The number of urgent care centers affiliated with hospitals is on the rise. Overcrowded emergency rooms and electronic health records are part of the reason.

First, urgent care centers started to pop up everywhere.

They still are, but now more of them are part of larger hospital systems.

The Urgent Care Association of America (UCAOA) reports there are 7,100 full-service urgent care centers in the country.

About 22 percent are owned by hospitals, 15 percent are part of joint ventures with a hospital system, and 19 percent are corporate-owned entities, according to a UCAOA report.

The number of centers is expected to keep rising. Another report says that the urgent care industry will grow 5.8 percent each year through 2018.

A 2010 Health Affairs study found that 13 to 27 percent of all emergency department visits could take place at an urgent care center or a retail clinic. That produces an estimated cost savings of about $4.4 billion in the United States each year.

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Steve Sellars, who will take over as president of the UCAOA next month, said hospitals see many benefits to offering urgent care as a way to fill the need between emergency care and primary care.

“Urgent care can improve access to care and help alleviate emergency department overcrowding, particularly when overwhelmed by patients with low acuity conditions who have no other on-demand medical option,” Sellars told Healthline.

He said many hospitals are getting into the business of urgent care because it allows patients who need follow-up care to see a specialist in the health system.

“Overall, we are seeing increased interest by hospitals in urgent care centers, either joining with others to develop urgent care platforms as part of integrated health systems, or by acquiring urgent care centers as part of their outpatient ambulatory networks,” Sellars said. “We expect both of these trends to continue.”

Rick Watson, director of outpatient market development for Aria Health in Pennsylvania, said urgent care centers are helping doctors, too.

They eliminate nonemergent cases from emergency rooms, leaving ER doctors free to focus on critical cases, Watson told Healthline.

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Dr. Lawrence Friedman, a primary care physician and associate dean of clinical affairs at UC San Diego Health, said his institution is opening up its first urgent care center in La Jolla, California.

Patients seen there will be able to have any records in the UC San Diego Health system accessed during their urgent care visit.

“The decision to open an urgent care was driven by what our patients needed and wanted — convenience,” Friedman told Healthline.

He said the healthcare system wanted to ensure that patients could get access to high-level care knowing that emergency rooms across the nation continue to face overcrowding issues.

An urgent care center tied to the larger system will improve the patient experience, Friedman added.

“I think patients have a level of confidence in urgent care facilities associated with hospital systems versus nonaffiliated urgent care facilities,” Watson added.

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Tom Charland, chief executive of the consulting firm Merchant Medicine, recently told the Wall Street Journal that patients over 50 like urgent care centers connected to a larger system so their visits can go into their medical records already with the hospital system.

Many urgent care centers not linked with hospitals offer patients the ability to forward visit details to their primary care doctors or other physicians.

Watson said there’s another benefit to choosing hospital-affiliated centers.

“Medicare patients are more likely to receive treatment at a hospital-affiliated urgent care center because their insurance will likely be accepted. You are likely to find that nonaffiliated urgent care centers may not accept Medicare,” Watson added.

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Dr. David J. Mathison, a pediatric emergency physician with PM Pediatrics, which runs several urgent care centers throughout the country, said that hospitals are late to the urgent care game.

Hospital-based urgent care facilities count on brand recognition to attract customers. That can be effective for consumers new to urgent care who seek brand familiarity, he said.

“However, hospitals generally specialize in intensive care, surgical procedures, and complex diagnostic testing, and may not meet the routine needs of the outpatient community where customer service, care quality, and efficiency are paramount,” Mathison told Healthline.

In the 2014 fiscal year, urgent care centers reported about 14,000 patient care visits. They handle four visits per hour, on average, and about 50 visits per day.

Also, 66 percent of patients have an outside primary care physician, the UCAOA reports.