Table 3. Dimensions of DSM-IV/CIDI MDE lifetime onset-course and 12-month persistence-severity by age among WMH respondents with MDE.
| Age Groups | Age Difference | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| All ages | 18-34 | 35-49 | 50-64 | 65+ | |||||||
| Est | (se) | Est | (se) | Est | (se) | Est | (se) | Est | (se) | F/ χ2 | |
| I. Developed | |||||||||||
| A. Lifetime onset and course | |||||||||||
| Mean age of onset | 28.9 | (0.2) | 19.1 | (0.1) | 27.6 | (0.3) | 35.6 | (0.3) | 46.3 | (0.7) | 3717.2* |
| Mean number of lifetime episodes | 14.8 | (0.7) | 11.0 | (1.0) | 14.3 | (1.0) | 18.1 | (1.7) | 21.9 | (3.6) | 21.3* |
| (n) | (7917) | (2325) | (2764) | (1890) | (938) | ||||||
| B Twelve-month persistence and severity | |||||||||||
| Mean 12-month duration (in weeks) | 27.0 | (0.5) | 25.3 | (0.8) | 27.2 | (0.8) | 28.9 | (1.1) | 31.7 | (1.8) | 4.8* |
| Clinically severe (%)1 | 33.9 | (1.0) | 34.7 | (1.7) | 39.7 | (1.7) | 29.6 | (2.3) | 19.6 | (2.8) | 15.2* |
| Severe role impairment (%)2 | 65.8 | (1.3) | 65.3 | (2.0) | 68.2 | (2.2) | 66.2 | (3.2) | 54.8 | (4.7) | 12.4* |
| Mean days out of role | 48.3 | (1.4) | 49.2 | (2.2) | 52.5 | (2.3) | 46.4 | (3.5) | 25.5 | (4.4) | 12.4* |
| (n) | (2973) | (1079) | (990) | (625) | (279) | ||||||
| II. Developing | |||||||||||
| A. Lifetime onset and course | |||||||||||
| Mean age of onset | 27.2 | (0.2) | 19.3 | (0.2) | 29.1 | (0.3) | 38.5 | (0.6) | 40.3 | (1.1) | 1596.3* |
| Mean number of lifetime episodes | 10.9 | (0.9) | 5.7 | (0.5) | 9.7 | (1.3) | 13.8 | (1.9) | 35.3 | (6.7) | 36.1* |
| (n) | (4365) | (1640) | (1455) | (885) | (385) | ||||||
| B. Twelve-month persistence and severity | |||||||||||
| Mean 12-month duration (in weeks) | 26.0 | (0.7) | 23.1 | (1.1) | 25.4 | (1.1) | 29.2 | (1.2) | 33.8 | (2.3) | 3.6* |
| Clinically severe (%)1 | 41.8 | (1.2) | 38.3 | (1.8) | 47.8 | (2.5) | 43.7 | (2.8) | 36.8 | (3.5) | 3.7 |
| Severe role impairment (%)2 | 49.3 | (1.6) | 49.3 | (2.8) | 53.1 | (2.6) | 46.4 | (2.7) | 42.7 | (3.7) | 11.4* |
| Mean days out of role | 25.3 | (2.1) | 16.0 | (2.6) | 25.0 | (3.5) | 34.9 | (5.4) | 50.4 | (6.3) | 3.6* |
| (n) | (2293) | (898) | (732) | (455) | (208) | ||||||
Significant age difference at the .05 level, two-sided test.
The percent of cases whose depression was classified either severe or very severe on the self-report version of the Quick Inventory of Depressive Symptomatology[21]
The percent of cases whose depression-related role impairment was classified either severe or very severe on any dimension of the Sheehan Disability Scales[22]
Significance was evaluated with an F test for the means (age of onset, mean number of lifetime episodes, mean duration) and a χ2 test for the proportions (the percent of cases classified clinically mild, clinically severe, and having severe role impairment). The χ2 tests all have 3 degrees of freedom, while the F tests have 3 and 7913 degrees of freedom in developed countries and 3 and 4361 in developing countries for lifetime means and 3 and 2969 degrees of freedom in developed countries and 2289 degrees of freedom in developing countries for 12-month means.