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 .
Botulinum Toxin Type A for Chronic Pain and Pelvic Floor Spasm in Women: A Randomized Controlled Trial
OBJECTIVE : To estimate whether botulinum toxin type A is more effective than placebo at reducing pain and pelvic floor pressure in women with chronic pelvic pain and pelvic floor muscle spasm . METHODS : This study was a double-blinded , r and omized , placebo-controlled trial . All participants presented with chronic pelvic pain of more than 2 years duration and evidence of pelvic floor muscle spasm . Thirty women had 80 units of botulinum toxin type A injected into the pelvic floor muscles , and 30 women received saline .  Dysmenorrhea , dyspareunia , dyschezia , and nonmenstrual pelvic pain were assessed by visual analog scale ( VAS ) at baseline and then monthly for 6 months . Pelvic floor pressures were measured by vaginal manometry . RESULTS : There was significant change from baseline in the botulinum toxin type A group for dyspareunia ( VAS score 66 versus 12 ; χ2=25.78 , P<.001 ) and nonmenstrual pelvic pain ( VAS score 51 versus 22 ; χ2=16.98 , P=.009 ) . In the placebo group only dyspareunia was significantly reduced from baseline ( 64 versus 27 ; χ2=2.98 , P=.043 ) . There was a significant reduction in pelvic floor pressure ( centimeters of H2O ) in the botulinum toxin type A group from baseline ( 49 versus 32 ; χ2=39.53 , P<.001 ) , with the placebo group also having lower pelvic floor muscle pressures ( 44 versus 39 ; χ2=19.85 , P=.003 ) . CONCLUSION : Objective reduction of pelvic floor spasm reduces some types of pelvic pain . Botulinum toxin type A reduces pressure in the pelvic floor muscles more than placebo . Botulinum toxin type A may be a useful agent in women with pelvic floor muscle spasm and chronic pelvic pain who do not respond to conservative physical therapy . Clinical Trial Registration : Australian Clinical Trials Registry , http://www.actr.org.au/ , ACTRN012605000515695 LEVEL OF EVIDENCE :
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 .