Development and validation of measures of social phobia scrutiny fear and social interaction anxiety Richard P. Mattick a,b *, J. Christopher Clarke b a Clinical Research Unit for Anxiety Disorders, St Vincent's Hospital, Sydney, Australia b University of New South Wales, Sydney, Australia Received 1 October 1997 Abstract The development and validation of the Social Phobia Scale (SPS) and the Social Interaction Anxiety Scale (SIAS) two companion measures for assessing social phobia fears is described. The SPS assesses fears of being scrutinised during routine activities (eating, drinking, writing, etc.), while the SIAS assesses fears of more general social interaction, the scales corresponding to the DSM-III-R descriptions of Social PhobiaÐCircumscribed and Generalised types, respectively. Both scales were shown to possess high levels of internal consistency and test±retest reliability. They discriminated between social phobia, agoraphobia and simple phobia samples, and between social phobia and normal samples. The scales cor- related well with established measures of social anxiety, but were found to have low or non-signi®cant (partial) correlations with established measures of depression, state and trait anxiety, locus of control, and social desirability. The scales were found to change with treatment and to remain stable in the face of no-treatment. It appears that these scales are valid, useful, and easily scored measures for clinical and research applications, and that they represent an improvement over existing measures of social phobia. # 1998 Published by Elsevier Science Ltd. All rights reserved 1. Introduction Self-report scales are central to the measurement of both clinical status and therapy-outcome of the anxiety disorders. Over the last 20 years a large number of such scales have been devel- oped and re®ned. While many have measured social anxiety, little attention has been focused Behaviour Research and Therapy 36 (1998) 455±470 0005-7967/98/$19.00 # 1998 Published by Elsevier Science Ltd. All rights reserved. PII: S0005-7967(97)10031-6 BEHAVIOUR RESEARCH AND THERAPY PERGAMON Editor's note: This article was written before the development of some contemporary measures of social phobia, such as the Social Phobia and Anxiety Inventory (Turner et al., 1989). We have invited this article for publication because of the growing interest in the scales described therein. S.T. * Author for correspondence at: National Drug and Alcohol Research Centre, University of New South Wales, Sydney, NSW 2052, Australia.