This paper demonstrates how compilation of medical and drug code lists for outcomes or exposures of interest for studies using primary care databases can be carried out efficiently using Stata. Use of Stata do-files to record and execute the commands provides good documentation and ease of replication of the procedure.

Participants: A total of 86 957 mother, father, and child triads identified in The Health Improvement Network database by linking mothers and babies and then identifying an adult household man. Depressed parents were identified using Read code entries for depression and antidepressant prescriptions. Main Exposures: Child age, parental age at the birth, and area deprivation quintile. Main Outcome Measures: Incidence rates for maternal and paternal episodes of depression. Results: Overall incidences of depression from the birth of the child up to age 12 years were 7.53 per 100 personyears for mothers and 2.69 per 100 person-years for fathers. Depression was highest in the first year post partum (13.93 and 3.56 per 100 person-years among mothers and fathers, respectively). By 12 years of child age, 39% of mothers and 21% of fathers had experienced an episode of depression. A history of depression, lower parental age at the birth of the child, and higher social deprivation were associated with a higher incidence of parental depression. Conclusions: Parents are at highest risk for depression in the first year after the birth of their child. Parents with a history of depression, younger parents, and those from deprived areas are particularly vulnerable to depression. There is a need for appropriate recognition and management of parental depression in primary care.