“…Previous studies relevant to this area have been constrained by research designs that are merely anecdotal (Ercolani et al, 1983;Markel, Rigberg, & Strausz, 1983) or retrospective open clinical trials (Gross et al, 1980(Gross et al, /1981Rosenthal et al, 1984). In investigations employing control groups, it is typical to compare CPP patients to non-pain outpatients attending a gynecological clinic (Hodgkiss & Watson, 1994;Lorençatto et al, 2006;Magni et al, 1986;Rosenthal et al, 1984;Walker et al, 1988;Waller & Shaw, 1995).…”