title: Searching for success: Development of a combined patient-reported-outcome ("PRO") criterion for operationalizing success in multi-modal pain therapy.
abstract: BACKGROUND
  There is a need for a way to measure success in multi-modal pain therapy that researchers and clinicians can agree upon. According to developments in health services research, operationalizing success should take patient-reported outcomes into account. We will present a success criterion for pain therapy that combines different patient-reported variables and includes validity measures. The usable criterion should be part of a statistically significant and satisfactory model identifying predictors of successful pain therapy.
  
  
  METHODS
  Routine data from 375 patients treated with multi-modal pain therapy from 2008 to 2013 were used. The change scores of five constructs were used for the combined success criterion: pain severity, disability due to pain, depressiveness, and physical- and mental-health-related quality of life. According to the literature, an improvement of at least ½ standard deviation was required on at least four of the five constructs to count as successful. A three-step analytical approach including multiple binary logistic regression analysis was chosen to identify the predictors of therapy success with the success criterion as the dependent variable.
  
  
  RESULTS
  A total of 58.1% of the patients were classified as successful. Convergent and predictive validity data show significant correlations between the criterion and established instruments, while discriminative validity could also be shown. A multiple binary logistic regression analysis confirmed the feasibility; a significant model (Chi(2) (8) = 52.585; p < .001) that explained 17.6% of the variance identified the following predictors of therapy success: highest pain severity in the last 4 weeks, disability due to pain, and number of physician visits in the last 6 months.
  
  
  CONCLUSIONS
  It is possible to develop a feasible success criterion that combines several variables and includes patient-reported outcomes ("PROs") with routine data that can be used in a predictor analysis in multi-modal pain therapy. The criterion was based on basic constructs used in pain therapy and used widespread validated self-rating instruments. Thus, it should be easy to transfer this criterion to other institutions.
authors.affiliation: Department of Psychiatry and Psychotherapy, Center for Health Services Research in Medicine, Friedrich-Alexander-Universität Erlangen-Nürnberg, Schwabachanlage 6, 91054, Erlangen, Germany. carolin.donath@uk-erlangen.de.
authors.forename: Carolin
authors.initials: C
authors.lastname: Donath
authors.affiliation: Department of Psychiatry and Psychotherapy, Center for Health Services Research in Medicine, Friedrich-Alexander-Universität Erlangen-Nürnberg, Schwabachanlage 6, 91054, Erlangen, Germany. lisa.dorscht@uk-erlangen.de.|Interdisciplinary Pain Center, University Clinic Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Krankenhausstr. 12, 91054, Erlangen, Germany. lisa.dorscht@uk-erlangen.de.
authors.forename: Lisa
authors.initials: L
authors.lastname: Dorscht
authors.affiliation: Department of Psychiatry and Psychotherapy, Center for Health Services Research in Medicine, Friedrich-Alexander-Universität Erlangen-Nürnberg, Schwabachanlage 6, 91054, Erlangen, Germany. elmar.graessel@uk-erlangen.de.
authors.forename: Elmar
authors.initials: E
authors.lastname: Graessel
authors.affiliation: Interdisciplinary Pain Center, University Clinic Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Krankenhausstr. 12, 91054, Erlangen, Germany. reinhard.sittl@uk-erlangen.de.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Sittl
authors.affiliation: Interdisciplinary Pain Center, University Clinic Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Krankenhausstr. 12, 91054, Erlangen, Germany. christoph.schoen@uk-erlangen.de.
authors.forename: Christoph
authors.initials: C
authors.lastname: Schoen
mesh_terms: D000328:Adult; D003131:Combined Modality Therapy; D005260:Female; D005858:Germany; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D059408:Pain Management / Q000379:methods*; D063868:Patient Outcome Assessment; D010808:Physical Examination; D011787:Quality of Health Care; D011788:Quality of Life; D057566:Self Report