More patients need to allow medical students to help provide their care in order to safeguard doctors' training, researchers have said.
Students practise techniques on dummies before they see patients
The Birmingham University team warned patients were increasingly refusing to allow students to carry out procedures.
In the Journal of Medical Ethics, they said doctors may be qualifying with gaps in their knowledge as a result.
The Patients Association said patients were keen to help but often questions were not put to them in the right way.
The researchers said there needed to be a culture where refusal to allow a student to carry out a medical procedure was rare.
They said patients were most likely to refuse to allow students to carry out intimate medical examinations.
At the moment, patients have to give explicit permission before medical students are allowed to become involved in their treatment or care.
The researchers said this should be replaced by a system that starts with the premise that there is no reason why students who are competent in carrying out a procedure, such as taking a blood sample, should not be doing so.
Patients would retain the right to opt out, but allowing a student to participate in care would become the norm, they said.
Prior to being allowed to practise on patients, students would be assessed in a simulated setting, either practising on dummies or actors taking the place of patients.
Once they had passed this stage and been seen to carry out a procedure effectively on a patient, they would be allowed to carry on doing so without supervision.
Jim Parle, professor of general practice at Birmingham University and one of the researchers, said: "Patients rightly want to know that their treatment is being conducted by someone with the relevant skills.
"As long as students have received adequate training, they should be given the opportunity to engage in procedures.
"In the end it is not in the interests of patients to exclude medical students from consultations, as this is likely to lead to poorer doctors in the future."
Vanessa Bourne, of the Patients Association, said: "It is true that patients are increasingly saying 'no'.
"It's not that they don't want to help, but something is going wrong in the way the question is asked.
"Doctors need to sort that out, rather than changing the rules."
She added: "Medical schools have no set rule for communication training - it is up to each one. But it is absolutely essential that communication skills are the best they can be."