Hospitals are trying to make scheduling appointments and getting test results as simple as booking flights for an out-of-town trip.

At West Penn Allegheny Health System, which includes Allegheny General and Western Pennsylvania hospitals, patients now can choose a time for mammograms and bone density screening by getting online, even at midnight on a Saturday, and making a request. And a few University of Pittsburgh Medical Center physician practices allow patients to make doctor appointments online.

"You're doing it at your convenience," said Nick Valadja, West Penn-Allegheny vice president and chief information officer. "You're not locked into certain business hours that may be inconvenient."

The West Penn-Allegheny's service, called ScheduleConnect, has been up and running for about a month, he said. Since then, more than 60 people have used it to make their appointments.

Patients click on the Schedule-Connect link on the hospital's Web page, fill out some basic information, choose a site to have the test and check boxes to indicate what time they'd like the appointment.

A scheduler calls or e-mails back to verify it. Patients will still need a doctor's prescription to get the tests done.

Measures like the ones used to protect data when making online credit card purchases ensure privacy and security, Mr. Valadja said.

The idea for the service grew out of discussions that began about a year ago, said Jim Rosenberg, the health system's executive vice president of hospital operations.

Someone noted that "you can go online and you can get yourself a boarding pass, but our patients can't go online and get access to our services," he said. "Why are we trailing the airline industry?"

Mammography and bone densitometry scheduling are the first of what could be a broad range of patient services to be offered online. Health system officials are examining the possibility of letting patients schedule other tests and renew prescriptions through a Web site.

Eventually, patients will probably be able to go online to make appointments with their doctors, Mr. Rosenberg said.

In a handful of UPMC physician practices, people are doing just that, said Dr. Dan Martich, vice president of eRecord, UPMC's electronic health record program.

The service is accessible to patients who have seen the doctor and want to make follow-up appointments or get test results online.

"They are given the opportunity to sign up and they're given at that point a user name and a password," Dr. Martich explained. Doctors and patients may exchange e-mails, but they are messages sent through the secure site, not conventional Yahoo or Hotmail accounts.

At first, some patients overwhelmed their physicians by sending notes through the system. Now, as people have become used to it, the e-mails are mostly about getting prescriptions renewed, he said.

The doctors, who might otherwise have to return 50 phone calls, find the system to be convenient for them, too.

"This has reduced some of those phone calls that they have to return at the end of the day," Dr. Martich said.

He sees great potential for more online medical services, in part because tracking appointments, tests and results might help patients see how their health care dollar is spent.

"My hope is it becomes unbelievably widespread," he said. "We are likely to see patients who are more attuned to their health care."

But people who are not familiar or comfortable with computers and the Internet shouldn't worry about being left behind, Mr. Valadja said.

"You're still going to have the option to call the scheduling office," he said.