| Events in a typical RCT |
Events in the real world |
|
| Patients are recruited from specialist centres, or by advertising |
Patients are mainly treated in primary care |
| Patients with comorbid medical or psychiatric disorders are excluded |
Patients are probably treated whatever comorbid disorders are present |
| Patients are carefully selected to generate homogeneous diagnostic groups according to DSM and ICD |
Patients with heterogeneous diagnoses according to DSM or ICD are ‘lumped’ together |
| Patients are allocated the treatment at random |
Treatment is allocated via a complex process of explanation and negotiation |
| Patients are given detailed information (which may be overinclusive) for informed consent |
Patients provided brief information (which may be underinclusive) for informed consent |
| Patients are given a 1-week placebo run-in period to remove placebo responders |
All patients are given active treatment from the start |
| Placebo is used to compare active treatment |
No placebo is used: choice is between active treatment and no treatment |
| Patients are followed at frequent intervals and given detailed checklists of side-effects |
Patients are followed at very varying intervals according to haphazard practice |
| Assessment end-point is typically 4–6 weeks after treatment begins |
Patients continue on treatment for 6 months, and patient and clinician are interested in much longer end-points |
| Assessment of outcome is based on depressive symptoms and side-effects |
To patient and doctor, functional outcomes (e.g. return to work) may be more important |
| Patient and clinician are blind to treatment group |
Both (usually) are aware of the drug the patient is given |