Supplementary Material
Title: Risks and predictors of mild diastolic dysfunction among middle-aged and aged
women: a population based cohort study
Authors: Jing Wu; Siyun Yu; Lijuan Zhang; Da Wo; Miaomiao Zhao; Jue Li
Intra and Inter-observer variability Analysis
We randomly sampled 20 subjects (aged 46–72 years; average age 54.4±8.15 years) for the
reproducibility study. Each patient was examined by twice by two separate observers over an
interval of one week to record echocardiography measurements. Using this data, we
determined the inter-observer and intra-observer variability analysis. The intra- and
inter-observer variability was expressed as the percent error for each echocardiography
variable and was determined as the difference between the two observations divided by their
mean value. The Pearson correlation coefficients for paired measurements were also
calculated.
Variables
E/e’ ratio
Intra-observer
Variability (%)
3.52±3.65
5.09±6.25
Inter-observer
Variability (%)
3.13±4.63
5.77±6.33
Correlation coefficient
for Intra-observer
0.947
0.926
Correlation coefficient
for Inter-observer
0.913
0.908
E/A ratio
6.14±5.76
6.30±7.15
0.974
0.922
LAD (mm)
5.78±6.80
7.36±6.95
0.853
0.802
LVIDd (mm)
5.91±4.39
3.88±5.15
0.884
0.942
PVWT (mm)
8.47±9.37
8.38±9.02
0.816
0.823
IVST (mm)
7.34±10.58
9.14±11.78
0.847
0.789
LVEF (%)
According to the method of Bland–Altman, the differences between the repeated
measurements, d1=(X1-X2), are plotted against their mean value, d2=(X1+X2)/2. Because the
repeated measurements used the same method, the mean difference should be zero. Therefore,
the coefficient of repeatability can be calculated as 1.96 times the standard deviations of the
differences between the two measurements (called ‘limits of agreement’). The limits of
agreement between measurements for Intra-observer reproducibility (Fig.1 A–G) and Interobserver reproducibility (Fig.2 A–G) showed no significant systematic bias, thus
demonstrating good reproducibility.

The Bland–Altman plots assessment for Intra-observer Variability
Figure 1 (A–G) The Bland–Altman plots graphs displayed a scatter diagram of the differences
plotted against the averages of the two measurements for the Intra-observer Variability.
Horizontal lines are drawn at the mean difference, and at the limits of agreement, which are
defined as the mean difference plus and minus 1.96 times the standard deviation of the
differences.

The Bland–Altman plots assessment for the Inter-observer Variability
Figure 2 (A–G) The Bland–Altman plots graphs displayed a scatter diagram of the differences
plotted against the averages of the two measurements for the Inter-observer Variability.
Horizontal lines are drawn at the mean difference, and at the limits of agreement, which are
defined as the mean difference plus and minus 1.96 times the standard deviation of the
differences.