Say you work at US News that attempts to rank everything under the sun. You got an English degree from State U. Your supervisor says you are in charge of objectively ranking the best colleges for psychiatry this year and providing an article on it. You Google “psychiatry” to find out that it isn’t a college major. There isn’t a comprehensive source for residency information that discloses step scores or even lists who the residents are. There isn’t a ranking for best psychiatrists to see what programs they went too or teach at.
You need some criteria though because you don’t want to disappoint your boss who has a philosophy degree. You research the amount of grants the mental health or psychology department received. You can determine the number of publications. You could take the undergraduate “prestige” scores and give that some weight because good schools do good things right? Psychiatry is like psychology, so maybe average GRE scores could be helpful if you can find those? Many research projects require more than 1 department, so total research dollars could work as a factor. Psychiatry is sometimes in hospitals, and another entry-level journalist developed a best hospitals ranking already. Let’s give that some weight. You can’t have a best training program at terribly ranked hospitals right?
US News doesn’t have the funds to fly a journalist to each of the 100+ psychiatry programs to gather data and interview faculty. Faculty don’t have time to complete surveys for every ranking system in the USA or do interviews with every ranking magazine.
The criteria to rank psychiatry training or psychiatry departments doesn’t include checking to see if they have one.