Right-left discrimination among medical students: questionnaire and psychometric study

Abstract

Objective To determine medical students' self awareness and ability to discriminate right from left; to identify characteristics associated with this ability; and to identify any techniques used to aid discrimination. Design Questionnaire and psychometric study. Setting Undergraduate medical school, Northern Ireland. Participants 290 first year undergraduate students. Main outcome measure Medical students' ability to discriminate right from left using the Bergen right-left discrimination test. Results Test scores ranged from 31 to 143 on a scale of 0-144 (mean 112 (standard deviation 22.2)). Male students significantly outperformed female students (117.18 (26.96) v 110.80 (28.94)). Students who wanted to be surgeons performed significantly better than those who wanted to be general practitioners or medical doctors (119.87 (25.15) v 110.55 (27.36) v 112.50 (26.88)). The interaction effect for sex and career wishes was not significant (P=0.370). Students who used learnt techniques to help them discriminate scored significantly less than those who did not (P<0.001). Students had greater difficulty in discriminating right from left when looking at the forward view rather than the back view (P<0.001). Conclusions Male students were better than female students at distinguishing right from left, and aspiring surgeons were better than aspiring general practitioners or medical doctors. Students had more difficulty with the forward view than the back view.The ability to discriminate right from left calls on several higher functions including memory, visuospatial processing, language, integration of sensory information, and sometimes mental rotation.1 Some people have difficulty in distinguishing right from left in themselves and in others.2 3 Correctly discriminating right from left is important in the practice of medicine. Confusing a patient's right side from their left can result in surgery, procedures, and investigations being carried out on the wrong side.4 Such mistakes may occur more frequently than is reported, 4 and prevention should start at undergraduate level. 5Medical students perform better than psychology or law students in right-left discrimination tests, but data are limited. 6 We aimed to assess medical students' perceived and actual right-left discriminatory ability; to identify characteristics associated with this ability; and to identify any techniques used to aid discrimination. METHODSWe invited all first year students at the School of Medicine, Queen's University Belfast who attended a clinical skills programme to participate. Consenting students completed an anonymised questionnaire to ascertain their sex, age, and career wishes. We used the Oldfield handedness inventory to determine hand preference.7 Students recorded their perceived discriminatory ability on a five point Likert scale. We also asked them to record any techniques that they used to aid discrimination.We used the Bergen right-left discrimination test to measure participants' ability to discriminate right from left. 8 In thi...

‘Sorry, I meant the patient's left side’: impact of distraction on left-right discrimination

“…A significant proportion of our population has difficulty in distinguishing left from right . Medical students do not escape this trend, and female students and those students aspiring to become general practitioners or psychiatrists demonstrate the greatest difficulty …”

“…the hand they strum a guitar with) or an accessory feature (e.g. a wedding ring or wrist watch) . Generally, individuals who use these techniques still have difficulty in distinguishing left from right …”

Letter to the Editor: Right-left discrimination

“…6 In medicine, mechanisms can include establishing spatial congruence (with the patient) and using fixed reference (allocentric) frame(s) for orientation (http://www.nature.com/nrn/ journal/v7/n8/glossary/nrn1932.html). Affected individuals are generally aware of this difficulty and over time develop compensatory mechanisms.…”

Difficulty with right–left discrimination: A clinical problem?

“…3 Further, in a cohort of 290 medical students, more than 50% scored less than 77% on an objective right-left psychometric discrimination test. 2 Right-left discrimination is a complex neuropsychologic process that calls upon several higher functions, including visuospatial processing, memory, language and integration of sensory information, 1 and cerebral hemispherical asymmetry appears to be a contributing factor. 4 Apart from minor inconveniences, such as a delay in arrival time from taking a wrong direction in a car journey, the impact of laterality errors is often negligible.…”

“…For many, right-left discrimination is second nature, but for a substantial proportion of our population, distinguishing right from left is difficult. 1,2 In a cohort of nearly 800 adults, about 9% of men and 17% of women selfreported difficulty in distinguishing right from left. 3 Further, in a cohort of 290 medical students, more than 50% scored less than 77% on an objective right-left psychometric discrimination test.…”