Article

OBJECTIVE: To evaluate the reliability, standard error of the mean (SEM),
clinical significant change, and known group validity of 2 assessments of
endurance strength to low loads in patients with fibromyalgia syndrome (FS).
DESIGN: Cross-sectional reliability and comparative study. SETTING: University
Pablo de Olavide, Seville, Spain. PARTICIPANTS: Middle-aged women with FS (n=95)
and healthy women (n=64) matched for age, weight, and body mass index (BMI) were
recruited for the study. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES:
The endurance strength to low loads tests of the upper and lower extremities and
anthropometric measures (BMI) were used for the evaluations. The differences
between the readings (tests 1 and 2) and the SDs of the differences, intraclass
correlation coefficient (ICC) model (2,1), 95% confidence interval for the ICC,
coefficient of repeatability, intrapatient SD, SEM, Wilcoxon signed-rank test,
and Bland-Altman plots were used to examine reliability.
A Mann-Whitney U test
was used to analyze the differences in test values between the patient group and
the control group. We hypothesized that patients with FS would have an endurance
strength to low loads performance in lower and upper extremities at least twice
as low as that of the healthy controls. RESULTS: Satisfactory test-retest
reliability and SEMs were found for the lower extremity, dominant arm, and
nondominant arm tests (ICC=.973-.979; P<.001; SEMs=1.44-1.66 repetitions). The
differences in the mean between the test and retest were lower than the SEM for
all performed tests, varying from -.10 to .29 repetitions. No significant
differences were found between the test and retest (P>.05 for all). The
Bland-Altman plots showed 95% limits of agreement for the lower extremity (4.7 to
-4.5), dominant arm (3.8 to -4.4), and nondominant arm (3.9 to -4.1) tests. The
endurance strength to low loads test scores for the patients with FS were 4-fold
lower than for the controls in all performed tests (P<.001 for all). CONCLUSIONS:
The endurance strength to low loads tests showed good reliability and known group
validity and can be recommended for evaluating endurance strength to low loads in
patients with FS. For individual evaluation, however, an improved score of at
least 4 and 5 repetitions for the upper and lower extremities, respectively, was
required for the differences to be considered as substantial clinical change.
Patients with FS showed impaired endurance strength to low loads performance when
compared with the general population.
CI - Copyright (c) 2012 American Congress of Rehabilitation Medicine. Published by
Elsevier Inc. All rights reserved.

Langue : ANGLAIS