Preliminary Evaluation of Cell Population Data Parameters in Different Blood Collection Tubes on Sysmex XN-Series Analysers
1
EOLAS Research Group, Cork University Hospital, Wilton, T12 DC4A Cork, Ireland
2
Department of Haematology, Cork University Hospital, Wilton, T12 DC4A Cork, Ireland
*
Author to whom correspondence should be addressed.
LabMed 2025, 2(3), 15; https://doi.org/10.3390/labmed2030015
Submission received: 2 May 2025
/
Revised: 8 June 2025
/
Accepted: 15 August 2025
/
Published: 26 August 2025
Abstract
Cell population data (CPD) parameters generated by Sysmex XN-series analysers are promising biomarkers for a variety of disease states. Routine use of CPD parameters, however, will require extensive evaluation of potential pre-analytical variables that may affect reliability. At present, no information on the comparability of CPD parameters generated using different blood collection tubes is available. In this preliminary study, we evaluated the impact of four commonly used blood collection tubes—dipotassium (K2) EDTA, tripotassium (K3) EDTA, trisodium citrate, and lithium heparin—on the generation of CPD parameters in whole blood from a cohort of 10 healthy donors. We also evaluated the stability of the CPD parameters generated at 4 h post-collection. Statistically significant differences in the CPD were observed across all blood collection tubes: whole blood anticoagulated with K3EDTA induced minimal biases and was comparable to whole blood anticoagulated with K2EDTA at collection; however, whole blood anticoagulated with citrate and heparin were associated with more substantial and more widespread biases in several parameters with potential clinical relevance. Notably, the biases observed in whole blood anticoagulated with K3EDTA increased in both number and magnitude at 4 h post-collection, whilst the CPD parameters generated with whole blood anticoagulated with K2EDTA remained stable. Although further confirmatory investigations are required, these findings highlight the importance of anticoagulant selection, as well as the need for further pre-analytical research, to support the integration of CPD parameters generated by Sysmex XN-series analysers into routine diagnostic workflows.
Keywords:
anticoagulant; blood tubes; cell population data; citrate; heparin; K2-EDTA; K3-EDTA; Sysmex1. Introduction
Cell population data (CPD) parameters available on Sysmex XN-series analysers are emerging biomarkers that provide quantitative data regarding the morphological and functional characteristics of circulating blood cells [1]. These parameters are generated alongside traditional haematological indices by flow cytometric analysis of whole blood, following pre-incubation with proprietary surfactants and fluorescent dyes. The analysis results in a multidimensional scattergram, where each axis corresponds to specific cellular properties [1]: the X-axis represents granularity via the side-scattered light; the Y-axis represents nucleic acid content via the fluorescent light intensity; and the Z-axis represents volumetric size and shape via the forward-scattered light.
Recent studies have demonstrated that the CPD parameters available on Sysmex XN-series analysers are potential adjuncts in both the diagnosis and prognosis of a broad range of disease states, encompassing not only hematological disorders, such as myelodysplasia [2,3] and myeloid malignancies [4], but also non-hematological disorders, such as systemic inflammation [5], sepsis and septic shock [6,7,8,9], and viral infection [10,11,12,13]. However, CPD parameters are currently designated for research-use-only and are not yet routinely incorporated into clinical laboratory practice due to methodological concerns [14]. One such concern lies in the potential variability introduced by the type of blood collection tube used during venepuncture.
Ethylenediaminetetraacetic acid (EDTA), trisodium citrate, and lithium heparin are the most used anticoagulants in routine clinical laboratory practice. Among these, dipotassium (K2) and tripotassium (K3) EDTA are the most frequently employed for routine haemocytometric analysis. Although the dipotassium salt is recommended as the anticoagulant of choice [15], traditional indices generally exhibit non-significant differences when whole blood is anticoagulated with the tripotassium salt [16], with the exception of morphology-related indices such as the mean cell volume, the mean platelet volume, and red cell distribution width [17]. Indeed, studies have shown that EDTA-dependent changes in blood cell morphology can occur within 30 min of collection across multiple lineages, including—but not limited to—cytoplasmic fragmentation, degranulation, and/or the development of Pelger-Huet forms for neutrophils and vacuolisation for monocytes [18]. Given that the CPD parameters available on Sysmex XN-series analysers are both dependent and sensitive to changes in blood cell morphology, the anticoagulant in the blood collection tube may have a more substantial effect on the CPD parameters than traditional haematological indices.
