Background, Developing a Measurement Model and Items

Chapter 1

Development of the Brief Pain Inventory

The Brief Pain Inventory (BPI) has become one of the most widely used measurement tools for assessing clinical pain. The BPI allows patients to rate the severity of their pain and the degree to which their pain interferes with common dimensions of feeling and function. Initially developed to assess pain related to cancer, the BPI has been shown to be an appropriate measure for pain caused by a wide range of clinical conditions. The BPI has been used in hundreds of studies. In some ways, the BPI is a “legacy” instrument— a self-report measure that has, over time, become a standard for the assessment of pain and its impact.

Background

In the late 1970s, it became increasingly evident that patients with cancer, especially the later stages of the disease, experienced incapacitating pain that was often poorly controlled. A constellation of events— the publishing of opinion pieces by prominent persons with cancer pain, the increasing advocacy of pain professionals and organizations for better cancer pain management, a growing awareness of the problem by national and international policy groups, and the simple recognition that pain often could be controlled— created the climate for a sustained effort to improve pain management for those with cancer.

A first step in this effort was to document the extent of poor pain management. The National Cancer Institute (NCI) and the Cancer Unit of the World Health Organization (WHO) wanted measurement instruments that would better capture the severity and impact of cancer pain and measure improvement in pain after changes in analgesic practice or implementation of new pain treatments. These instruments also needed to function well in large-scale national and international studies of the epidemiology of cancer pain.

With grant support from both the NCI and the WHO, the Pain Research Group at the University of Wisconsin Medical School- Madison, under the direction of Charles S. Cleeland, PhD, undertook a program to test and develop self-report measures of cancer pain and to apply them to studies of pain and its treatment in the United States and internationally. The Pain Research Group, now the Department of Symptom Research at The University of Texas M. D. Anderson Cancer Center, was also the WHO Collaborating Center for Symptom Research in Cancer.

Developing a Measurement Model and Items

Several existing pain measures (such as the McGill Pain Questionnaire; Melzack, 1975) were field-tested in interviews with cancer patients who had pain (N=50). Almost all of these measures had been designed to assess pain in patients with nonmalignant disease. The patients reported that the measures were too complex and too long, making them excessively burdensome for patients with high levels of pain. Patients also noted that the existing instruments included items not relevant to cancer patients and sometimes required responses that patients felt were ambiguous (Cleeland, 1984). Patients were also asked what questions they felt were the most important for communicating their experience of pain. The results of this study made clear that a new measurement instrument was needed.

The Pain Research Group planned a program to develop such an instrument. The aims were to have a scale that: (a) would take only a short time to complete; (b) would be easy for patients to understand; (c) could be self-administered for literate patients, or be completed by interview for illiterate or low-literacy patients; (d)