Patients often leave the doctor's office with careful instructions about what to do if their illness doesn't get better – or if it gets worse. They are given instructions to "call or return to the office if …"

These instructions often are difficult to follow and leave much to be interpreted by the patient. Sometimes they require difficult judgments. For example, is it worth going back to the emergency department again – and waiting 15 hours – if I think the rash is getting worse? What if the medicine just hasn't started to work?

Sometimes the doctor's instructions are unclear, ambiguous or overly technical so that the patient doesn't exactly understand. Other times, patients forget an instruction or decide not to follow the doctor's advice – often because it involves an inconvenience, an expense or a disagreement with the medical advice.

Other patients are embarrassed to come back to the doctor because they fear they may have misunderstood the doctor or may be annoying or bothering him or her. Then when things get worse, they are angry.

Dr. David Shapiro, a Palo Alto doctor and lawyer, described to me a recent case in which a 17-year-old boy developed abdominal pain and vomiting. His mother brought him to the ER, and an exam and urine test came up normal. The doctor gave him some medicine to stop the vomiting and sent him home with printed instructions that told him, among other things, to return to the ER if the pain got worse. The instructions also told him to go see his primary care doctor in two to three days.

But over the next week, the young man felt better; he had no more pain, fever or chills. While he slept more than usual and still had some pain, he did get up and go to school. On the eighth day, he again felt sick and his mother took him to her usual doctor. The doctor sent him to the emergency room, where he was diagnosed with an infected appendix that required a weeklong hospitalization. He did fine and recovered completely.

The story doesn't end here. The family sued all the doctors involved in the young man's care for missing the diagnosis and for pain and suffering. The family's lawyers argued that the discharge instructions from the emergency room were overly long and confusing. Further, the instructions said to return to the emergency room if the pain worsened, which it never did.

The instructions did not address what to do if the pain didn't worsen but remained the same or slightly improved. It was under these conditions that the infection became life-threatening. The doctor's lawyer said the family never saw their primary care doctor in two to three days as they were clearly told.

In this case, the jury found 10-2 in favor of the doctor. They blamed the mother for not bringing her son back to the doctor sooner. However, there are two larger problems. The first was that the boy first visited the hospital at a time when no one could have made an accurate diagnosis, even with the help of blood tests and scans. Sending the person home with follow-up was reasonable.

The second problem was unclear communication: instructions that were long and left responsibility to the family to arrange for follow-up. In an ideal health care system, this young man would have been given both a specific follow-up appointment – with a doctor at a specific time and place – and a telephone number to call if he had questions.

As long as we are talking about ideal systems, it might have been nice if the doctor or a nurse called a day or two later to check in and see how the teen was doing. Communication is a vital issue in health care, and with computers, cell phones and the Web, we ought to be able to take giant steps forward to promote better health.

Michael Wilkes, M.D., is a professor of medicine at the University of California, Davis. Reach him at drwilkes@sacbee.com.