Reliability and validity of the Spanish version of the substance dependence severity scale.
OBJECTIVE
The purpose of this study was to estimate the reliability and provide evidence for the validity of the Spanish version of the Substance Dependence Severity Scale (SDSS).


METHODS
A total of 211 substance abusers recruited at a public center that provides treatment for substance-related disorders in an outpatient setting were assessed. Reliability was estimated by Cronbach's α and test-retest. Validity evidence was studied by analyzing the relationships with the European Addiction Severity Index (EuropASI) and Health-Related Quality of Life for Drug Abusers (HRQoLDA).


RESULTS
Adequate reliability coefficients were found for the dependence scales of all addressed substances (α = 0.737 to 0.877; test-retest r = 0.796-0.952). Low internal consistency was found for the abuse scales (α = 0.329-0.694), and adequate test-retest coefficients on alcohol, cocaine and heroin (test-retest r = 0.708-0.902). The reliability of the cannabis abuse scales was inadequate. The SDSS scores showed significant relationships with the EuropASI and HRQoLDA dimensions.


CONCLUSIONS
The psychometric analyses validate the use of the severity of dependence scales. The SDSS abuse scales must be used taking the limitations detected into consideration.
Department of Clinical, Experimental and Social Psychology, University of Huelva, Huelva, Spain.
Antonio
A
Vélez-Moreno
Francisco
F
González-Saiz
Antonio J
AJ
Rojas
Esperanza
E
Torrico-Linares
Fermín
F
Fernández-Calderón
Juan
J
Ramírez-López
Oscar M
OM
Lozano
D000328:Adult; D000437:Alcoholism / Q000175:diagnosis*; D019970:Cocaine-Related Disorders / Q000175:diagnosis*; D005260:Female; D006556:Heroin Dependence / Q000175:diagnosis*; D006801:Humans; D008297:Male; D002189:Marijuana Abuse / Q000175:diagnosis*; D008875:Middle Aged; D011594:Psychometrics; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D019966:Substance-Related Disorders / Q000175:diagnosis; D011795:Surveys and Questionnaires; D014177:Translations