Measuring States of Anxiety with Clinician-Rated and Patient-Rated Scales

Abstract

Most of the scales we use in clinical psychiatry when measuring mood and anxiety were developed more that three decades ago. Thus the Hamilton Anxiety Scale (HAM-A) (Hamilton 1969) is still the internationally most used clinician-rated scale within states of clinical anxiety, whereas Spielberger’s State Anxiety Scale (Spielberger, Gorsuch & Lushene 1970) or the Symptom Checklist (SCL-90) (Derogatis et al. 1974) are among the most frequently used patient-rated questionnaires. In her comprehensive content analysis of the items included in 27 different rating scales or questionnaires for clinical anxiety, de Bonis (1974) concluded that the HAM-A seems to cover the clinically most representative items for states of generalized anxiety. This can be considered in itself as one way of demonstrating the clinical validity of the HAM-A. As concerns questionnaires, the Spielberger State Anxiety Scale covers the psychic anxiety symptoms whereas the anxiety subscale of the SCL-90 contains more somatic anxiety symptoms than psychic anxiety symptoms (Derogatis et al. 1974). Although the SCL-90 includes some specific anxiety subscales, e.g., a phobia and an obsessive-compulsive (OCD) subscale, these anxiety subscales are also not sufficiently valid. The measurement of panic attacks is probably most validly measured in terms of minor versus major attacks, i.e. global assessments. The measurement of states of OCD is probably most validly measured by the duration of this state of anxiety, e.g. less or more than two hours daily. The Anxiety-Symptom-Scale (ASS) is shown in the Appendix as an example of a very short screening questionnaire covering the many subtypes of states of anxiety. In the following, it is the general state of anxiety as measured archetypically by the HAM-A, and by the corresponding self-rating scales that will be treated. The psychometric validation of these general anxiety scales became important with reference to the classes of drugs most frequently investigated in trials of anti-anxiety medication, namely tricyclic antidepressants (e.g., imipramine) versus benzodiazepines (e.g., diazepam). Early on, Derogatis et al (1974) demonstrated that whereas imipramine was superior to diazepam when using the SCL-90 subscale of depression, no differences were obtained when using the SCL-90 anxiety subscale. The landmark study in this respect was the study by Rickels et al (1993) which demonstrated that when treating patients with generalized anxiety disorder with imipramine versus diazepam in a placebo-controlled, randomised trial, imipramine was superior to benzodiazepine on the psychic factor in the HAM-A but not on the somatic factor in the HAM-A.