Right and left-handedness and medical speciality choice
in a large prospective study of medical students and doctors
I C McManus
Hallgeir Jonvik
Research Department of Clinical, Educational and Health Psychology
University College London
Gower Street
London WC1E 6BT, UK
The 1991 cohort comprises 6902 individuals who in the autumn of 1990 applied for
admission to one of five English medical schools (St. Marys, UMDS, UCMSM, Sheffield and
Newcastle) 1. Questionnaires were sent to all of those with EU postal addresses, of whom
5146 replied. 3333 individuals were accepted for medical school, and they have
subsequently been followed up, in various ways, in their final year at medical school 2;3, as
PRHOs 4, and in 2002/2003 5. A further follow-up is currently being organised for the
beginning of 2009, as a part of which individuals were identified on the General Medical
Council's List of Registered Medical Practitioners (LRMP), and in particular membership of
the Specialist Register and the GP Register was ascertained1. All of the questionnaires used
in the various studies, along with other information about the cohort, can be found at our
website at www.ucl.ac.uk/medical-education/medical-education-studies/1991cohort.
Assessment of handedness.
Handedness was ascertained in the study of applicants using a single question in the survey
of applicants:
"Q.56: Which hand do you write with? Always Right / Usually Right / Either /
Usually Left / Always Left".
Of 5146 applicants, 4457 (86.6%) replied Always Right, 179 (3.5%) Usually Right, 12
(0.2%) Either, 32 (0.6%) Usually Left, and 466 (6.8%) replied Always Left. Following the
convention of many studies of lateralisation, we classified Either, Usually Left and Always
Left as Left-handers and Usually Right and Always Right as Right-handers. Overall 9.9%
1
Comparison of the doctors from the earlier 1986 cohort, and an assessment of the date at which
individuals went on to the Specialist and GP Registers, suggests that although most career GPs in the 1991 cohort
would be on the GP Register by 2008, only about half of those in the 1991 cohort who would eventually be on the
Specialist Register would have been on it by 2008.
1
(510/5146) medical school applicants were left-handed. Analyses reported elsewhere have
found that in this study the rate of left-handers, as in many other studies, was somewhat
lower in females and in applicants from ethnic minorities 6.
Assessment of career interest or speciality choice.
Interest in a career in a range of different medical specialities was assessed in different ways
at different parts of the survey.
Applicants. Question 43 presented a list of 27 medical specialities, with applicants stating for
each whether they had a "Definite intention to go into it", they found it "Very attractive",
"Moderately attractive" of "Not very attractive", or had a "Definite intention not to go into
it". Interest in surgery overall was calculated as the highest rating given to any of "Surgery
(including neurosurgery, thoracic surgery, etc)","Traumatic and Orthopaedic Surgery", and
"Ear, Nose, Throat Surgery".
Final year students. Question 27 used a very similar question to that used in the applicants
survey, with the addition of a single extra non-surgical speciality. Scoring was as for the
applicants survey.
PRHOs. Q.13 used the same question to that used in the final year survey, and scoring was
also the same.
2002 follow-up. Two separate measures of speciality choice were available in this study.
a) Attractiveness of specialities. In the 2002 follow-up it was not possible as in the
earlier surveys to ask about the specialities "as a possible career", as many but far
from all doctors had chosen their specialities. Q.7 therefore asked, "How attractive
would be each of these broad areas of medical practice to you as a career?", followed
by the eleven categories used by the Department of Health, with the addition of
Research.
b) Current post. Q.1 asked about the current medical post and answers were classified
into the same categories as those used in Q.7, with an additional category of 'Other'.
2008 follow-up. The 2008 follow-up, which was in preparation for a questionnaire survey in
2009, assessed whether doctors were currently on the GMC's List of Registered Medical
Practitioners, and if so, whether they were on the Specialist Register or the GP Register.
Doctors were classified as surgeons if the word was used in any of their entries on the
Specialist Register.
2
Handedness and Speciality Choice.
