New Delhi, July 3 -- For the roughly 100,000 Americans who begin dialysis each year, a kidney transplant is more than a better treatment. It is the only one that can fully reverse what kidney failure takes. It extends life, on average, by more than a decade, and it frees patients from the machines that substitute, imperfectly, for what two failing organs once did without thought. The path to getting one starts with a referral. A large new study found that for nearly half of all referred patients, that is also where the path ends.

48 percent of referred patients never initiated their evaluation, and only 19 percent completed the process and reached the transplant waitlist. What separated those who advanced from those who disappeared was n...