Original Contributions Can Patients Accurately Read a Visual Analog Pain Scale? DAVID SALO, MD, PHD,* DONNA EGET, DO,* ROBERT F. LAVERY, MA, MICP,† LEON GARNER, DO,* STEVEN BERNSTEIN, MD,* AND KIRTI TANDON, MPH‡ The objective of this study was too determine if patients can accurately read a visual analog scale (VAS) for pain. A 100-mm visual analog pain scale designed for patient use was printed on the top page of carbonless copy paper with a perfectly aligned hatched scale on the second (bot- tom) page. Patients over the age of 18 in acute pain were enrolled in this prospective, descriptive study. Patients were asked demographic ques- tions and to indicate their pain severity with a single mark through the 100-mm scale. Once scored, patients were asked to read the number from the hatched bottom scale. Two physician-raters, blinded to pa- tients’ and each other’s readings, then scored the VAS. Analysis of physician interrater reliability and correlation of patient and physician readings was performed. One hundred forty-five patients were enrolled. Seventy-nine patients (54.5%) read the VAS exactly as physician-read- ers. One hundred thirty-eight (95.2%) read their VAS within 2 mm of physician readings. Ninety-five percent of patients are able to read a VAS within 2 mm of physician readings. The data suggests this instrument could be used by discharged patients in longitudinal pain studies or with help in management of chronic pain. (Am J Emerg Med 2003;21:515-519. © 2003 Elsevier Inc. All rights reserved.) New Joint Commission on Accreditation of Healthcare Organizations (JCAHO) pain standards state, “health care organizations should plan, support and coordinate activities and resources to assure that pain of all patients is recognized and addressed appropriately and that initial assessment and regular re-assessment of pain take place.” 1 Although EPs frequently treat pain, they rarely study the effects of anal- gesia prescribed in the ED after discharge. 2,3 This could, in part, be the result of the lack and validation of an instrument patients can use to measure pain. Although the 100-mm visual analog scale (VAS) is ar- guably the best scale to measure pain, patients have never been studied to determine if they can accurately read the 100-mm VAS themselves. Furthermore, we are not cur- rently aware of a VAS designed specifically for patient use. Limitations to implementing such an instrument would in- clude that patients have a ruler (or have one provided on discharge) and the possibility of the patient producing error while aligning the ruler and VAS. This study was designed to investigate the following 2 questions: can a 100-mm VAS, not requiring further imple- ments (such as a ruler), be designed, and can patients, regardless of pain and education level, accurately read the scale? Implications for patients’ ability to accurately read such a tool might include improved pain study designs and use of the instrument to manage discharged patients with acute or chronic pain. A self-contained VAS might also be a practical tool for use in the hospital or office setting, facilitating regular reassessment of pain and therefore in- creasing JCAHO compliance. METHODS Study Design This was a prospective observational study of the ability of patients in pain to accurately read a 100-mm VAS de- signed for home use. The institution’s investigational re- view board approved the study. Verbal informed consent was obtained from all study participants. Study Setting and Population A convenience sample of adult patients (18 y) were treated between November 1, 2000, and April 30, 2001. Specific inclusion and exclusion criteria are detailed in Table 1. The setting was the adult side of an inner-city hospital ED with an EM resident program and a combined adult and pediatric annual volume of 75,000 patients. Study Protocol In the first part of the study, a 100-mm VAS, which could be used and read by patients, was designed (Fig 1). Included in design requirement was that use of a ruler or other external instrument to read the scale would not be needed. This was accomplished by incorporating a 2-page carbon- less copy system in the design. A 100-mm unhatched VAS bounded on the left with “least possible pain” and on the right with “worst possible pain” was printed on the top page. The bottom page contained a hatched 100-mm scale, marked numerically in increments of 10 mm. Each 5-mm From the *Department of Emergency Medicine, Newark Beth Israel Medical Center (NBI), Newark, New Jersey; the †Department of Surgery, Division of Trauma, UMDNJ-New Jersey Medical School, Newark, New Jersey; and ‡St. George’s University School of Medicine, Grenada, West Indies. Manuscript received September 22, 2002, accepted September 28, 2002. Address reprint requests to David Salo, MD, PhD, Department of Emergency Medicine, Newark Beth Israel Medical Center, 201 Lyons Ave, Newark, NJ 07112. E-mail: DS1122@aol.com Key Words: VAS, patient use, pain. © 2003 Elsevier Inc. All rights reserved. 0735-6757/03/2107-0001$30.00/0 doi:10.1016/j.ajem.2003.08.022 515