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You often will hear people talk about the rate of depression, without discussing how that rate was obtained.There are multiple factors that will influence this: the group from which you are interviewing people (the “sampling frame”), the time period over which you are asking, and the survey method. In general, there are two types of survey: fully structured, best considered as Yes or No answers, or semi structured, where the interviewer can probe and makes a decision as to if the symptom is absent, subclinical, present, or severe.

You can now look at this table, extracted from a meta analysis.

I have used the SCAN it is very long, taking one to six hours to complete. The SCID is much quicker. I have not used the DISH. Of the structured measurements, almost all epidemological surveys in the community use the CIDI. The DIS, MINI and CIS-R are often used as screening tools for clincial trials. From the same paper, uwing a generalized tool of distress, the semistrucutred interviews diagnose more at higher levels of distress and less and lower levels of distress than the strucutred interviews.

a) Probability of major depression classification by PHQ-9 score for semi-structured interviews, fully structured interviews (excluding the MINI) and the MINI. Proportions are plotted as three-point moving averages (e.g. the proportions at the PHQ-9 score of 10 are averages of the proportions at PHQ-9 scores of 9, 10, and 11). (b) Difference in probability of major depression classification by PHQ-9 score for semi-structured interviews and the MINI compared with fully structured interviews (excluding the MINI). Differences in proportions are plotted as three-point moving averages (e.g. the differences in proportions at the PHQ-9 score of 10 are averages of the differences in proportions at PHQ-9 scores of 9, 10, and 11). MINI: Mini International Neuropsychiatric Interview; PHQ-9: Patient Health Questionnaire-9.

The authors summarized it thusly.

A total of 17 158 participants (2287 with major depression) from 57 primary studies were analysed. Among fully structured interviews, odds of major depression were higher for the MINI compared with the Composite International Diagnostic Interview (CIDI) (odds ratio (OR) = 2.10; 95% CI = 1.15–3.87). Compared with semi-structured interviews, fully structured interviews (MINI excluded) were non-significantly more likely to classify participants with low-level depressive symptoms (PHQ-9 scores ?6) as having major depression (OR = 3.13; 95% CI = 0.98–10.00), similarly likely for moderate-level symptoms (PHQ-9 scores 7–15) (OR = 0.96; 95% CI = 0.56–1.66) and significantly less likely for high-level symptoms (PHQ-9 scores ?16) (OR = 0.50; 95% CI = 0.26–0.97).
Levis B, Benedetti A, Riehm KE, Saadat N, Levis AW, Azar M, et al. Probability of major depression diagnostic classification using semi-structured versus fully structured diagnostic interviews. The British Journal of Psychiatry. Cambridge University Press; 2018;:1–9.

Always ask what instrument was used, and alwayes question the population it was used in. Without that data, the numbers make no sense.

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