The researchers say elderly patients are undertriaged -- with only 17.8 percent being taken to a designated trauma center -- compared to 49.9 percent of younger patients. The study, published in the Archives of Surgery, also finds the decrease in transports starts at age 50, with another decrease noted at age 70.

The study researchers -- led by David C. Chang of Johns Hopkins School of Medicine and Johns Hopkins Bloomberg School of Public Health in Baltimore -- analyzed 10 years of data from the statewide Maryland Ambulance Information System and interviewed 159 emergency medical personnel.

One quarter of those interviewed cited inadequate training for managing elderly patients as the reason for not taking more elderly to trauma centers, but 13 percent said it could be age bias.

The researchers suggest retraining providers about triage protocols.

"Additionally, it may be helpful to highlight the literature that now suggests that elderly trauma patients do, in fact, return to productive lives after their injury, which can eliminate the perception of futility of care that may be used consciously or subconsciously to justify age bias," the study authors said in a statement.