The language barrier is an extremely difficult and sensitive situation to broach, especially when the question on consent comes into play.
When you do not speak the same language to your patient, there is always a level of uncertainty on whether your patient- not the family member or friend accompanying the patient- actually understands what you are talking about. It is an instant barrier between you and your patient, and in my own personal experience, I can never be 100% sure whether my patient actually understood my true message after it has been translated. Proceeding with a procedure requires the full understanding of the risks and benefits. It takes quite a bit of explaining and time for someone who speaks your same language to make an informed decision, let alone someone who may lose the essential message through translation into a different language. This can be problematic as patients may sign a form and not have his/her expectations answered prior to the procedure, which could have changed their decision making process. Each doctor consenting a patient needs to assess the capacity of a patient, and is made more difficult by the barrier in communication, requiring a middle man in someone who doesn't speak the same language as the doctor. There is always a small level of uncertainty that even if a translator gives the doctor the answer that confirms capacity of the patient, it is never as clear as it would for the doctor to actually understand the words first hand from the patient him/herself.
On addressing the question of family members and that they had "done their homework", it would be comparable to the simple concept that doctors are not recommended to be the primary doctor of their own family members. It is extremely important to ensure there is no potential bias or conflict of interest for any patient making a decision, followed by the importance of keeping patient confidentiality- which in some cases involves not telling the family members. Doctors should not be treating their own family, and albite family obviously are and ask all the questions they deem important, it is essential for the primary physician to obtain an unbiased assessment of the patient. As is pointed out by another rapid response below, our true messages may be lost in translation unintentionally or intentionally; so unless you yourself are speaking directly to the patient, there is no guaranteed your full message has been sent through. It is important to make sure- in the picture of consent- that it is the patient signing the consent, not the family member/ translator's influence.
The only way that we can ensure that the patient is given the fairest chance to make an informed decision about treatment is to remove the element of confusion and bias by consenting through an official translator that is trained professionally to communicate complex medical terms to the patient in the language of choice. Not utilising family members or personal friends is not in any way "unappreciative" or "disregarding" the effort they have put into the welfare of the patient, but an important part of medical practice to ensure the patient is getting the best unbiased care provided without extra barriers, as would someone who speaks the same language as the doctor.
Competing interests: No competing interests