In the UK, medical students are 4.5 to 7.2 times more likely to come from the wealthier socio-economic groups 1-3 than 4-7, write Professor Terence Stephenson, president of the Royal College of Paediatrics and Child Health, and Lucy Stephenson, a medical student.
Selection to a medical course should not depend on the applicants' financial status. However, with "grade inflation" at A level, choosing between applicants can involve other criteria that may depend on ability to pay, they say.
They calculate that the activities required as part of the selection process for many medical courses comes to over £1,600.
The costs include travel to attend UKCAT and BMAT exams, and a residential course to familiarise applicants with the medical career and the complex application process, and to have interview coaching and guidance.
It also includes the cost of attending six open days, as far afield as Exeter and Edinburgh, and an average of two interviews, usually accompanied by one or both parents. If offered a place, students may also pay for vaccinations essential to commencing the course.
Adding all these costs together comes to £1609.60, they say.
But this figure doesn't include non-academic activities, such as music, sport, or work experience that can also influence whether an applicant is offered a place, but that often require significant financial assistance over many years.
They also point out that a school pupil from a poor background may have a part-time job evenings and weekends in addition to their four A level subjects competing for their time and resources.
They conclude: "In addition to the greater opportunity that professional parents have to arrange appropriate work experience, and the lesser debt aversion of wealthier families (medical students finish the course with average debts of £35,000), the costs described here may further disadvantage young people from poorer backgrounds in the process of selection for medical school."