Published: May 13, 2013
By Elizabeth DeVita Raeburn , Contributing Writer, MedPage Today

Action Points
Asking three simple questions of patients with non-inflammatory musculoskeletal pain improved primary care physicians’ ability to predict which patients would still be in pain 6 months later, a study found.
Note that the three relevant prognostic indicators were duration of present pain episode, pain interference with daily activities, and presence of multiple-site pain.

Asking three simple questions of patients with non-inflammatory musculoskeletal pain improved primary care physicians’ ability to predict which patients would still be in pain 6 months later, a study found.

The questions — combined with a normal work-up — proved to be a more accurate predictor of persistent pain than work-up alone (C statistic 0.72 versus 0.62, net reclassification index 0.136, proportion correctly classified 69%), Christian D. Mallen, PhD, of Keele University in Staffordshire, England, and co-authors wrote online May 13 in JAMA Internal Medicine.

Previous studies have suggested that physicians treating patients with musculoskeletal pain tend to be overly optimistic, because they think an upbeat attitude will help their patients, the authors wrote. The improved prognostic accuracy seen in the current study, they said, was likely due to correcting physicians’ “over-optimistic expectations.”

Musculoskeletal conditions are the cause of 20% to 30% of primary care consultations, the researchers noted. But “there are no accepted clinically meaningful decision thresholds for common musculoskeletal pain that could guide targeted management, and no information to date about the associated costs of doing so.”

To explore the issue further, the investigators undertook a prospective, observational cohort study, known as the Prognosis Research Strategy (PROG-RES). The study included 402 patients age 50 or older with musculoskeletal pain, of whom 48.1% were determined to have an “unfavorable outcome” — defined as the same, worse, or much worse discomfort — at a 6-month follow-up.

The three questions the physicians asked were:

• When was the last time you were free of pain for a month or more?
• In the last month, has this pain interfered with your daily activities?
• Have you had pain anywhere else in the last month?

Two other questions were also tested in the study:

• How would you rate your pain on a 0-to-10-point scale?
• During the past month, have you often been bothered by feeling down, depressed or hopeless, or had little interest or pleasure in doing things?

Data analysis, however, showed that those two questions didn’t add to the accuracy of the model, the investigators wrote.

The study “sets a high standard for clinical relevance by integrating brief assessment into the clinical encounter while combining physician prognostic judgment and patient-reported information to predict long-term pain outcomes,” wrote Michael Von Korff, ScD, of the Group Health Research Institute in Seattle, in an accompanying editorial.

The use of these questions with a wide variety of pain represents a departure from earlier studies, the authors noted. Most such studies use site-specific questions for the back, shoulder or knee, an approach that is impractical in routine practice where “single-site musculoskeletal pain is the exception rather than the rule.”

There were several limitations in the study. “Our decision to categorize several indicators despite being made before data analysis and using recognized cut points, resulted in a loss of information,” wrote the authors. They also did not examine the relationship between the site of pain and how well the model performed.

“A possible next step,” wrote Korff, “would be to determine whether site-specific prognostic assessments sustain comparable predictive validity when used to predict outcomes for diverse patients with musculoskeletal pain.”