Table 1 below shows how handedness relates to speciality choice and speciality at various
career points. There was no relationship between being left-handed and an interest in surgery
at application, in the final year, as a PRHO, or in 2002/3. Table 2 shows the speciality of the
current post in 2002/3, and there is no association with handedness in general, or in particular
comparing surgeons with others. In the 2008 follow-up, only 25 of 2677 doctors were on the
Specialist Register as a surgeon, and of these 3 (12.0%) were left-handed, compared with
10.4% of left-handers (276/2652) amongst the other doctors, a non-significant difference
(chi-square = 0.067, 1 df, p= .795).
Conclusions.
Rates of left-handedness amongst medical students and doctors are similar to those in the
population in general. There was no evidence of any association of left-handedness either
within medical students of wanting to become a surgeon, or in qualified doctors of working
within surgery or going onto the specialist register.
Acknowledgments. We are very grateful to Professor Lis Paice for her continuing support of
this and other longitudinal studies.
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Reference List
(1)
McManus IC, Richards P, Winder BC, Sproston KA, Styles V. Medical school applicants from ethnic
minorities: identifying if and when they are disadvantaged. British Medical Journal 1995; 310:496-500.
(2)
McManus IC, Richards P, Winder BC. Intercalated degrees, learning styles, and career preferences:
prospective longitudinal study of UK medical students. British Medical Journal 1999; 319:542-546.
(3)
Petrides KV, McManus IC. Mapping medical careers: Questionnaire assessment of career preferences in
medical school applicants and final year students. BMC Medical Education 2004; 4:18.
(4)
McManus IC, Winder BC, Paice E. How consultants, hospitals, trusts and deaneries affect pre-registration
house officer posts: a multilevel model. Medical Education 2002; 36:35-44.
(5)
McManus IC, Keeling A, Paice E. Stress, burnout and doctors' attitudes to work are determined by
personality and learning style: A twelve year longitudinal study of UK medical graduates. BMC Medicine 2004;
2:29.
(6)
McManus IC. The history and geography of human handedness. In: Sommer I, Khan RS, editors.
Language lateralisation and psychosis. Cambridge: Cambridge University Press; 2009. 37-58.
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Table 1. Handedness of medical students and doctors in relation to interest in a surgical career.
- - - - - - - - - - - - - - - - - - - - - - -Percentage of left-handers - - - - - - - - - - - - - - - - - - - - - - Interest in Surgery as
a career
Applicants
Final year students
PRHOs
Definite intention to
go into it
9.9%
(58/588)
10.8%
(11/102)
13.9%
(21/151)
Extremely attractive
Very attractive
9.6%
(253/2624)
13.2%
(45/341)
9.0%
(20/221)
Very attractive
Moderately attractive
10.4%
(140/1341)
7.6%
(27/355)
11.8%
(28/238)
Moderately attractive
11.7%
(21/159)
11.4%
(40/350)
8.0%
(21/263)
9.5%
(23/241)
Fairly unattractive
9.4%
(31/329)
5.8%
(5/86)
10.4%
(28/269)
9.7%
(40/412)
Very unattractive
11.4%
(81/712)
9.9%
(496/4989)
9.9%
(132/1198)
10.5%
(132/1131)
Chi-square
3.14, p=.535
7.481, p=.113
3.284, p=.511
Chi-square
1.322, p=.858
Linear trend
0.151, p=.698
1.302, p=.254
1.053, p=.305
Linear trend
0.278, p=.598
Not very attractive
Definite intention not
to go into it
Total
2002/3 follow-up
Total
10.1%
(21/207)
9.4%
(9/96)
10.7%
(163/1524)
Table 2: Speciality of current post in 2002/3 follow-up in relation to handedness.
Speciality
% Left-handers
Anaesthetics
12.2% (16/131)
General Practice
11.3% (56/497)
Hospital Medicine
9.2% (24/261)
Obstetrics and Gynaecology
4.0% (2/50)
Pathology
9.8% (4/41)
Paediatrics
11.8% (12/102)
Psychiatry
9.4% (9/96 )
Public Health
30.0% (3/10)
Radiology/Radiotherapy
13.3% (6/45)
Research
0% (0/2)
Surgery
9.0% (24/242)
Other
10.0% (1/10)
Total
10.4% (157/1511)
Chi-square (overall)
9.119, 11df, p=.611
Surgery vs Others, Chisquare
0.649, 1 df, p=.421