"The media outlets that New America relies upon are the three major international wire services (Associated Press, Reuters, Agence France Presse), the leading Pakistani newspapers (Dawn, Express Times, The News, The Daily Times), leading South Asian and Middle Eastern TV networks (Geo TV and Al Jazeera), and Western media outlets with extensive reporting capabilities in Pakistan (CNN, New York Times, Washington Post, LA Times, BBC, The Guardian, Telegraph)."
Yes, that's right. They draw from a wide range of major international and regional news reports. What more reliable source would you suggest?
Unfortunately that's necessary when you're attempting to condense a large quantity of news reports from different languages into 3 columns of numbers. Their algorithms for interpreting the reports are completely open to the public. Their assumptions sound reasonable. Is it perfect? Of course not. But in the real world we don't get perfect information. You'd be hard pressed to find a more thorough and reliable study on drone casualties in AfPak.
Of course you're not. You're convinced that our drone attacks are wantonly killing scores of innocent civilians and no amount of conflicting information will convince you otherwise. I challenge you to provide the data that has informed this assumption of yours.