K₃EDTA Vacuum Tubes Validation for Routine Hematological Testing

Table 1

Variability in hematological parameters from two different brands of K₃EDTA vacuum tubes.

		Comprehensive results
Hematological parameters (unit)	Desirable Bias (%)	Tube I	Tube II	Mean % difference
				(𝑃 value)
RBC^* (×10^6/𝜇L)	1.7	5.12 ± 0.41 [4.28–5.71]	5.08 ± 0.40 [4.31–5.64]	0.8 (<0.01)
HCT^* (%)	1.7	43.5 ± 3.1 [37.9–49.4]	42.9 ± 3.1 [36.9–49.1]	1.4 (< 0.01)
HGB^* (g/dL)	1.8	14.31 ± 1.13 [12.80–16.70]	14.29 ± 1.15 [12.70–16.70]	0.1 (0.56)
MCV^** (fL)	1.2	85.9 ± 6.7 [81.4–87.6]	85.6 ± 6.7 [81.1–87.0]	0.4 (< 0.01)
MCHC^** (pg)	1.4	28.6 ± 3.1 [26.6–29.3]	28.9 ± 3.2 [26.6–29.3]	−1.0 (0.87)
RDW^** (%)	1.7	12.6 ± 1.1 [12.4–13.6]	12.6 ± 1.1 [12.4–13.7]	0.0 (0.94)
WBC^* (×10^3/𝜇L)	5.6	5.80 ± 1.08 [4.00–7.91]	5.88 ± 1.11 [3.94–8.01]	−1.4 (0.15)
LYMPHO^* (×10^3/𝜇L)	7.4	1.90 ± 0.66 [0.81–3.33]	1.92 ± 0.70 [0.78–3.64]	−1.0 (0.54)
MONO^* (×10^3/𝜇L)	13.2	0.35 ± 0.13 [0.17–0.69]	0.36 ± 0.12 [0.21–0.63]	−2.9 (0.27)
NEU^* (×10^3/𝜇L)	9.0	3.35 ± 0.73 [2.38–4.93]	3.37 ± 0.72 [2.48–5.09]	−0.6 (0.36)
EOS^* (×10^3/𝜇L)	19.8	0.15 ± 0.10 [0.02–0.36]	0.15 ± 0.10 [0.02–0.37]	0.0 (0.75)
BASO^* (×10^3/𝜇L)	15.4	0.041 ± 0.016 [0.020–0.070]	0.044 ± 0.020 [0.010–0.090]	−7.3 (0.38)
LUC^* (×10^3/𝜇L)	NA	0.154 ± 0.048 [0.070–0.260]	0.158 ± 0.054 [0.070–0.270]	−2.6 (0.41)
PLT^* (×10^3/𝜇L)	5.9	298.3 ± 61.5 [228.0–431.0]	292.7 ± 56.3 [224.0–407.0]	1.9 (0.02)
MPV^* (fL)	2.3	8.45 ± 0.69 [7.30–9.80]	8.75 ± 0.84 [7.40–10.6]	−3.6 (< 0.01)
PDW^** (%)	1.4	54.4 ± 6.6 [48.9–57.2]	51.8 ± 10.4 [48.8–58.6]	4.8 (< 0.01)

^*Normal distribution; the values were mean ± standard deviation (range: minimum-maximum); 𝑃 value represents the significance by paired Student’s 𝑡-test.
^**Nonnormal distribution; the values were median ± standard deviation (5th–95th percentiles); 𝑃 value represents the significance by Wilcoxon ranked-pairs test.
The bold 𝑃 values are statistically significant (𝑃<0.05), and bold mean % differences represent clinically significant variations, when compared with desirable bias [15].
NA: not available [15].
Tube I: 4.5 mL Labor Import lot 20100505 (concentration of K₃EDTA inside the tube is not made known by Shandong Weigao Group Medical Polymer, Weihai, China).
Tube II: 1.2 mL S-Monovette lot 0092201 with 1.6 mg K₃EDTA (Sarstedt, Nümbrecht, Germany).