Figure 2.

The prevalence rates of dysthymic disorder by assumed input symptom prevalence and correlations. Dysthymic disorder is diagnosed when both the major (depressed mood most of the day for more days than not, for at least 2 years) and minor criteria (at least two of the six items) are met. The black line represents the situation where the prevalence rates of the input symptoms are the same as those of dysthymic disorder. Lines below the black lines have dysthymic disorder prevalence rates lower than those of the input symptoms. CI, confidence interval.