2010 review - Patient-Reported Outcomes Measurement - University ...

larger than for the SF-36 SF and MH subscales, although PF scales of the two measures were
comparable (Schroter & Lamping, 2006, UK). In the PTCA sample, the SRM for CROQ
Symptoms was significantly larger than for the SAQ Anginal Frequency scale, but the SRM
for CROQ PF was significantly lower than for SAQ Exertional Capacity (Schroter &
Lamping, 2006, UK). The ES for CROQ PF was significantly larger than for SF-36 PF and,
as in the CABG group, ES and SRM for the CROQ Psychosocial scale were significantly
larger than for SF-36 SF and MH (Schroter & Lamping, 2006, UK).
Responsiveness of the CROQ was further illustrated in a trial comparing the clinical
effectiveness of MIDCAB versus PTCA (Reeves et al., 2004, UK; HTA report). CROQ
scores favoured MIDCAB; however, between-group differences were statistically significant
only in the cognitive functioning domain, at three months (Reeves et al., 2004, UK). As the
authors of this study have noted, given the number of comparisons carried out (five and six
dimensions/scores at three different time points), a single significant finding should be
interpreted with caution (Reeves et al., 2004, UK).
Acceptability of the CROQ was supported by response rates of over 80% in the original
development study (Schroter & Lamping, 2000, UK), and a return rate of 87% for a battery
including the CROQ in the BHACAS trial (Ascione et al., 2004, UK); both studies used
postal administration. In the BHACAS trial (Ascione et al., 2004, UK), completion rates for
CROQ items were slightly higher than for the SF-36 and SAQ, suggesting that patients in this
sample found the measure easier to answer and/or more relevant to their circumstances
(Ascione et al., 2004, UK). There was a response rate of 72% and 62% for the CABG and
PTCA groups, respectively, in the postal survey comparing CROQ, SAQ, and SF-36
(Schroter & Lamping, 2006, UK); of those who responded, 89% and 94%, respectively,
completed the questionnaires post-revascularisation (Schroter & Lamping, 2006, UK).
Time required for completion of the measure is estimated by the developers to be 10 minutes.
c. Duke Activity Status Index, DASI (Hlatky et al., 1989)
The DASI was developed to provide a means of assessing functional capacity in cardiac
patients that would be more accurate and feasible to apply than existing measures, namely,
the NYHA and CCS classification systems (Criteria Committee of the NYHA, 1994;
Campeau, 1976), and the Specific Activity Scale (Goldman et al., 1981). It comprises 12
items representing major aspects of physical function, each weighted according to the known
metabolic cost of the activity (MET units); a difference of 2.2 units or greater has been shown
to be clinically significant (Hlatky et al., 1997). Although its content is not strictly
cardiovascular-specific, and it has been used with other clinical populations (see, for
example, Carter et al., 2002), the DASI is generally regarded as a condition-specific measure,
and is widely used with cardiovascular populations. An eight-item version has been
developed to reduce patient burden, and with a modified scoring system (Phillips et al., 1990;
Alonso et al., 1997).
Sixteen studies supporting the use of DASI with patients undergoing CABG or PCI were
identified; all were with North American samples. Fourteen studies examined outcomes of
CABG; seven studies examined PCI (six studies examined both). Three studies are very
recent.
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