Study: Patient Global Assessment Scores Give Insight Into Daily Function

Nuad Contributor / shutterstock.com

A recent article in Arthritis Care & Research supports the idea that the patient global assessment reflects primarily the patient’s experience of their functioning in daily life.¹

Background

The patient global assessment is a key measure used by clinicians and researchers to help evaluate disease status in rheuma­toid arthritis (RA). Lead author Ethan T. Craig, MD, MHS, an assistant professor of clinical medicine at the University of Pennsylvania, Philadelphia, and associate editor of The Rheumatologist, explains, “It’s there to capture a gestalt of the patient’s experience of how things are going.”

The patient global assessment is a component of many different disease activity scores used to assess treatment goals in RA, including the CDAI (Clinical Disease Activity Index), the RAPID3 (Routine Assessment of Patient Index Data) and the DAS28 (28-joint count Disease Activity Score).²

The patient global assessment is given as a single question, scored from 0–10 or 0–100, with higher numbers representing worse perceived disease activity or overall health. The non-standardized question can be phrased in terms of global health or overall disease activity.² “Depending on how you formulate that question,” notes Dr. Craig, “you may get different responses.”

One strength of the patient global assessment is that it provides a lot of basic information in one number. “But one of its limitations is assessing what exactly is being communicated to us,” says Dr. Craig. “When a patient tells me their score is 10 on a scale of 0–10, does that indicate they are having a lot of pain? Does that indicate they are not functioning well? Does it indicate they are very fatigued? It’s a key question: What aspects of experience are patients drawing on when they report a global assessment?”

Dr. Craig initially became interested in studying the patient global assessment to explore the question of discordance—when patients’ assessments don’t correspond with the rest of the data, as assessed by the clinician. “We know from previous studies that the patient global assessment is the most common parameter to impact attainment of remission in the Boolean-based remission criteria,” he says. Some researchers have even proposed removing the patient global assessment from these remission criteria and focusing on such data as swollen joint counts and C-reactive protein levels.³

Dr. Craig notes that pain has reliably been found to be associated with the patient global assessment. To some extent, physical function and fatigue have shown this association as well. “The piece that has been a little more controversial has been the role of anxiety and depression,” he says.

Although patient global assessment scores tend to track with physician-assessed measures of disease activity, some studies have indicated they are also associated with other components of health, such as mental health comorbidities. Dr. Craig adds, “I think there is a sense that when the patient global assessment doesn’t track well with physician assessments or with RA activity scores, that it may reflect anxiety or depression.”