However, the effect of common anticoagulants on CPD parameters is largely uncharactertised. Recent studies on Beckman Coulter DxH-series analysers, which employ optical and electrical detection as opposed to the fluorescent flow cytometric detection on Sysmex XN-series analysers, have shown that CPD parameters can be significantly influenced by the type of anticoagulant present in the blood collection tube [19,20]. Indeed, the monocyte distribution width (MDW) parameter on Beckman Coulter DxH-series analysers—which has been recently approved for the early detection of sepsis—is significantly influenced by the type of anticoagulant present [19,20]. As a result, the diagnostic cut-offs for the MDW parameter differ depending on the anticoagulant used [21]. Whether the CPD parameters available on Sysmex XN-series analysers are similarly susceptible to anticoagulant-associated changes is unknown. Therefore, we report a preliminary evaluation study of CPD parameters generated by Sysmex XN-series analysers designed to explore the presence of potential biases associated with the use of different blood collection tubes.
2. Materials and Methods
2.1. Sample Collection
A total of 10 participants (4 males and 6 females; age range: 22–30 years) were recruited to this study. This study was approved by the Clinical Research Ethics Committee of the Cork Teaching Hospitals and informed consent was obtained prior to recruitment. All participants were ostensibly healthy at the time of venepuncture and had no recent history of morphological or quantitative changes in the full blood count. Whole blood samples were collected by an experienced phlebotomist into blood tubes containing either dipotassium (K2) or tripotassium (K3) EDTA, 3.2% trisodium citrate, or lithium heparin (Grenier Bio-One VACUETTE®, Cruinn Diagnostics, Dublin, Ireland).
2.2. Haemocytometric Analysis
All samples were processed manually on a single XN-20 analyser (Sysmex, Kobe, Japan) within 30 min of collection (T1) and again at 4 h post-collection (T2). The analyser was maintained in accordance with the instructions of the manufacturer and quality controlled across the analytical range with three levels of XN-CHECK™ (Sysmex, Kobe, Japan). The CPD parameters evaluated in this study are provided in Table 1.
2.3. Statistical Analysis
Data were assessed for normality using the D’Agostino–Pearson test; accordingly, data were expressed as means with standard deviation, and statistical differences were determined using the paired Student’s t test. A p-value of <0.05 was considered statistically significant. Biases between blood collection tubes were calculated as follows: bias = ([value − reference value]/reference value × 100%). The value determined from the blood collection tube containing dipotassium (K2) EDTA was considered the reference value, as the International Council for Standardization in Hematology recommends K2EDTA as the anticoagulant of choice for haemocytometric testing [15]. Biases between the blood collection tubes were considered as potentially clinically relevant if greater than predefined maximum permissible difference (MPD) values [22]. The MPD values, which incorporate both analytical and biological variation to determine the clinical relevance of any change in result, were determined according Oddoze et al. [22]: MPD = [(0.277 × CVa)2 + (0.5 × CVi)2]½, where CVa was the in-house analytical imprecision for each CPD parameter and where CVi was the short-term within-subject biological variation for CPD parameter as reported by Buoro et al. [23]. All data were curated using Microsoft Excel (version 2018; Microsoft Corporation, Redmond, WA, USA), and all statistical analyses were performed using GraphPad Prism (version 10.1.1; GraphPad Software, Boston, MA, USA).
3. Results
3.1. Cell Population Data Parameters Generated Across Different Blood Collection Tubes
The CPD parameters generated in this study were within published ranges for all of the blood collection tubes evaluated [24]. However, statistically significant differences were identified for all possible CPD parameters within 30 min of collection when whole blood anticoagulated with K3EDTA, trisodium citrate, or lithium heparin were compared to those generated in whole blood anticoagulated with K2EDTA (Table 2, Table 3 and Table 4), which was chosen as the reference in accordance with the guidelines of the International Council for Standardization in Hematology [15]. Moreover, we observed that both the extent and magnitude of the biases were not consistent across the blood collection tubes, with many exceeding the pre-defined MPD values for potential clinical relevance [22].
