Elder Pain: Assessment of Intensity

R29 NINR Funded
Principal Investigator: Keela Herr , PhD, RN

Purpose
The burgeoning population of elders in the United States has and will continue to increase the numbers of elders to whom nurses provide care in a variety of health care settings. Approximately 66-83% of the elder population report some degree of pain which may interfere with life activites and quality of life. There is a significant need to focus attention on accurate assessment and individualized intervention strategies tailored to alleviate or decrease pain in the elder population. Although scientific investigation has been conducted on pain assessment and intervention in non-elders, efforts to provide a similar sound scientific base for elders have been limited. The purpose of this funded project is to establish the psychometric properties and utility of selected pain intensity scales for use with elders.

Specific Aims & Results
The funded research has three phases. The specific design and aims of each phase are as follows. Phase 1 and 2 are completed and summaries are provided of findings. Phase 3 is nearing completion.

Phase 1 : administered the Faces Pain Scale (FPS) to elder subjects to determine initial psychometric properties of the FPS as a measure of pain intensity for use with elders.

Phase 1 Results : The results of Phase 1 of this research have been published in the following:
Herr, K., Mobily, P., Kohout, F., & Wagenaar, D. (1998). Evaluation of the Faces Pain Scale for Use with the Elderly, The Clinical Journal of Pain, 14, 29-38.

Phase 2 : used selected instruments, including the FPS, the numeric rating scale (NRS), the vertical visual analog scale (VAS), the verbal numeric scale (VNS) and the verbal descriptor scale (VDS), to measure the responses of elder and nonelder subjects to a laboratory-based, experimentally-induced painful to determine:

A final sample of 86 non-elderly (aged 25-55) and 89 elderly volunteer subjects (aged 65-95) completed the study.

The results of Phase 2 of the study can be summarized in the following conclusions:

• Age did not have a significant effect on use of pain intensity tools or in response to experimentally induced pain.
• Strong significant intercorrelations of the five selected pain intensity tools suggest that any of the five tools could be used to evaluate pain intensity.
• Each tool was effective in differentiating varying levels of thermal pain sensation for both age groups.
• The VNS demonstrated higher levels of pain report than the other four scales.
• The VDS discriminated best between rising intensities of thermal pain sensation..
• This study provides documentation that cognitive function, education and motor impairment do contribute to failure to use the VAS successfully.
• Although the VAS had higher failure rates, it is not ruled out as a potential tool for the elderly in selected circumstances.
• Failure rates on the other selected scales were minimal.
• Considerable increase in failures which occur on the VAS and NRS with repeated administration of the tools in a short time.
• Subjects with prior use of any instrument were able to successfully use the tools in this study. The older subjects were noted to have less prior experience with any of the tools and this seemed to impact ability to successfully complete selected scales.
• The tool most preferred to represent pain intensity by both age groups is the NRS, followed by the VDS.

Phase 3 : using the selected pain intensity measurement tools in clinical settings, using elderly and nonelderly subjects experiencing chronic pain to determine:

• and compare psychometric properties and utility of selected pain measures for pain intensity with arthritic patients who are experiencing pain;
• factors related to failure to complete a scale successfully.
• if there is a difference in tool preference for the selected pain intensity measures used, and the relationship of preference to selected variables.
• if each tool can detect differences in pain before and after joint injection with lidocaine.

  Phase 3 Results : In process