Background: A growing body of evidence has highlighted the significant relationship between social anxiety disorder and hazardous alcohol consumption, harmful use, and alcohol use disorder. This relationship may influence the reporting of fear and avoidance of social or performance situations on common self-report measures among individuals with hazardous alcohol use or dependence. Method: The current study utilized modern psychometric methods, namely Item Response Theory (IRT) and Differential Item Functioning (DIF), in an online sample of Australian adults (n = 1052) to examine the potential under- or over-reporting of items on the Social Interaction Anxiety and Social Phobia Scales (SIAS/SPS) by groups of alcohol users (as measured by the Alcohol Use Disorders Identification Test), while controlling for underlying levels of social anxiety severity. Results: The results indicated that there were no items on the SIAS/SPS that exhibited significant (p < 0.01) and meaningful DIF (based on an a priori cutoff of change in pseudo-R2 across nested models >0.05) attributable to either hazardous consumption or symptoms of alcohol dependence. Moreover, the combined effect of multiple items that demonstrated significant (but non-meaningful) DIF on total SIAS scores relative to scores that assume no DIF between alcohol using groups was minimal. Conclusions: This study suggests that different rates of social anxiety across levels of alcohol consumption and alcohol dependence may not be the result of a systematic under- or over-reporting of certain items on the SIAS and SPS, and as such total social anxiety scores can be compared regardless of the level of alcohol use or dependence symptoms.
- social anxiety
- alcohol use
- alcohol dependence
- differential item functioning
- item response theory