Waiting has long been part of medicine. Patients like Ms. Odlum wait for test results; others spend weeks or months waiting for appointments or stranded for hours in doctors' waiting rooms.

But health care researchers say the waiting problem has only gotten worse. Advances in technology have created more tests and procedures to wait for, and new drugs and treatments mean more people need more doctor visits. Doctors' appointments for people over 45 increased by more than 20 percent in the last decade, according to the National Center for Health Statistics. Emergency room visits increased by 23 percent, although the number of hospitals declined by 15 percent.

Some doctors say they doublebook appointments to make up for patient cancellations. And doctors say they are pulled in so many directions that, in many cases, long waits are unavoidable.

"There is nothing magic about waiting," said Dr. Charles K. Francis, president of the American College of Physicians.

"Most of us have patients in the hospital and patients in the office," Dr. Francis said. "Then the patient has to go to the lab, and medicine is unpredictable."

He added that insurance companies reimbursed doctors at lower rates than in the past, resulting in intense pressure to see large numbers of patients. "You have to work long hours and see more patients just to keep your office open," he said.

Recently, however, patients, some doctors and researchers have begun to ask why medicine cannot be as accountable to its customers as any other business. And some doctors' offices and hospitals are starting to solve their waiting problems by applying techniques that businesses use.