Drs. Barry Marshall and Robin Warren this week won the Nobel Prize in medicine, which they certainly earned - the hard way.

In fact, if Stockholm's Nobel Prize Committee awarded a prize for perseverance, the Australian researchers should have won that, too.

In the early 1980s, conventional wisdom was that stomach and intestinal ulcers were caused by reckless eating habits and too much stress. Therapy called for healthier diets, including drinking lots of milk, and reducing one's exposure to stressful situations; the worst cases called for surgery.

Then in 1982, Marshall and Warren said their research showed that inflammation of the stomach and related gastric ailments might be aggravated by stress or bad diets, but they weren't the cause of it. Bacteria was. And the best cure wasn't surgery, but antibiotics.

The researchers were ignored until 1985, when Dr. Marshall did something courageous and almost unprecedented. He deliberately ingested a batch of the bacteria that he and Dr. Warren believed were the cause of acute gastric illnesses. They proved their point. Dr. Marshall's stomach became inflamed, and for weeks he was as sick as a dog.

It still took nearly a decade for the medical community to accept their ulcer research and therapy as the new conventional wisdom.

Courage manifests in many forms. The Nobel panel's recognition this week of the Australian researchers' courage and their contribution to medicine was well-earned and overdue.