An eleven item clinician-administered Mania Rating Scale (MRS) is introduced, and its reliability, validity and sensitivity are examined. There was a high correlation between the scores of two independent clinicians on both the total score (0.93) and the individual item scores (0.66 to 0.92). The MRS score correlated highly with an independent global rating, and with scores of two other mania rating scales administered concurrently. The score also correlated with the number of days of subsequent stay in hospital. It was able to differentiate statistically patients before and after two weeks of treatment and to distinguish levels of severity based on the global rating.

The Zung Self-rating Depression Scale (ZSDS) correlated well (0.69) with the treating physician's global rating in 26 depressed out-patients during the six weeks of treatment with a tricyclic anti-depressant. In a larger sample of 41 patients, a high correlation was found between the ZSDS and the Hamilton Rating Scale. The sensitivity of the ZSDS was found to be adequate. The scale was able to differentiate, at the 0.05 level, four severity groups classified on the basis of the global rating. The importance of the direct relationship between the range of severity studied and the value of the correlation coefficient was discussed. Previous investigations and the results of this study indicate that the ZSDS is a valid and sensitive measure of clinical severity in depressed patients and support its continued use as a research instrument.

In 26 depressed patients, a high correlation (0-89) was found between the Hamilton score and a psychiatrist's global rating and between the change (0-68) in these ratings during treatment. The Hamilton scale was able to differentiate at the o-01 level four degrees of severity based on the global rating. Limiting the range of severity measured was found to lower significantly the correlation between the ratings. A prospective examination of a six-item sub-scale of the Hamilton scale developed by Beck and associates failed to confirm its claimed improvement in sensitivity or validity.

Eighteen depressed outpatients were treated for 6 wk with a mean daily dose of 121 mg of nortriptyline. The mean plasma level was 138 ng/ml during treatment. Therapeutic response was monitored by the Zung Self-Rating Depression Scale and the Hamilton Depression Scale administrered by two psychiatrists blind to the tricyclic used, dose, and plasma levels. Eight patients recovered (Hamilton less than or equal to 6) by the fourth week and 12 by the sixth week. During the steady-state (wk 4 to 6) there was a positive correlation between the weekly Hamilton scores and the weekly nortriptyline levels (p less than 0.01). The 9 patients with mean plasma levels between 50 and 139 ng/ml had a better therapeutic response after 6 wk measured by percent recovered (p less than 0.005). Zung score (p less than 0.05), and Hamilton score (p less than 0.025) than the 9 patients with mean plasma levels between 140 and 260 ng/ml.