Valve's flagship multiplayer game has been the most played game in the world at several points of its history, but only on PC. (techradar.com)
At several points of the vetting, committee members could not control their laughter. (citifmonline.com)
The participants had answered survey questions at several points in their teen years, 20s and 30s, and those responses were used to score their symptoms of depression. (articles.chicagotribune.com)