For whole blood anticoagulated with K3EDTA, only two parameters—NEUT-RI and LY-X—exhibited biases that exceeded the MPD when compared to whole blood anticoagulated with K2EDTA (Table 2). Notably, the differences were relatively minor, suggesting that both blood collection tubes containing K2EDTA and K3EDTA tubes may be interchangeable for the evaluation of most CPD parameters on Sysmex XN-series analysers.
In contrast, more extensive and substantial biases were observed for whole blood anticoagulated with trisodium citrate. Several CPD parameters—including NEUT-GI, NEUT-RI, LY-X, LY-Y, LY-Z, MO-Y, MO-Z, NE-WX, NE-WZ, LY-WX, and LY-WZ—exhibited biases that substantially exceeded the MPD when compared to whole blood anticoagulated with K2EDTA (Table 3). Similarly, extensive and substantial biases were also observed for whole blood anticoagulated with lithium heparin. Several nearly overlapping parameters, including NEUT-GI, NEUT-RI, LY-X, LY-Y, LY-Z, MO-Y, MO-Z, NE-WX, NE-WZ, and LY-WZ, exhibited biases that substantially exceeded the MPD when compared to whole blood anticoagulated with K2EDTA (Table 4).
For both trisodium citrate and lithium heparin, the extent of the biases was not only more widespread but also generally greater in magnitude when compared to those generated in blood collection tubes containing K3EDTA (Table 2, Table 3 and Table 4). It is noteworthy, however, that four parameters—NE-Z, MO-X, NE-WY, LY-WY—remained consistent across all the different blood collection tubes evaluated (Table 2, Table 3 and Table 4), with biases not exceeding the predefined MPD value. As such, these preliminary findings suggest that while blood collection tubes containing K3EDTA may be a suitable alternative to those containing K2EDTA for the evaluation of CPD parameters, the use of trisodium citrate or lithium heparin as anticoagulants introduces significant variability.
3.2. Cell Population Data Parameter Stability Across Different Blood Collection Tubes
We next evaluated whether there were differences between CPD parameters within 30 min of collection (T1) and 4 h post-collection (T2), given that recent studies have suggested that pre-analytical variability in the MDW on the Beckman Coulter DxH-series analysers may exhibit temporal changes depending on the blood collection tube and the anticoagulant used [25]. As significant biases were evident for CPD parameters generated in blood collection tubes containing both trisodium citrate and lithium heparin within 30 min of collection, we limited this further evaluation to only those containing K2EDTA and K3EDTA.
On Sysmex XN-series analysers, CPD parameters are generally considered stable for up to 4 h [26], and in-house validation data further support their stability for up to 7 h in blood collection tubes containing K2EDTA. Consistent with these findings, our analysis showed that although some parameters demonstrated statistically significant changes, no biases were observed in any parameter generated from blood collection tubes containing K2EDTA at 4 h post-collection when compared to the baseline values (Table 5).
Conversely, while NEUT-RI and LY-X identified at baseline remained biased in blood collection tubes containing K3EDTA at the later time point, additional CPD parameters—including NEUT-GI, LY-Y, LY-Z, MO-Y, MO-Z, NE-WX, NE-WZ, and LY-WY— also exceeded the MPD when compared to whole blood anticoagulated with K2EDTA (Table 6). These findings suggest that certain biases in K3EDTA samples may amplify over time and that delayed processing may further impact the interpretability of CPD parameters in blood collection tubes containing K3EDTA.
4. Discussion
As CPD parameters on Sysmex XN-series analysers begin to transition from research-use-only designations towards routine clinical laboratory practice, it becomes essential to understand how both pre-analytical and analytical variables—such as the choice of anticoagulant in the blood collection tube—may influence the integrity and reliability of the parameters themselves.
In this preliminary evaluation study, we investigated the effects of four commonly used blood collection tubes—K2EDTA, K3EDTA, trisodium citrate, and lithium heparin—on the leukocyte CPD parameters of ostensibly healthy participants. Although the CPD values generated across the different blood collection tubes remained within the expected published ranges [24], we observed statistically significant differences within 30 min of collection for all CPD parameters generated on Sysmex XN-series analysers when whole blood anticoagulated with K3EDTA, trisodium citrate, or lithium heparin was compared to whole blood anticoagulated with K2EDTA (Figure 1). Notably, both the extent and magnitude of the observed biases varied depending on the anticoagulant used in the blood collection tube (Figure 1).
