Balancing benefits and harms in health care:

Editor—The correspondence on the issue of including observational data of harm in systematic reviews surprised us.1,2 The tone of the prose implied that this might happen in the future, and the limits of randomised controlled trials discussed told readers what anyone working in assessing adverse events knows only too well. Observational data have been included in systematic reviews of possible harms for some time, precisely for the reasons that Johnston illustrates for vaccinations.2

[1]  C. Barbui.  Antidepressants and the risk of suicidal behaviors. , 2004, JAMA.

[2]  M. Pirmohamed,et al.  Adverse drug reactions as cause of admission to hospital: prospective analysis of 18 820 patients , 2004, BMJ : British Medical Journal.

[3]  Liza Gibson,et al.  WHO warns of a polio epidemic in Africa , 2004, BMJ : British Medical Journal.

[4]  E. García‐Berthou,et al.  Incongruence between test statistics and P values in medical papers , 2004 .

[5]  J. Lönnqvist,et al.  Completed suicide after a suicide attempt: a 37-year follow-up study. , 2004, The American journal of psychiatry.

[6]  D. Nutt.  Death and Dependence: Current Controversies over the Selective Serotonin Reuptake Inhibitors , 2003, Journal of psychopharmacology.

[7]  J. Lönnqvist,et al.  Inadequate treatment for major depression both before and after attempted suicide. , 1998, American Journal of Psychiatry.

[8]  R. Sykes.  Being a modern pharmaceutical company , 1998, BMJ.

[9]  Josie M. M. Evans,et al.  Aspirin, Nonsteroidal Anti-Inflammatory Drugs, and Epistaxis , 1998, The Annals of otology, rhinology, and laryngology.

[10]  H. Jick,et al.  Antidepressants and suicide , 1995, BMJ.

[11]  O. Aasland,et al.  Development of the Alcohol Use Disorders Identification Test (AUDIT): WHO Collaborative Project on Early Detection of Persons with Harmful Alcohol Consumption--II. , 1993, Addiction.

[12]  M. Gardner,et al.  Confidence intervals rather than P values: estimation rather than hypothesis testing. , 1986, British medical journal.