Figure 7: Proportional measures of frequency that the search phrases “pain and surgery”, “pain after surgery”, and “anesthesia side effects” were entered by users at the main google search page ( over the time period 2004 – 2010 (x-axis). Each measured time point is expressed as a normalized percentage of the maximum search frequency for all phrases: “pain after surgery”. Web interest in this phrase has steadily increased since 2004. Results are screen shots from the authors’ computer using Google Insights for Search (; accessed: April 30, 2011).