Background: Despite its importance, no distinction between moderate and severe depression using the Montgomery-Asberg Depression Rating Scale (MADRS) based on a direct comparison with the Hamilton Depression Rating Scale (HAMD-17) is available.
Methods: HAMD-17 and MADRS ratings from N=40 at least moderately depressed inpatients with major depression (DSM-III-R) were analyzed. Linear and non-parametric correlations were computed and a MADRS cut-off score for severe depression using an HAMD-17 score of at least 28 points as reference was estimated.
Results: HAMD-17 and MADRS mean scores were 24.6+/-4.3 and 32.6+/-5.0 points, respectively. Linear correlation of both scores was r=0.70 (P<0.0005). A MADRS cut-off score of at least 35 points was estimated to separate 'moderate' from 'severe' depression corresponding to a HAMD-17 cut-off of 28 points with sufficient sensitivity and specificity.
Limitations: The sample size was limited and no observer ratings directly assessing the severity of depression were used.
Conclusions: The preliminary findings are in line with previous findings and suggest a cut-off score of 35 points to separate moderate from severe depression with the MADRS accepting an HAMD-17 score of >/=28 point as reference. Further studies on this issue are warranted.