This recommendation defines a procedure for conducting behavioral studies targeted at investigating video streaming performance and its relation to users' Quality of Experience. The studies are to be conducted in controlled environments. Subjects are exposed to different initial loading delay conditions and other quality degradations typical for video streaming, and may be asked to rate audiovisual quality or their experience. Additionally, their behavior as a response to long loading times (i.e. aborting the video playback during its loading phase) may be investigated.