HTS: IVR MERET

A recent article in the Journal of the American Medical Association¹ compared two measurement methods for assessing change in pain and disability: (1) serial assessments made at two points in time and (2) retrospective assessments of change made at one time point. The former method is commonly used in clinical trials, whereas the later is most often used by clinicians. The study found that retrospective measures were more sensitive to change than serial measurements and correlated better with patients' satisfaction with treatment.

Healthcare Technology Systems, Inc. (HTS) has offered Patient Global Impression of Improvement (PGI) ratings to customers conducting clinical trials for several years. The standard PGI is implemented via interactive voice response (IVR) by first asking patients if the condition for which they are being treated has improved, worsened, or remained unchanged. If a change is indicated, the extent of the change (very much, much, or a little) is then reported. The result of this process produces a score on a 7-point scale from "very much better" (1) to "very much worse" (7), with the midpoint (4) indicating no change.

Feedback from customers using the PGI has generally been positive. A methodological weakness in the method, however, is that it requires study subjects to accurately recollect their experiences at the outset of a trial for later comparison. Memory is largely a reconstructive process, and the accuracy of reconstruction is profoundly affected by the passage of time. Thus, comparisons of current emotional or physical states to experiences two weeks earlier are easier, and probably more accurate and sensitive, than comparisons to subjective experiences twelve weeks earlier. It is well known that recognition memory, based on some type of prompt, is more accurate than direct access to recall memory. HTS believes that unique features of IVR can be used to enhance the sensitivity and usefulness of retrospective patient reports, such as the PGI.

Specifically, HTS proposes to ask patients enrolled in clinical studies to describe in their own voice and words the feelings and experiences related to their condition at baseline. These descriptions are recorded to digitized voice files and then be played back to the patients prior to asking for subsequent retrospective reports concerning change. Subjects have the ability to listen to their own words as many times as they like before rating their current experiences relative to that anchor. We expect that through access to their own statements - the selection of particular words and phrases, hesitations, mumbled speech, and expressions of affect through vocal inflections - patients would be better able to recognize and reconstruct the specific memory traces reflecting their experiences at the time of the recording. Much like the phenomenon whereby each individual is best able to read his own handwriting, each individual is uniquely able to understand and interpret his own words and vocal intonations.

By providing this experiential anchor, we believe that the accuracy and sensitivity of retrospective judgments relative to the prior emotional state would be substantially enhanced. HTS would welcome the opportunity to collaborate with you to explore these exciting possibilities.

1. Fischer, D. Stewart, AL. Bloch, DA. et al. Capturing the patient's view of change as a clinical outcome measure. JAMA 282:1157-1162. 1999.