A personal view published on bmj.com asks if patients can trust doctors who have ties with medical companies.

Emergency Physician Leana Wen, from George Washington University in the US, says that doctors should fully disclose any conflicts of interest to patients in order to build on patient trust. She says that due to her campaigning, she has become an "object of hatred".

A recent study showed that "94% of American doctors have some relationship with a drug or medical device company" with other studies showing that these associations "skew research findings and doctors' prescribing practices". Wen says that doctors are expected to disclose this information to each other but not to patients, even though it is patients that are most affected.

She says doctors' salaries often depend on the number of tests they order and procedures they perform with the Institute of Medicine estimating that "30% of all tests and treatments done are unnecessary, to the tune of $750bn every year".

Wen asks whether "tests are being prescribed because it's in [patients] best interest or because they benefit the doctor?".

Research has shown that openness leads to more trust and better relationships, improved patient-physician communication and patient adherence to treatment recommendations.

Wen has met with conflict with other doctors saying that patients "can't handle the truth". But she believes it "should be up to patients to decide what is relevant to them when choosing a doctor and whether to follow that [...] recommendation".

She says that much more needs to be done and that "establishing trust is a critical part of care" and "at the core of what it means to be a doctor".

She concludes that it should be compulsory for doctors to disclose how personal incentives could affect treatment and that her patients' responses prove this, with one telling her "If you're willing to be so vulnerable with me, I know I can trust you".