RESULTS The instruments most frequently used were single-item VAS and Biberoglu and Behrman pain score , while multidimensional inventories were used in few studies .
The results of clinical studies in CPP are more frequently based on one-dimensional measurements .
RATIONALE Many types of  pain assessment are available to research ers carrying out clinical trials in chronic pelvic pain ( CPP ) , ranging from a single-item scale to multidimensional inventories .
AIM Our objective was to investigate which assessment s of pain are more commonly used in clinical trials on CPP .
Laparoscopic excision of endometriosis: a randomized, placebo-controlled trial.
OBJECTIVE To examine the effect on pain and quality of life for women with all stages of endometriosis undergoing laparoscopic surgery  compared with placebo surgery . DESIGN A r and omized , blinded , crossover study . SETTING A tertiary referral unit in a district general hospital . PATIENT(S ) Thirty-nine women with histologically proven endometriosis completed the 12-month study . INTERVENTION(S ) Women were r and omized to receive initially either a diagnostic procedure ( the delayed surgical group ) or full excisional surgery ( the immediate surgery group ) . After 6 months , repeat laparoscopy was performed , with removal of any pathology present . MAIN OUTCOME MEASURE(S ) The end points were changes from baseline values of visual analogue pain scores , vali date d quality -of-life instruments ( EQ-5D and SF-12 ) , and sexual activity question naire scores . Patients and assessors of outcomes were blinded to the treatment-group assignment . RESULT ( S ) Significantly more of the 39 women operated on according to protocol reported symptomatic improvement after excisional surgery than after placebo : 16 of 20 ( 80 % ) vs. 6 of 19 ( 32 % ) ; chi(2)(1 ) = 9.3 . Other aspects of quality of life were also significantly improved 6 months after excisional surgery but not after placebo .  Progression of disease at second surgery was demonstrated for women having only an initial diagnostic procedure in 45 % of cases , with disease remaining static in 33 % and improving in 22 % of cases . Nonresponsiveness to surgery was reported in 20 % of cases . CONCLUSION ( S ) Laparoscopic excision of endometriosis is more effective than placebo at reducing pain and improving quality of life . Surgery is associated with a 30 % placebo response rate that is not dependent on severity of disease . Approximately 20 % of women do not report an improvement after surgery for endometriosis
RESULTS The instruments most frequently used were single-item VAS and Biberoglu and Behrman pain score , while multidimensional inventories were used in few studies .
The results of clinical studies in CPP are more frequently based on one-dimensional measurements .
RATIONALE Many types of  pain assessment are available to research ers carrying out clinical trials in chronic pelvic pain ( CPP ) , ranging from a single-item scale to multidimensional inventories .
AIM Our objective was to investigate which assessment s of pain are more commonly used in clinical trials on CPP .