Development and psychometrics of the five item daily index in a psychiatric sample

Effective treatment of affective disorders requires the ability to reliably monitor patient progress and outcome. The current study aimed to establish the Daily Index-5 (DI-5) as a psychometrically sound and clinically valid measure of treatment response in psychiatric care for use as a companion measure with the WHO Wellbeing Index (WHO-5; Bech et al., 1996. Psychother. Psychosom. 65, 183-190.).

Eight hundred and ninety four consecutive inpatients and day-patients at a psychiatric facility completed the DI-5, WHO-5, SF-36 (Ware et al., 1993. SF-36 Health Survey: Manual and Interpretation Guide. The Health Institute, New England Medical Centre, Boston, MA.) and DASS-21 (Lovibond and Lovibond, 1995b. Manual for the Depression Anxiety Stress Scales. Psychology Foundation, Sydney, Australia.; Ware et al., 1993. SF-36 Health Survey: Manual and Interpretation Guide. The Health Institute, New England Medical Centre, Boston, MA.) routinely during treatment.

The DI-5 was shown to be a measure with high reliability and validity. In addition criteria for clinically significant recovery are presented with an example implementation of a Clinical Significance Monitoring system. Finally, the latent structure of the DI-5 is established as a uni-dimensional index of affective disorder.

The results may be generalized to samples with primary diagnoses of depressive and/or anxiety disorders though assessment of the DI-5 as a measure of treatment response is warranted in patients with other primary diagnoses.

The current study indicates that the DI-5 is a quick to administer and interpret, reliable and valid measure for assessing patient outcome that is appropriate for use in monitoring patient change.