Concurrent validation of the Clinical Opiate Withdrawal Scale (COWS) and single-item indices against the Clinical Institute Narcotic Assessment (CINA) opioid withdrawal instrument.
BACKGROUND
The Clinical Opiate Withdrawal Scale (COWS) is an 11-item clinician-administered scale assessing opioid withdrawal. Though commonly used in clinical practice, it has not been systematically validated. The present study validated the COWS in comparison to the validated Clinical Institute Narcotic Assessment (CINA) scale.


METHODS
Opioid-dependent volunteers were enrolled in a residential trial and stabilized on morphine 30 mg given subcutaneously four times daily. Subjects then underwent double-blind, randomized challenges of intramuscularly administered placebo and naloxone (0.4 mg) on separate days, during which the COWS, CINA, and visual analog scale (VAS) assessments were concurrently obtained. Subjects completing both challenges were included (N=46). Correlations between mean peak COWS and CINA scores as well as self-report VAS questions were calculated.


RESULTS
Mean peak COWS and CINA scores of 7.6 and 24.4, respectively, occurred on average 30 min post-injection of naloxone. Mean COWS and CINA scores 30 min after placebo injection were 1.3 and 18.9, respectively. The Pearson's correlation coefficient for peak COWS and CINA scores during the naloxone challenge session was 0.85 (p<0.001). Peak COWS scores also correlated well with peak VAS self-report scores of bad drug effect (r=0.57, p<0.001) and feeling sick (r=0.57, p<0.001), providing additional evidence of concurrent validity. Placebo was not associated with any significant elevation of COWS, CINA, or VAS scores, indicating discriminant validity. Cronbach's alpha for the COWS was 0.78, indicating good internal consistency (reliability).


CONCLUSIONS
COWS, CINA, and certain VAS items are all valid measurement tools for acute opiate withdrawal.
Tompkins
D Andrew
DA
Johns Hopkins University School of Medicine, Department of Psychiatry and Behavioral Sciences, Behavioral Pharmacology Research Unit, 5510 Nathan Shock Drive, Baltimore, MD 21224, USA. dtompki1@jhmi.edu
Bigelow
George E
GE
Harrison
Joseph A
JA
Johnson
Rolley E
RE
Fudala
Paul J
PJ
Strain
Eric C
EC
D000293:Adolescent; D000328:Adult; D000368:Aged; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000494:pharmacology; D009270:Naloxone; D009292:Narcotic Antagonists; D009294:Narcotics / Q000494:pharmacology; D009293:Opioid-Related Disorders / Q000175:diagnosis* / Q000523:psychology; D011569:Psychiatric Status Rating Scales; D011680:Pupil / Q000187:drug effects; D015203:Reproducibility of Results; D013375:Substance Withdrawal Syndrome / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology; D055815:Young Adult
D009292:Narcotic Antagonists; D009294:Narcotics; D009270:Naloxone; D009020:Morphine