Professional Abstract

Objective

To estimate thresholds for mild, moderate, and severe levels of rheumatoid arthritis (RA) symptoms as measured by the PROMIS^® Pain Interference and Fatigue scores and to estimate changes in PROMIS scores that indicate clinically meaningful changes in symptoms based on patient and provider assessment

Study Design

Currently, researchers do not have a good understanding of how patients and providers with specific conditions, like RA, characterize their symptoms in terms of different levels of PROMIS scores. This empirical analysis sought to understand how patients and providers classify PROMIS Pain Interference and Fatigue scores and what patients and providers consider as meaningful changes in scores.

First, the research team created a series of patient vignettes describing the level of symptoms that a hypothetical patient would experience if they had a specific PROMIS score. PROMIS scores have a mean of 50 and a standard deviation of 10 in the general US population. For example, a vignette for a PROMIS fatigue score of 62 might describe a person as rarely having enough energy for strenuous exercise and often feeling too fatigued to plan for future activities. The team created one set of nine vignettes for PROMIS measures of pain interference and another for measures of fatigue.

The research team had patients and providers go through three scenarios. First, the team sorted the vignettes from least to most severe and presented the set of vignettes to the patients and providers. Patients and providers then indicated where they felt transitions between vignettes showed an increase in symptom severity (for example, from moderate to severe symptoms).

Second, patients and providers viewed another set of vignettes arranged from high to low levels of either pain or fatigue. Starting with a vignette with high symptom levels, patients and providers suggested which subsequent vignette would show that a treatment was working. Third, patients and providers viewed a vignette representing a low level of either pain or fatigue and suggested which subsequent vignette would indicate symptoms worsened so much that a change in treatment should be considered.

The research team recruited 11 patients receiving treatment for RA and eight rheumatology providers. Of the patients, six were white, three were black, one was Asian, and one was mixed race. The average age was 55. On average, patients had RA for 20 years. Providers included physicians, nurses, and psychologists. All providers were white, with an average age of 49.

Patients with RA and patient advocates helped design the study, analyze data, and interpret results.

Results

Patients varied widely in the thresholds they selected for mild, moderate, and severe symptoms; providers varied less. Patients also selected higher thresholds than providers for mild, moderate, and severe pain or fatigue.

When considering meaningful reduction in pain or fatigue, both patients and providers selected a vignette representing a 10-point change in PROMIS scores. For an increase in pain, patients selected a 10-point change, while providers suggested only a 5-point change. For an increase in fatigue, both patients and providers suggested a 5-point change.

Limitations

The study included patients who had had RA for a long time. Results might differ for patients diagnosed with RA more recently.

Conclusions and Relevance

The research team found that, compared with providers, patients differed in the level of symptoms they considered to be mild, moderate, and severe. Providers were more sensitive to changes in levels of pain interference.

Future Research Needs

Future research could include patients who have more recent diagnoses of RA to understand how these patients think about symptom severity.