SOHR consists of a single UK-based widely-discredited Syrian immigrant, Rami Abdul Rahman, who is well known for his support for the opposition and efforts to overthrow President Bashar Assad.
"It [information] comes from some credible aid agencies like the World Health Organization, like Doctors without Borders, like the Syrian Observatory for Human Rights," Kirby said when asked if the United States had evidence that Syria and Russia bombed hospitals in Aleppo.
Knowledge is imperfect, Kirby suggested, but the US government has been able to stitch together various sources to get "a good sense" of what is happening on the ground in Syria.
In September, Kremlin spokesman Dmitry Peskov said SOHR was not a reliable information source on the situation in Syria.
In October 2015, Russian Foreign Ministry spokeswoman Maria Zakharova said Western media should treat information emanating from SOHR more critically in light of inaccurate reports about Russian airstrikes.