Development and validation of the scale to assess satisfaction with medications for addiction treatment-methadone for heroin addiction (SASMAT-METHER)

Drug Alcohol Depend. 2014 Sep 1:142:79-85. doi: 10.1016/j.drugalcdep.2014.05.024. Epub 2014 Jun 11.

Abstract

Objective: To develop and examine the psychometric properties of a scale to specifically assess satisfaction with methadone in heroin-dependent patients.

Methods: The 44-item preliminary version of the scale to assess satisfaction with medications for addiction treatment-methadone for heroin addiction (SASMAT-METHER) was obtained from a pool of items designed to assess satisfaction with any medication-addiction combination. Theoretical domains of the initial SASMAT-METHER were overall satisfaction, pharmacotherapy, initiation, anti-addictive effect on heroin, mental state, physical state, personal functioning, acceptability, and anti-addictive effect on secondary substances. The Treatment Satisfaction Questionnaire for Medication 1.4 version (TSQM 1.4) and the Verona Service Satisfaction Scale for Methadone Treatment (VSSS-MT) were used for concurrent validation. Participants included heroin-dependent patients receiving methadone treatment for at least the last 3 months.

Results: The preliminary version of the SASMAT-METHER scale was completed by 241 patients, with 180 surveys considered suitable for factor analysis. Principal component analysis of these SASMAT-METHER surveys revealed a 3-factor structure that accounted for 40.4% of total variance. Based on similarities between empirically-obtained factors and theoretical domains, factors 1 through 3 were named 'Personal Functioning and Well-Being' (7 items), 'Anti-Addictive Effect on Heroin' (5 items), and 'Anti-Addictive Effect on Other Substances' (5 items). All factors showed good to excellent internal consistency (Cronbach's α: 0.83-0.92) and test-retest reliability (intraclass correlation coefficients: 0.66-0.89). Correlations between overall SASMAT-METHER and TSQM 1.4 scores were stronger (Pearson r=0.69) than correlations between overall SASMAT-METHER and VSSS-MT scores (Pearson r=0.26).

Conclusion: These results present evidence for the validity and reliability of SASMAT-METHER.

Keywords: Factor structure; Heroin addiction; Methadone; Patient satisfaction; Validation study.

Publication types

  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Adult
  • Female
  • Heroin Dependence / drug therapy*
  • Heroin Dependence / psychology
  • Humans
  • Male
  • Methadone / therapeutic use*
  • Middle Aged
  • Patient Satisfaction*
  • Psychometrics
  • Reproducibility of Results
  • Surveys and Questionnaires*
  • Treatment Outcome

Substances

  • Methadone