A validation analysis of two self-reported HAM-D6 versions.
OBJECTIVE
The six items of the clinician-administrated Hamilton Depression Scale (HAM-D(6)) cover the core items of depressive states reflecting the antidepressive effect of medication. In this study, the two self-reported versions of the HAM-D(6) have been psychometrically validated to ensure the unidimensionality of this administration form in patients with mild-to-moderate depression.


METHODS
The item response theory analysis of Mokken was used to test the unidimensionality of both the Interactive Voice Recording System (IVRS) version of the HAM-D(6) and a paper-and-pencil self-reported version (S-HAM-D(6)). Patients with typical major depression and with seasonal affective disorder were included.


RESULTS
The Mokken analysis showed that the two self-reported versions of the HAM-D(6) obtained coefficients of homogeneity above 0.40, similar to the clinician-rated HAM-D(6) and thus implying unidimensionality. By contrast, the full HAM-D(17) versions (self-reported as well as clinician-rated) obtained coefficients of homogeneity below 0.40, implying that the HAM-D(17) is a multidimensional scale.


CONCLUSIONS
The analysis show that both the IVRS version and the S-HAM-D(6) version are unidimensional self-rating scales for the measurement of depressive states.
Bech
P
P
Psychiatric Research Unit, Frederiksborg General Hospital, Copenhagen University Hospitals, Hilleroed, Denmark. pebe@noh.regionh.dk
Wilson
P
P
Wessel
T
T
Lunde
M
M
Fava
M
M
D000328:Adult; D000928:Antidepressive Agents / Q000627:therapeutic use; D003865:Major Depressive Disorder / Q000175:diagnosis* / Q000188:drug therapy / Q000523:psychology; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006801:Humans; D008297:Male; D011594:Psychometrics; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires
D000928:Antidepressive Agents