Design Cohort study using the general practice research database.
Baseline variables were derived using the general practice data (see codes in Additional file 1).
Prescriptions issued by doctors using the general practice research database are automatically transcribed into the computer record.
This study used the general practice research database and involved 100 000 statin users followed for under three years.
In recent years, there has been a research-based focus on using the general practice setting for health promotion including improving dietary and exercise practices among patients, particularly for weight management.
A cohort study 9 in patients aged 18 to 89 using the general practice research database found that venlafaxine use was associated with a higher risk of suicide and attempted suicide than was citalopram, fluoxetine, and dothiepin.
The authors concluded that this could reflect residual confounding since they found that venlafaxine users had a higher burden of risk factors for suicide, as was also the case in a previous study using the general practice research database.
Previously we used the general practice research database to study the incidence of cancers in patients presenting in primary care with four "alarm symptoms"—haematuria, dysphagia, haemoptysis, and rectal bleeding.
15 16 17 18 Using the general practice research database, we identified all patients who were prescribed their first ever oral antidiabetic agent, with at least one year of medical history in the database before that prescription, between 1 January 1988 and 31 December 2009.
Non-index cohort: Using the general practice records for the same time period (2006 2010), a random sample stratified by practice of all adults aged 40 years and over without a historical record or consultation for the study specific CVD and OA codes will be identified.
OA cohort: Using the general practice records for the same time period (2006 2010), all adults aged 40 years and over, who are actively registered and who either have a historical record or consultation for OA Readd and daughter codes beginning with N05, and codes related to OA joint replacement (7 K2 or 7 K3)) will be identified.
