The actual findings (and a lesson on half-truths!):
Now, let’s analyze the data.
Fox isn’t last on the list, although it’s close -- 35 percent of Fox viewers earned a high knowledge rating, which was tied with local television news and was one point ahead of the network morning shows.
However, Fox’s 35 percent score places it exactly at the national average. This seems paradoxical -- Fox ranks near the bottom of a long list of media outlets, yet it sits right at the national average. But there’s an explanation. Lots of respondents reported following none of the media outlets they were asked about, and those respondents did quite poorly on the knowledge quiz -- not surprisingly. That meant that the non-media-using respondents brought down the national average, but they didn’t constitute a separate category that ranked lower than Fox on Pew’s chart.
Since Stewart was referring to "media viewers," this doesn’t undercut his point. However, the data includes an important counterpoint to Stewart’s claim: Viewers of at least one show on Fox scored quite well -- The O’Reilly Factor, of whom 51 percent made it into the high knowledge group. That made it equal to National Public Radio -- a longtime target of conservative complaints about liberal media bias -- and only three percentage points behind Stewart’s own show, at 54 percent.
• "Misperceptions, The Media and The Iraq War" study, 2003. This study focused on the Iraq War and the lead-up to it. It asked three questions: "Is it your impression that the U.S. has or has not found clear evidence in Iraq that Saddam Hussein was working closely with the al-Qaida terrorist organization?" "Since the war with Iraq ended, is it your impression that the US has or has not found Iraqi weapons of mass destruction?" And whether, "The majority of people favor the US having gone to war."
On these questions, Fox clearly did the worst among the major news outlets. The "misperception rate" for Fox was 45 percent. The highest for other news outlets was CBS News at 36 percent; those with lower "misperception rates" included CNN, ABC, NBC, the print media and NPR/PBS, which was lowest at 11 percent.
This study is probably the strongest support we found for Stewart’s claim, in part because the difference between Fox and the other news outlets was so stark, and in part because the questions asked have pretty clear-cut "right" and "wrong" answers.
There's lots more that you can read on the PolitFact wwebsite. I guess Rylie's point must be, "yes, Fox is bad - but they're not the worst!" ;)