HTS: Hamilton Anxiety Scale

HTS offers the IVR version of the HAMA. For information on the paper and pencil clinician-administered HAMA, please reference the following article (HTS does not sell the paper and pencil version of the HAMA - this scale is in the public domain):

Guy, William, "048 HAMA Hamilton Anxiety Scale," ECDEU Assessment Manual, U.S. Department of Health and Human Services, Public Health Service - Alcohol, Drug Abuse, and Mental Health Administration, Rev. 1976, pp. 194-198.

The Hamilton Anxiety Scale consists of 14 items, each defined by a series of symptoms. As was the case with the HAMD, Hamilton provided only general guidelines regarding the administration and scoring of the scale. No standardized probe questions to elicit information from patients or behaviorally specific guidelines were developed for determining item scoring. Similar to the HAMD, each item is rated on a 5-point scale, ranging from 0 (not present) to 4 (severe).

The HAMA was one of the first rating scales developed to quantify the severity of anxiety symptomatology. Since its introduction by Max Hamilton in 1959, it has become a widely used and accepted outcome measure for the evaluation of anxiety in clinical trials. It was included in the National Institute of Mental Health's Early Clinical Drug Evaluation Program Assessment Manual, designed to provide a standard battery of assessments for use in psychotropic drug evaluation.

A number of validation studies of the clinician HAMA document its psychometric properties. Several validation studies have also been conducted of the computer HAMA. In the first, 292 adults were administered both a desktop and clinician HAMA in counterbalanced order. Internal scale consistency (coefficient alpha) was high (.92) and the mean item-to-total scale correlation was .65. The test-retest reliability was .96. The correlation between the computer and clinician HAMA scores was .92, providing support for the concurrent validity of the computer HAMA. The mean score difference between the computer and clinician HAMA scores for the total sample was small (1.37 points) but significant. However, for subjects with an anxiety disorder the difference in scores between HAMA versions was not significant.

An IVR version of the HAMA was developed using slight modification of the desktop version. In a validation study 72 subjects were given the clinician and IVR HAMA in counterbalanced order. Subjects were retested 24 hours later with both versions. Internal scale consistency reliability was .93 and the mean item-to-total scale correlation was .67, indicating a high level of internal consistency reliability. Test-retest reliability was .97, and mean score differences (.23 of a point) between test and retest were not significant. Correlation of the IVR and clinician HAMA was .65 and the IVR HAMA was correlated with the Beck Anxiety Inventory (r = .52). The mean score difference between the IVR and clinician (0.60 of a point) was not statistically significant providing further evidence of concurrent validity.

A study of the IVR HAMA examining the clinical utility of obtaining remote IVR ratings of generalized anxiety directly from patients was recently conducted in a phase II clinical drug trial. Following an initial screening, patients with a minimum baseline score of 20 on the clinician HAMA entered a one-week secondary screening period. During this period, patients telephoned the IVR system daily from home, using a toll free number, and were administered the IVR HAMA. Subjects who maintained a minimum mean HAMA score of 20 and whose mean score did not drop by more than 20% from baseline were randomized into the trial. A total of 19 patients met all the protocol requirements at the screening visit and entered the week long secondary screening phase using the IVR HAMA. All 19 patients (100%) completed all the required phone calls, and only one call was made on the wrong day (i.e., one call was made one day late, resulting in two calls in one day). None of the 19 patients needed a reminder call from the study coordinator to phone into the system as a result of noncompliance.