Dr. Margaret Billingham, a Stanford University pathologist who developed criteria by which surgeons could tell if a transplanted heart was thriving or being rejected, died of kidney cancer July 14 at Sierra Nevada Memorial Hospital in Grass Valley, Calif. She was 78.

"Her contributions were the key to advancing the care and survival of heart transplant patients," said Dr. Robert Robbins, director of the Stanford Cardiovascular Institute.

Billingham joined Stanford in 1966, two years before Dr. Norman Shumway performed the first successful heart transplant in the United States there. To ensure the success of the transplants, it was vital to know if the body was accepting or rejecting them. Billingham and Dr. Philip Caves devised a technique to remove tiny snippets of heart tissue and analyze them for rejection.

She developed a standardized scale for interpreting such biopsy results that is still used in modified form: the Billingham Scheme, also known as Billingham's criteria. She not only created it, but she persuaded the international community to adopt a similar scale, said Dr. Sharon Hunt, a professor of cardiovascular medicine.

Billingham joined Stanford at a time when female physicians were a rarity at academic institutions. She was a fierce advocate for women and toward the end of her career was appointed director of women in medicine and medical sciences at Stanford. In 1990, she became the first female president of the International Society for Heart and Lung Transplantation.

She was born Margaret E. Macpherson on Sept. 20, 1930, in Tanga, Tanzania, where her father worked for the British government. She earned her medical degree in 1954 at Royal Free Hospital School of Medicine in London. She met her husband, Dr. John Billingham, while both were interning in London, and they were married in 1956. The family emigrated to the United States in 1963.

Billingham retired from Stanford in 1994.

In addition to her husband, former chief of the life sciences division at NASA Ames Research Center, she is survived by two sons, Robert and Graham, both of Auburn, Calif.; a sister, Shirley Ann; and four grandchildren.

thomas.maugh@latimes.com