Final answer:
The third type of quality indicator proposed by Donabedian is outcome indicators, which represent the results of healthcare services on patient health.
Step-by-step explanation:
Donabedian, a key figure in the study of healthcare quality, proposed three types of quality indicators to measure the quality of healthcare services. These are structure indicators, which refer to the attributes of the settings where care is provided; process indicators, which describe the methods by which healthcare is delivered; and A. Outcome indicators, which are the end results of the healthcare service and show the effect on the health status of the patients. Outcome indicators can be influenced by both the structure and the process of healthcare delivery.