel about their treatment.

Since the launch of ProvenExperience the health system has seen a 23% increase in direct messages related to episodes of care from patients and patient advocates, such as a family member with power of attorney. “Now we know even more what’s wrong because patients tell us what we need to fix,” says Chanin Wendling, director of Geisinger in Motion, a digital and mobile health program.

Feedback from ProvenExperience has helped Geisinger put more customer service features into a new website design that it will launch next month. The new site will include simplified screens and better site search to help patients find doctors, access their health information and research care. Based on feedback from PatientExperience Geisinger also has hired a full-time employee to address patent concerns brought directly to the CEO’s office.

“In the beginning, I talked to other health system CEOs and industry leaders about ProvenExperience and they all said, ‘Don’t do it.’ I really felt dejected,” Feinberg says. “Then I thought about Kodak executives discussing digital photography. And Blockbuster talking about online video options. Were they also told, ‘Don’t do it?’ That’s when I said to myself, ‘We’re doing it.’”

Geisinger is comprised of 30,000 employees, including nearly 1,600 employed physicians, 12 hospital campuses, two research centers and a 510,000-member health plan.