This study collected and studied data from three different Netherlands studies: Netherlands Study of Depression and Anxiety (NESDA), Netherlands Study of Depression in Older Persons (NESDO), and Netherlands Obsessive Compulsive Disorder Association Study (NOCDA)

• NESDA; study of people from ages 18 to 65. 2329 people in the study have depression or anxiety and 652 without a mental health disorder
• NESDO; study of people from ages 60 to 83. 378 of them have depressive disorder and 652 with non lifetime diagnosis of depression, anxiety, dementia, or another psychiatric disorder -NOCDA; study of 419 people between the ages of 18 and 65 with lifetime OCD