I was greatly concerned to read last Saturday's report ("Complaints against doctors at all-time high"), particularly the part about complaints of over- or unnecessary treatment and misdiagnosis.

What is perceived as "over- or unnecessary treatment" and "misdiagnosis" is often irreconcilable in medicine.

For instance, regular screening mammography is encouraged by the local health authorities.

But 10 out of 11 women will not get breast cancer. Would the mammogram then be a case of overtreatment?

On the flip side, if screening is not performed, one in 11 women would have a delayed diagnosis of breast cancer, affecting her survival benefit.

Would this non-screening approach then be a case for complaint?

Doctors face constant and difficult judgment calls as to whether to perform additional tests - which can be perceived as unnecessary treatment - or not to perform more tests, and risk missing a timely diagnosis of a rare medical condition.

This is the great conundrum of medicine.

Doctors are neither omniscient nor prescient. We gather information from the patient, tests and prior clinical studies to institute a treatment plan, based on the high probability of making the correct diagnosis.

But there are limitations to this approach because a minority of patients do not fit the expected pattern.

Patients often seek redress by taking legal action against their doctors. This naturally results in higher indemnity costs for doctors.

We have seen the ultimate outcome of a low threshold for litigation - fewer doctors willing to assist patients because of unrealistic expectations and a lack of appreciation for the limitations and pressures doctors face ("Looming shortage of doctors to deliver babies"; Feb 18).

It is my earnest wish, as a clinician, that as the public becomes better educated, they will also become more enlightened.

Mona Tan (Dr)