Wrong information on previous studies of the clinical use of placebo
In their paper on the clinical use of placebo Nitzan and Lichtenberg
claim that ‘No study has recently attempted to assess the use of placebos
in clinical settings’ (1). This information is prominently featured in the
box entitled ‘What is already known on this topic’. Furthermore, the
article discusses only one previous study by Goodwin et al. published in
1979 (2).
However, the article’s information on previous studies is wrong. In
June 2003 we published a large study on the clinical use of placebo and
the attitude to placebo interventions in a national cohort of 772 randomly
sampled Danish doctors. Furthermore, at least five additional studies on
the clinical use of placebo has been conducted since 1979 (4-8); one in
1999 (4), and one in 1997 (5).
If the authors had conducted simple PubMed searches they would have
identified five of the six studies published since 1979 (3,4,6-8). A
‘Related Articles’ search, based only on the Goodwin publication, would
have identified four studies (3,4,7,8).
It is reasonable to expect authors to identify and comment on
previous studies, enabling readers to put new findings into context and to
assess the originality of the research.
1) Nitzan U, Lichtenberg P. Questionnaire survey on use of placebo.
BMJ doi:10.1136/bmj.38236.646678.55
2) Goodwin JS, Goodwin JM, Vogel AV. Knowledge and use of placebo by
house officers and nurses. Ann Intern Med 1979;91:106-10.
3) Hróbjartsson A, Norup M. The use of placebo interventions in
medical practice - a national questionnaire survey of Danish clinicians.
Eval Health Prof 2003;26:153-65.
4) Berger JT. Placebo medication use in patient care: a survey of
medical interns. West J Med 1999;170:93-6.
5) Ernst E, Abbot NC. Placebos in clinical practice: results of a
survey of nurses. Perfusion 1997;10:128-130.
6) Thomson RJ, Buchanan WJ. Placebos and general practice: attitudes
to, and the use of, the placebo effect. N Z Med J 1982; 95:492-4.
7) Lynøe N, Mattsson B, Sandlund M. The attitudes of patients and
physicians towards placebo treatment - a comparative study. Soc Sci Med
1993;36:767-74.
8) Gray G, Flynn, P. A survey of placebo use in a general hospital.
General Hospital Psychiatry 1981;3:199-203.
Competing interests:
None declared
Competing interests:
No competing interests
20 September 2004
Asbjørn Hróbjartsson
Senior researcher
The Nordic Cochrane Centre, H:S Rigshospitalet, DK-2100 Copenhagen Ø, Denmark
Rapid Response:
Wrong information on previous studies of the clinical use of placebo
In their paper on the clinical use of placebo Nitzan and Lichtenberg
claim that ‘No study has recently attempted to assess the use of placebos
in clinical settings’ (1). This information is prominently featured in the
box entitled ‘What is already known on this topic’. Furthermore, the
article discusses only one previous study by Goodwin et al. published in
1979 (2).
However, the article’s information on previous studies is wrong. In
June 2003 we published a large study on the clinical use of placebo and
the attitude to placebo interventions in a national cohort of 772 randomly
sampled Danish doctors. Furthermore, at least five additional studies on
the clinical use of placebo has been conducted since 1979 (4-8); one in
1999 (4), and one in 1997 (5).
If the authors had conducted simple PubMed searches they would have
identified five of the six studies published since 1979 (3,4,6-8). A
‘Related Articles’ search, based only on the Goodwin publication, would
have identified four studies (3,4,7,8).
It is reasonable to expect authors to identify and comment on
previous studies, enabling readers to put new findings into context and to
assess the originality of the research.
1) Nitzan U, Lichtenberg P. Questionnaire survey on use of placebo.
BMJ doi:10.1136/bmj.38236.646678.55
2) Goodwin JS, Goodwin JM, Vogel AV. Knowledge and use of placebo by
house officers and nurses. Ann Intern Med 1979;91:106-10.
3) Hróbjartsson A, Norup M. The use of placebo interventions in
medical practice - a national questionnaire survey of Danish clinicians.
Eval Health Prof 2003;26:153-65.
4) Berger JT. Placebo medication use in patient care: a survey of
medical interns. West J Med 1999;170:93-6.
5) Ernst E, Abbot NC. Placebos in clinical practice: results of a
survey of nurses. Perfusion 1997;10:128-130.
6) Thomson RJ, Buchanan WJ. Placebos and general practice: attitudes
to, and the use of, the placebo effect. N Z Med J 1982; 95:492-4.
7) Lynøe N, Mattsson B, Sandlund M. The attitudes of patients and
physicians towards placebo treatment - a comparative study. Soc Sci Med
1993;36:767-74.
8) Gray G, Flynn, P. A survey of placebo use in a general hospital.
General Hospital Psychiatry 1981;3:199-203.
Competing interests:
None declared
Competing interests: No competing interests