VANCOUVER - A spoon full of sugar helps the medicine go down, but patients feeling aches and pains can wind up with a remedy more like cod liver oil if they're not on good terms with their doctor.

A University of Northern B.C. professor who is studying the impact of the clinician-patient relationship on how health professionals rate pain suggests it decreases if the clinician doesn't like the patient.

Pain sufferers often take issue with their treatment, which is why the research is so important, said psychology professor and pain expert Ken Prkachin.

"A specific complaint being 'Nobody believes me, no one is taking me seriously,"' Prkachin described in an interview.

"You really get that sense when you talk to patients, maybe people are being downgraded because they're also disliked."

It means people with invisible pain -- such as bad backs, as opposed to broken legs -- may not get adequate treatment for the problem if the doctor disregards their feelings, he said.

"A good case can be made ... that is going to demoralize patients and contribute to very testy patient-professional relationships," Prkachin said.

"What we're trying to do is understand what's going on there and how to change that."

The research, presented in an article co-written by Prkachin and five other researchers from the University of Ghent in Belgium, was published in the latest edition of the international journal Pain.

The team combined a new study, completed last spring, with other findings to develop the theory that while the average person underestimates pain in someone they dislike, health professionals reduce its severity even further.

To arrive at that hypothesis, the team showed study participants photos of patients connected with positive, neutral and negative personality traits. Next, participants viewed videos of the same patients in moderate, severe and no pain.

The participants consistently rated the pain of patients associated with the negative traits, such as egotism and hostility, lower than the likable patients.

"When you associate dislikability with a person, it's like you change an observer's perception such that they just don't pay close attention to (the person's pain-related) behaviour any more," Prkachin explained.

Health professionals, who deal with pain on a daily basis, are likely more desensitized to pain due to overexposure, he added.

Serious study should be undertaken into the long-term consequences of misreading the severity of a patient's pain, he said. Potential ramifications are that people won't get the care they require, or they won't follow the clinician's treatment prescriptions seriously, and therefore continue to suffer.

"Not getting the adequate or appropriate treatment is, in principle, harmful in itself," he said.

Remedying the situation could be as simple as urging clinicians to set aside their negative feelings and attempting to boost their empathy, he said.

"The simple act of encouraging perspective taking -- to try to look at it from the other person's point of view, to get in the person's head and understand what's happening to them," Prkachin said, could almost eliminate the bias.

The team has also shared its research at several health symposiums in Montreal.