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Social functioning Claudicants n = 48 Critical ischaemia n = 42 P-value 29.9 (27.2–48.5)
0.0 (0.0–24.2) 54.2 (28.8–84.2)
0.0 (0.0–25.1) .003
.75 36.5 (22.0–42.0)
68.7 (50.0–87.5) 31.0 (22.0–41.0)
62.5 (50.0–78.1) .27
.41 *A higher score (100) indicates more perceived problems. ** A higher score (100) indicates fewer perceived problems. a P-value, claudicants versus
critical ischaemia patients before revascularization. Tested by Mann-Whitney U-test. p-value = <0.05 showed a higher internal consistency except for social
functioning one-year postoperatively and was more
responsive in detecting changes over time in the IC group.
The NHP was more sensitive in discriminating among levels of ischaemia regarding pain and more able to detect
changes in the CLI group.
The attrition or loss of subjects (27%) in this study could
have affected the outcome. Further analysis showed that
there were no significant differences in quality of life, sex,
age, method of treatment and severity of disease between
the attrition group and those who completed the study.
The fact that the NHP and SF-36 differ in their nature and
content may limit the study design. Therefore the analyses
in this study focused only on the comparable domains of
the two instruments, including the basic domains of physical, mental and social health identified by the WHOQOL
group . A suitable quality of life instrument for patients
with chronic lower limb ischaemia should not only be
valid, reliable and responsive but also simple for elderly
people to understand and complete. In this study there
was no difference in response rate between the two instruments and both seemed to be user-friendly and took
about 5–10 minutes to complete. The findings strengthen
earlier results suggesting that both scales are practical and
acceptable to use in elderly patients [37,38].
A generic quality of life instrument, designed for a variety
of populations and measuring a comprehensive set of
health concepts, is likely to have problems with "ceiling"
and "floor" effects . In this study the NHP showed
higher "ceiling" effects in all dimensions than the SF-36.
There were minor "floor" effects in both the NHP and SF36, indicating the lowest possible quality of life. This is in
accordance to Klevsgård et al,  who also showed higher "ceiling" effects in social isolation, emotional reactions
and energy for the NHP than the SF-36. Other studies
have also reported fewer "ceiling" and "floor" effects in
the SF-36 than in the NHP in patients with chronic
obstructive pulmonary disease  and after a myocardial
infarction . The advantage of the SF-36 may be due to
its use of a Likert-type response format with a number of
possible different scores and its ability to detect positive as
well negative states of health, whereas the NHP items are
dichotomous and state more extreme ends of ill health
. This could mean that a patient with ac...
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- Fall '13
- World Health Organization, NHP, lower limb ischaemia