Intended for healthcare professionals

Rapid response to:


Honesty about new screening programmes is best policy

BMJ 2000; 320 doi: (Published 25 March 2000) Cite this as: BMJ 2000;320:872

Rapid Response:

Women, Informed Consent and Cervical screening

Doctors no longer have any choice in the matter of informed consent -
the GMC has spelt out their responsibilities. Last year the General
Medical Council has sent every doctor on its register a copy of Seeking
patients consent: the ethical considerations. If you have misplaced your
copy you can obtain another from http://www.gmc-
. Amongst other things this guidance
states that a doctor must obtain informed consent from a patient before he
performs a non-emergency test.

What is informed consent? There are three components to informed

1. Information

2. Comprehension

3. Voluntariness.

Let us see how these principles apply when a woman visits her GP for a
routine NHS Cervical Screening program (NHSCSP) Pap smear.


The guidance makes it quite clear that at a minimum, The GP must inform
the woman of the benefit she will get by submitting to the test. The
benefit is calculated quite simply. It is the difference between the
woman's prognosis if she does or doesn't have the Pap smear. So what
should he tell her, how great is this benefit? Surprisingly even after
searching the literature and speaking to experts, we could find not find
out. We suspect that few doctors reading this journal know either. If
this is so it means that most women are not giving informed consent to
cervical smear examinations! To rectify this lack of knowledge we have
calculated the benefit of a patient attending the NHSCSP and present our
findings in the table attached. The table gives a clear visual indication
of the chance of a woman surviving for 10 years if she does - or doesn't -
have her routine Pap smears. It is apparent that to an individual woman
the absolute benefit of having a Pap smear is small.

Table 1 - to show the benefit gained by women attending the NHS 
cervical cancer-screening programme 
Age           No of         Alive 10         Alive 10
at start      women alive   years later      years later
of 10         at start of   if they attend   if they do 
year period   10 year       NHSCSP           not attend
              period                         NHSCSP 
25           10,000         9963              9962
35           10,000         9863              9859
45           10,000         9713              9708
55           10,000         9457              9450

Women must also be told about the inaccuracy of the Pap test and
the disadvantages of being tested. For instance, they must be told that
it is quite likely that the laboratories that examine her smear will quite
likely miss abnormalities if they are present. We suggest that a
statement suggesting that "even in the best laboratories, at least 5-15%
of abnormal smears may be reported as normal", is appropriate. They should
also be told that there is about a 7% chance that they will require
further testing and about a 3% chance that they will need to attend a
hospital and undergo colposcopy.

2) Comprehension.

A doctor should never perform an elective test, such as
a Pap smear, if there is any doubt of the woman's ability to understand
its significance. The rule is that a patient must consciously opt into
testing. A doctor must not make a decision on behalf of the woman - no
matter how well intentioned - unless she asks him to do so. If he does
make a decision on her behalf he must inform her of any potential conflict
of interest.

3) Voluntariness - potential conflict of interest.

The GMC states that if
a doctor has a financial interest in recommending a test then he must
inform the patient of a potential conflict in interest. Now it is a fact
that GPs typically earns hundreds or thousands of pounds a year by
performing smear examinations. Therefore it is quite clear that a GP
should tell a woman attending for Pap smear of this potential conflict of


In order to obtain informed consent, GPs should at a minimum:

1. Inform women of the absolute benefit of their participation in the
cervical screening programme. The benefit to an individual woman of
attending the NHSCSP is extremely small.

2. Inform women of the inaccuracy of the test and disadvantages of being

3. Always make sure that women understand what they have been told

4. Inform women that because the Health Authority pays them to perform Pap
smears that there may be a conflict of interest.

5. Familiarise themselves with the GMC's booklet: Seeking patients
consent: the ethical considerations.

An article based on data presented in the table in this letter
appeared in Pulse (13 May. 2000)

Andrew Rouse & Tom Marshall

Department of Public Health and Epidemiology,
University of Birmingham , Edgbaston, Birmingham, B15 2TT

e-mail: or e-mail:

Competing interests: Table 1 - to show the benefit gained by women attending the NHS cervical cancer-screening programme ________________________________________________________Age No of Alive 10 Alive 10at start women alive years later years laterof 10 at start of if they attend if they do year period 10 year NHSCSP not attend period NHSCSP _______________________________________________________25 10,000 9963 996235 10,000 9863 985945 10,000 9713 970855 10,000 9457 9450______________________________________________________

03 July 2000
Andrew Rouse
Senior Lecturer, Dept of Public Health
Birmingham university