PMID- 21106059
OWN - NLM
STAT- MEDLINE
DCOM- 20130214
LR  - 20231105
IS  - 1477-7525 (Electronic)
IS  - 1477-7525 (Linking)
VI  - 8
DP  - 2010 Nov 24
TI  - Defining a minimal clinically important difference for endometriosis-associated 
      pelvic pain measured on a visual analog scale: analyses of two 
      placebo-controlled, randomized trials.
PG  - 138
LID - 10.1186/1477-7525-8-138 [doi]
AB  - BACKGROUND: When comparing active treatments, a non-inferiority (or one-sided 
      equivalence) study design is often used. This design requires the definition of a 
      non-inferiority margin, the threshold value of clinical relevance. In recent 
      studies, a non-inferiority margin of 15 mm has been used for the change in 
      endometriosis-associated pelvic pain (EAPP) on a visual analog scale (VAS). 
      However, this value was derived from other chronic painful conditions and its 
      validation in EAPP was lacking. METHODS: Data were analyzed from two 
      placebo-controlled studies of active treatments in endometriosis, including 281 
      patients with laparoscopically-confirmed endometriosis and moderate-to-severe 
      EAPP. Patients recorded EAPP on a VAS at baseline and the end of treatment. 
      Patients also assessed their satisfaction with treatment on a modified Clinical 
      Global Impression scale. Changes in VAS score were compared with patients' 
      self-assessments to derive an empirically validated non-inferiority margin. This 
      anchor-based value was compared to a non-inferiority margin derived using the 
      conventional half standard deviation rule for minimal clinically important 
      difference (MCID) in patient-reported outcomes. RESULTS: Anchor-based and 
      distribution-based MCIDs were-7.8 mm and-8.6 mm, respectively. CONCLUSIONS: An 
      empirically validated non-inferiority margin of 10 mm for EAPP measured on a VAS 
      is appropriate to compare treatments in endometriosis.
FAU - Gerlinger, Christoph
AU  - Gerlinger C
AD  - Global Clinical Statistics, Bayer Schering Pharma AG, 13342 Berlin, Germany. 
      christoph.gerlinger@bayer.com
FAU - Schumacher, Ulrike
AU  - Schumacher U
FAU - Faustmann, Thomas
AU  - Faustmann T
FAU - Colligs, Antje
AU  - Colligs A
FAU - Schmitz, Heinz
AU  - Schmitz H
FAU - Seitz, Christian
AU  - Seitz C
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Multicenter Study
PT  - Randomized Controlled Trial
PT  - Research Support, Non-U.S. Gov't
DEP - 20101124
PL  - England
TA  - Health Qual Life Outcomes
JT  - Health and quality of life outcomes
JID - 101153626
SB  - IM
MH  - Adolescent
MH  - Adult
MH  - Endometriosis/*complications/therapy
MH  - Female
MH  - Humans
MH  - Laparoscopy
MH  - Middle Aged
MH  - Pain Measurement/*methods
MH  - Patient Satisfaction
MH  - Pelvic Pain/*physiopathology/psychology
MH  - Reproducibility of Results
MH  - Severity of Illness Index
MH  - Young Adult
PMC - PMC3002916
EDAT- 2010/11/26 06:00
MHDA- 2013/02/15 06:00
PMCR- 2010/11/24
CRDT- 2010/11/26 06:00
PHST- 2010/05/10 00:00 [received]
PHST- 2010/11/24 00:00 [accepted]
PHST- 2010/11/26 06:00 [entrez]
PHST- 2010/11/26 06:00 [pubmed]
PHST- 2013/02/15 06:00 [medline]
PHST- 2010/11/24 00:00 [pmc-release]
AID - 1477-7525-8-138 [pii]
AID - 10.1186/1477-7525-8-138 [doi]
PST - epublish
SO  - Health Qual Life Outcomes. 2010 Nov 24;8:138. doi: 10.1186/1477-7525-8-138.