title: Validation of the Orbach & Mikulincer Mental Pain Scale (OMMP) on a drug addicted population.
abstract: OBJECTIVE
  Recognizing the relevance of mental pain in drug addiction, this study aimed to adapt and validate the Portuguese translation of the Orbach & Mikulincer Mental Pain Scale (OMMP) on a drug addicted population and assess its psychometric properties.
  
  
  METHODS
  The study sample (N = 403) was collected from several outpatient treatment centres for drug addiction and in therapeutic communities located in the north of Portugal. The validation of the OMMP Scale followed the same method considered by the authors of the original scale.
  
  
  RESULTS
  A confirmatory factor analysis (CFA) was performed and did not confirm the structure of eight factors provided by the authors. An exploratory factor analysis revealed a five-factor model (labeled emptiness, irreversibility, emotional flooding, helplessness and confusion) leading to a reduction from 40 to 24 items. The OMMP-24-P showed acceptable levels for internal consistency and test-retest reliability. Confirmatory factor analysis indices supported the five-factor model. OMMP-24-P factors were positively correlated with measures of stress, anxiety and depression, negatively associated with quality of life, and showed small to moderate positive correlations with drug addiction severity, with exception of the helplessness factor.
  
  
  CONCLUSIONS
  This study has shown the OMMP-24-P to be a valid and reliable scale for assessment and evaluation of mental pain among drug addicts. Further research should attempt to determine the contribution that mental pain can provide towards an understanding of drug addiction dynamics and other psychopathological syndromes, and thereby contribute to the development of more effective treatment programs.
authors.affiliation: ICBAS, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313, Porto, Portugal.
authors.forename: Rui
authors.initials: R
authors.lastname: Guimarães
authors.forename: Manuela
authors.initials: M
authors.lastname: Fleming
authors.forename: Margarida Fonseca
authors.initials: MF
authors.lastname: Cardoso
mesh_terms: D000293:Adolescent; D000328:Adult; D001007:Anxiety / Q000150:complications; D003863:Depression / Q000150:complications; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000523:psychology*; D011174:Portugal; D011594:Psychometrics / Q000379:methods*; D011788:Quality of Life; D019966:Substance-Related Disorders / Q000150:complications / Q000175:diagnosis* / Q000523:psychology*; D014177:Translations; D055815:Young Adult