User's Guide for the Environmental Utility Measure (EUMTM)

User's Guide for the Environmental Utility Measure (EUMTM)

ENVIRONMENTAL UTILITY MEASURE (EUMTM)

Difficulty Rating Scale (DRSTM)

Acceptability Rating Scale (ARSTM)

Gary Scott Danford, Ph.D.

Edward Steinfeld, Arch.D.

Center for Inclusive Design & Environmental Access

School of Architecture & Planning

State University of New York at Buffalo

Buffalo, NY 14214-3087

June 18, 2001 Limited Circulation Draft

ENVIRONMENTAL UTILITY MEASURE (EUMTM)

The Environmental Utility Measure (EUMTM) enables one to examine a person’s perceptions of both the relative ease or difficulty as well as the acceptability of performing certain purposeful activities in different physical environmental contexts. The EUMTM’s two scales - i.e., the Difficulty Rating Scale (DRSTM) and the Acceptability Rating Scale (ARSTM) - collectively provide an initial “indicative” measure of the goodness of fit between the person and the near physical environment. The EUMTM enjoys the principal advantage of most such survey instruments - i.e., low costs of administration. And when used to assess the perceptions of persons with impairments, the EUMTM enables measurement of individual differences that may prove to be significant correlates of subsequent functional independence and performance.

Difficulty Rating Scale (DRSTM)

The Difficulty Rating Scale (DRSTM) is an adaptation of a previously developed, tested and published sequential judgment unipolar rating scale with 15 points (i.e., 0-14) (Pitrella & Kappler, 1988). Using a similar approach, we developed a simpler 7-point bipolar rating scale (see Figure 1) and made some other improvements.

This outcome measure was designed to elicit subjective reactions to the experience of an activity in a selected physical environment. Using the DRSTM , a person rates the relative ease or difficulty of performing an activity through a two step process. Pitrella & Kappler determined that a scale with a large number of points is more sensitive than one with only a few and a sequential judgment task is a less complex task than a direct discrimination (1968).

Figure 1 – The Difficulty Rating Scale (DRSTM)

STEP ONE

The task of using the DRSTM seven point rating scale is simplified to an initial choice between only three options.

The DRSTM Initial Judgment

In the “Initial Judgment” (see Figure 2), the interviewer asks the person to indicate whether the functional performance of a just completed activity seemed "difficult," "moderate" or "easy.”

Figure 2 – The DRSTM Initial Judgment

STEP TWO

In the second step, the interviewer asks the person to position that initial judgment at a specific location on the relevant subsection of the 7-point scale. Three overlapping subscales are used.

The DRSTM Difficult Subscale

If the person’s initial judgment was that performance of the activity was “difficult,” the person is presented with the “Difficult Subscale” (see Figure 3) and asked to point to the position on that subscale that best describes “how difficult?” The person has five choices: “very difficult” (-3), “moderately difficult” (-2), “barely difficult” (-1) or either of two positions between the three anchor points (-2.5 and –1.5).

Figure 3 – The DRSTM Difficult Subscale

The DRSTM Moderate Subscale

If the person’s initial judgment was that performance of the activity was “moderate” (i.e., neither difficult nor easy), the person is presented with the “Moderate Subscale” (see Figure 4) and asked to point to the position on that subscale that best describes “how moderate?” The person has five choices: “barely difficult” (-), “neither” difficult nor easy (0), “barely easy” (+1) or either of the two positions between the three anchor points (-.5 and +.5).

Figure 4 – The DRSTM Moderate Subscale

The DRSTM Easy Subscale

If the person’s initial judgment was that performance of the activity was “easy,” the person is presented with the “Easy Subscale” (see Figure 4) and asked to point to the position on that subscale that best describes “how easy?” The person has five choices: “barely easy” (+1), “moderately easy” (+2), “very easy” (+3) or either of the two positions between the three anchor points (+1.5 and +2.5).

Figure 5 – The DRSTM Easy Subscale

Acceptability Rating Scale (ARSTM)

An ease or difficulty rating does not necessarily indicate level of acceptance. For example, individuals may rate an environment difficult to use but still acceptable given their impairments and expectations. Thus, the Acceptability Rating Scale (ARSTM) (see Figure 6) was designed as an identically formatted companion to the DRSTM to provide an indication of the acceptability of the near physical environment.

Figure 6 – The Acceptability Rating Scale (ARSTM)

STEP ONE

As with the DRSTM, the task of using the ARSTM seven point rating scale is simplified to an initial choice between only three options.

The ARSTM Initial Judgment

In the “Initial Judgment” (see Figure 7), the interviewer asks the person to indicate whether the rated acceptability of a just completed activity seemed "unacceptable," "moderate" or "acceptable.”

Figure 7 – The ARSTM Initial Judgment

STEP TWO

Paralleling the DRSTM process, the interviewer then asks the person to position that initial judgment at a specific location on the relevant subsection of the 7-point scale. Again, three overlapping subscales are used.

The ARSTM Unacceptable Subscale

If the person’s initial judgment was that usability rating of the activity was “unacceptable,” the person is presented with the “Unacceptable Subscale” (see Figure 8) and asked to point to the position on that subscale that best describes “how unacceptable?” The person has five choices: “very unacceptable” (-3), “moderately unacceptable” (-2), “barely unacceptable” (-1) or either of two positions between the three anchor points (-2.5 and –1.5).

Figure 8 – The ARSTM Unacceptable Subscale

The ARSTM Moderate Subscale

If the person’s initial judgment was that usability rating of the activity was “moderate” (i.e., neither unacceptable nor acceptable), the person is presented with the “Moderate Subscale” (see Figure 9) and asked to point to the position on that subscale that best describes “how moderate?” The person has five choices: “barely unacceptable” (-), “neither” unacceptable nor acceptable (0), “barely acceptable” (+1) or either of the two positions between the three anchor points (-.5 and +.5).

Figure 9 – The ARSTM Moderate Subscale

The ARSTM Acceptable Subscale

If the person’s initial judgment was that usability rating of the activity was “acceptable,” the person is presented with the “Acceptable Subscale” (see Figure 10) and asked to point to the position on that subscale that best describes “how acceptable?” The person has five choices: “barely acceptable” (+1), “moderately acceptable” (+2), “very acceptable” (+3) or either of the two positions between the three anchor points (+1.5 and +2.5).

Figure 10 – The ARSTM Acceptable Subscale

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