In my last article, I highlighted how a placebo response can be influential in the reduction of pain. In this one, I want to highlight another recent article written by Joel Bialosky on how individual expectation is influential in the clinical outcomes of treating musculoskeletal pain.
When someone goes to the doctor, they have an expectation that the doctor will make a diagnosis and will treat that disorder. They hold a general belief that a clinical outcome will occur. These expectations can be positive or negative and can be influenced on past experiences.
Bialosky et al cites Thompson and Sunol who have developed a model of expectation to help us understand the types of expectations and how they relate to patients we may see.
- Predicted Expectations: what an individual thinks will occur.
- Ideal Expectations: what the individual wants to occur.
- Normative Expectations: what the individual believes should occur.
- Unformed Expectations: expectations which an individual is unaware or is unwilling or unable to express.
Previous studies have associated a link between predicted expectations and outcomes in the treatment of many different conditions which provoke musculoskeletal pain. For example, they correlate predicted expectations for pain relief and low risk of complications following joint arthroplasties. When a surgeon consults with an individual prior to a knee replacement, the surgeon generally gives the patient a visual of “their problem” via xray and explains the procedure as “cutting out the problem”. This allows predicted expectations to form in which the individual believes that they will have better outcomes following the procedure.
Where predicted expectations can have a positive influence, they may also act as a confounding variable in studies using a placebo. For example, an article by Linde et al looked at the efficacy of acupuncture in relation to placebo acupuncture. The authors found that outcomes did not depend on the interventions applied but instead on the expectations that they would have pain relief with acupuncture. This result relates back to my placebo article review. The intervention may have been placebo, but the expectations as well as other environmental and deamener variables may have influenced outcomes.
Overall, as PTs we need to create realistic, positive expectations for our patients. We should not focus on the negative aspects of a condition but instead on the positive, realistic-outcomes that the individual may have following our interventions.
Bialosky JE, Bishop MD, Cleland JA. Individual Expectation: An Overlooked, but Pertinent, Factor in the Treatment of Individuals Experiencing Musculoskeletal Pain. Physical Therapy 2010; 90: 1245-1255.