Observers’ Pain Catastrophization Affects Pain Estimates, Contextual Information Improves Estimates

When some people experience pain, particularly chronic pain, they can catastrophize the pain, believing that everything can and will get worse than it is. Many researchers have looked into this behavior in an attempt to discover just how it affects pain and healing. Research is also being done into how others see, or perceive, the pain being experienced by someone else. Understanding the perception of pain would result in better patient assessments.

Earlier research has found that the person who is observing the pain and interpreting it will base their perception on the sex of the person in pain, in addition to how he or she is behaving. As well, the sex of the person observing plays a role. However, not much research has been done into how this affects the perception.

The authors of this article wrote that studies have focused on asking observers what level of pain they thought patients had, based on their behaviors. These types of studies do not seem to be all that accurate because many of the observers were not correct. To work on how to improve this type of research, in one study, Sullivan and colleagues showed that catastrophic thinking could lead to a higher estimation of pain estimates among observers.

For this study, the authors built on Sullivan’s findings and examined how observers perceived the reactions of others as they underwent a physically demanding lifting task. This was done by using different variations in how the subjects reacted to the task and the observers were then asked to rate what type of pain the subjects were feeling.

A group of 98 healthy subjects (79 women) participated in this study. The subjects watched videos of people who had chronic back pain and were lifting various weighted canisters. In an earlier study, the patients in the videos had been asked to rate their pain as they did these tasks. In the videos, the patients were lifting the canisters in different ways. The easy way was lifting close to the body with the elbows bent at a 90 degree angle. The difficult way was lifting with the canister as far away from the body as possible, with the arms fully extended. The observers could see the patients’ face, upper body and arms. Before watching the videos, the observers were assessed regarding their own ideas of pain and whether they catastrophized pain, using the Pain Catastrophizing Scale (PCS). This scale uses 13 items that described different thoughts associated with the pain. The study participants were asked to think about their own experiences regarding pain and how much pain they thought that the patients were experiencing, using all 13 items and a five-point scale for each. Zero on the scale meant “not at all” and then moved up by points until it reached “all the time.”

After the experiment was complete, the researchers compiled the data and found that the observers rated a higher pain load when the patients were lifting with the canisters away from the body. The researchers also found that the women were rated by the observers as having more intense pain than the men. The sex of the observer didn’t make any difference in pain observations but observers who catastrophized, according to the testing before the videos, were more likely to rate the pain of the people in the video as being higher than those who did not catastrophize. Contextual information, such when the patients lifted the canisters with their arms extended, did play a role too. In fact, when the observers used the contextual information, they more accurately assessed the patients’ pain levels.

The authors discussed the findings and wrote that although previous studies have found that there are differences in pain perception according to sex, the results of this study showed that the sex of the patient is what made a difference in determining how much pain the person may have been experiencing, not the sex of the observer. There was also the perception that if the task looked painful or difficult (lifting the canister away from the body), then the observers would rate the subjects’ pain as being higher. When the subjects didn’t display any signs of pain at all (in body posture or facial expressions), the difficulty of the task and their sex was still apparent in judging pain level.

When the researchers looked at pain behaviors displayed by the subjects, they found that this only made a 9 percent difference with the observers. But, in other studies, this made up to 36 percent.

Information like this is important to healthcare professionals. As researchers learn more about how people perceive the pain of others, they will become more accurate in their assessments if they have the proper tools. Knowing that contextual information leads to more accurate assessments, this should be taken into account when working with patients who have chronic pain.