Table 1. Characteristics of the 238 patients.
| Source | Variable | Statistic | Result |
|---|---|---|---|
| Original | Age (years)* | Median (IQR) | 71.0 (59.8–79.3) |
| eGFR (ml/min)* | Median (IQR) | 16 (11–27) | |
| Female/Male | Ratio | 147/91 = 1.62/1 | |
| CKD stage 3 | N (%) | 43 (18.1) | |
| CKD stage 4 | N (%) | 96 (40.3) | |
| CKD stage 5 | N (%) | 99 (41.6) | |
| Hemoglobin (g/dl) | Mean ± SD | 9.6 ± 1.4 | |
| Hb < 10 g/dl | N (%) | 135 (56.7%) | |
| Hb < 11 g/dl (%) | N (%) | 192 (80.7%) | |
| Ferritin level (ng/ml)* | Median (IQR) | 180.5 (82.3–353.0) | |
| Ferritin < 100 ng/ml | N (%) | 68 (28.6%) | |
| Ferritin < 500 ng/ml (%) | N (%) | 203 (85.3%) | |
| TSAT *,** | Median (IQR) | 19.0% (14.0%– 28.0%) | |
| TSAT < 20% ** | N (%) | 81 (52.9%) | |
| TSAT < 30%** | N (%) | 121 (79.1%) | |
| Ferritin < 100 ng/ml and/or TSAT < 20%+ | N (%) | 122 (68.5%) | |
| Ferritin ≤500 ng/ml and TSAT ≤30% ++ | N (%) | 114 (68.3%) | |
| Agreement** | Kappa (95%CI)£ | .47 (.32 - .62) | |
| Imputed | TSAT *,*** | Median (IQR) | 20.1% (13.6%– 28.8%) |
| TSAT < 20% *** | N(%) | 118(49.6%) | |
| TSAT < 30%*** | N(%) | 181(76.2%) | |
| Ferritin < 100 ng/ml and/or TSAT < 20%*** | N(%) | 146(61.5%) | |
| Ferritin ≤500 ng/ml and TSAT ≤30% *** | N(%) | 167(70.2%) | |
| Agreement*** | Kappa (95%CI)$ | .47 (.32 - .62) |
*: Distribution departed significantly from a normal distribution, thus the median and its Interquartile Range (IQR = Q1- Q3) were used.
**: Original data, 153 observations with non-missing values.
***: Average of 5 datasets with n = 238 each. Imputed values were derived by multiple imputation algorithms.
+: Due to the logical construction of the test, the denominator is 178.
++: Due to the logical construction of the test, the denominator is 167.
£: 95% Confidence interval by bootstrapping, based on 1000 bootstrap samples.
$: 95% Confidence interval using kappa ± 1.96 SE (no bootstrapping with multiple imputation).