PCRS Properties

Normative Data

Formal normative studies of the PCRS have not been conducted, and few studies using the PCRS have employed a control group. However, Prigatano et al. (1998) reported that a group of 28 Spanish control subjects achieved a mean of 144 (range 120-150) on the PCRS while respondents rating them produced a mean of 145 (range 134-150). This suggests that control subjects and their respondents agreed closely, and that the majority of items were rated at the maximum competency (5, "can do with ease") for these uninjured controls.

A larger study using a control group of 131 New Zealanders (Leathem et al., 1998) did not report the total PCRS scores. Instead, these authors grouped some of the PCRS items into 4 categories (ADL, emotional behavior, interpersonal behavior, and cognition) and reported mean control scores across items in each group. Means were between 4 ("fairly easy to do") and 5 ("can do with ease") with the exception of items relating to emotional control (mean = 3.81). Interestingly, informants rated control subjects higher on these items than the subjects rated themselves.

Reliability

Test-retest reliability of the PCRS has been reported as r = .97 for patients and r = .92 for relatives (Prigatano, Altman & O'Brien, 1990). One-week test-retest reliability for a group of uninjured college students was .82 (Heilbronner et al., 1993). Fleming et al. (1998) reported acceptable one-week test-retest reliability for patients with TBI using intraclass correlations (ICC r = .85). In the same study, internal consistency was strong for both patient ratings (Cronbach's alpha = .91, n = 55) and relatives' ratings of patients (Cronbach's alpha = .93, n = 50).

Validity

The interpretation of the PCRS rests on the assumption that the rating of the significant other (relative or clinician) is a true measure of competency against which to assess the accuracy of the patient's self-rating. The developers of the scale acknowledge that this assumption remains to be validated (see Prigatano, 1996).

PCRS discrepancy scores correlate significantly with indices of injury severity in some studies (Prigatano et al., 1998) but not others (Prigatano & Altman, 1990). Attempts to correlate the PCRS with specific neuropsychological findings have generally produced negative or equivocal results (Prigatano & Altman, 1990; Ranseen et al., 1990). In several studies PCRS discrepancy scores have correlated negatively with measures of depression or emotional distress (Ranseen et al., 1990; Fleming et al., 1998), lending support to the idea that emotional reactions to disability follow the onset of deficit awareness.