Objective: To estimate the prevalence rate of major depression in the Danish general population by using the Major Depression Inventory (MDI), a validated self-rating scale fulfilling the symptomatic criteria in DSM-IV and ICD-10 for a depressive episode.
Method: A booklet containing the MDI and a number of questions on psychosocial factors was sent to 2040 randomly selected Danish citizens. The sample was age- and gender-stratified. Mean MDI scores were calculated. Logistic regression analysis was used in order to produce a model for the influence of psychosocial factors.
Results: The response rate was 60%. The point prevalence of major depression was 3.3%. Among the tested predictors of depression were sociodemographic variables, alcohol and smoking habit, bodily pain, somatic diseases and traumatic life events. For a traumatic event in personal life over the past year odds ratio was 6.4 [2.7; 15.5], for overconsumption of alcohol odds ratio was 3.2 [1.5; 6.8]. While the gender difference in major depression rate was not found statistically significant, a significant (P < 0.05) gender difference of male to female of 1 : 2 was found when including minor depression. Of people identified as having a major depression only 13% were currently treated by a medical doctor.
Conclusion: Major depression has a high prevalence in the Danish general population and seems to be undertreated. The gender difference was only found statistically significant when including minor depression, indicating that the female predominance is less pronounced in the more severe depression states.