Development and validation of a brief screening tool for over-the-counter codeine dependence

Area of Science:

• Pharmacology and Pharmacy Practice
• Addiction Medicine
• Psychometrics

Background:

• Low-dose codeine is accessible over-the-counter in several countries, raising concerns about misuse.
• Identifying individuals at risk of codeine dependence is crucial for preventing adverse outcomes.

Purpose of the Study:

• To develop and validate a concise screening tool for assessing codeine dependence risk.
• The tool is designed for practical implementation in community pharmacy settings.

Main Methods:

• Two studies were conducted for scale development and validation.
• Item generation involved analyzing psychosocial and pharmacy variables from frequent codeine users (N=795).
• Confirmatory Factor Analysis (CFA) and Receiver Operating Characteristic (ROC) analyses were used, with the Severity of Dependence Scale and DSM-5 Opioid Use Disorder (OUD) criteria (AUDADIS-IV) for validation.

Main Results:

• The four-item Codeine Dependence Scale (CDS) with a cut-off of ≥2 demonstrated 76% sensitivity and 48% specificity against DSM-5 codeine-related OUD.
• Longitudinally, the CDS achieved a 72% correct classification rate for positive codeine-related OUD cases at 15 months post-baseline.

Conclusions:

• The CDS offers reasonable sensitivity for identifying codeine dependence risk, though specificity is limited by its brevity.
• Its non-confrontational items facilitate pharmacist-led brief interventions (SBI) in community pharmacies for over-the-counter codeine users.