Fig. 2.

Bar chart showing the surgeon responses to the question ‘Do you believe femoroacetabular impingement (FAI) is a cause of osteoarthritis?’ The responses of surgeons who routinely perform FAI surgery are represented in blue, and those who do not are in red. The three digits of the surgical equipoise ratio (SER) represent the sum of the scores within the range ‘-5 to -1’, followed by scores of ‘0’, followed by scores within the range ‘+1 to +5’.