Whole blood anticoagulated with K3EDTA exhibited minor biases within 30 min of collection, with only two parameters (NEUT-RI and LY-X) exceeding the predefined MPD values. Previous studies have reported biases between routine haematological indices generated with whole blood anticoagulated with K2EDTA and K3EDTA [17,27], potentially due to the higher concentration and osmotic pressure of liquid K3EDTA compared to spray-dried K2EDTA [28]. The higher osmotic pressure can cause cellular shrinkage or distortion [28], which may, in part, explain the changes in the CPD parameters available on Sysmex XN-series analysers. The NEUT-RI parameter on Sysmex XN-series analysers has been recently incorporated into two scores for the early detection of infection, the Neutrophil-Monocyte (NEMO) Score [29] and the Intensive Care Infection Score (ICIS) [30], and though the bias is relatively minor, it is unknown at present whether the observed bias will have an effect on those recently proposed scores.
Interestingly, we observed that the biases in whole blood anticoagulated with K3EDTA increased both in number and in magnitude at 4 h post-collection, whereas those parameters generated in whole blood anticoagulated with K2EDTA remained stable. These findings are consistent with earlier reports describing time-dependent changes in haematological indices generated in whole blood anticoagulated with K3EDTA [28].
Although the CPD parameters available on Sysmex XN-series analysers are reported to be generally stable in whole blood anticoagulated with K2EDTA [26], no literature on the stability in the presence of alternative anticoagulants is currently available. Our preliminary observations are suggestive of temporal anticoagulant-dependent biases in CPD parameters. Given that both K2EDTA and K3EDTA are used for haemocytometric testing globally, these observations warrant further investigation.
In contrast to whole blood anticoagulated with K3EDTA, more substantial biases were identified with both trisodium citrate and lithium heparin across a wider range of CPD parameters. Overall, these findings suggest that blood collection tubes containing K3EDTA tubes, but not those containing trisodium citrate and lithium heparin, may be an acceptable alternative to K2EDTA for the generation of most CPD parameters, especially if the whole blood samples on are processed without delay. However, we acknowledge that the clinical significance of the observed biases cannot be inferred solely from to the predefined MPD values, as even modest deviations may may lead to patient misclassification or altered clinical decision-making, and further research is required to evaluate their impact on diagnostic performance.
Additionally, our findings suggest that the CPD parameters available on Sysmex XN-series analysers may require anticoagulant-specific cut-offs in routine clinical laboratory practice. This consideration aligns with existing practices for the MDW parameter on Beckman Coulter DxH-series analysers, for which anticoagulant-specific cut-offs have already been established [21].
Interestingly, one of the only parameters to not demonstrate significant bias across all of the blood collection tubes evaluated was the MO-X parameter. We have previously shown the MO-X parameter to be a sensitivity marker for SARS-CoV-2 [11,13], and it is also incorporated into NEMO Score [29]. Given that the MO-X parameter most closely approximates the MDW parameter on Beckman Coulter DxH-series analysers [31], this parameter may a highly suitable marker for the early detection of infection on Sysmex XN-series analysers.
This study has several important limitations that must be acknowledged. First, as a preliminary evaluation study, it was designed to explore the presence of potential biases rather than to establish definitive conclusions. It is limited by a monocentric design with a low number of samples. Second, the study cohort consisted exclusively of ostensibly healthy participants, which significantly limits the generalisability of the findings to broader patient populations. CPD parameters are most likely to be applied in disease states, such as infections, malignancies, and haematologic disorders, where the morphology and functional characteristics of circulating blood cells may deviate markedly from those observed under physiological conditions. As such, we cannot comment on whether the same biases or patterns identified in this study would be observed in patients with disease states, where altered cell populations and inflammatory responses may interact differently with various anticoagulants. Third, as only one manufacturer of blood collection tube was used, we cannot comment on whether different blood collection tubes from different manufacturers will yield the same results. Finally, we limited the preliminary evaluation study to 4 h post-collection. As such, we cannot comment on the temporal stability of the observed biases beyond 4 h. Further research is warranted to address these limitations and to confirm, as well as expand, the preliminary findings presented here.
In conclusion, this preliminary evaluation study demonstrates that several of the CPD parameters generated by Sysmex XN-series analysers are susceptible to biases across different blood collection tubes. These findings warrant further confirmatory investigations to support the clinical development of these emerging haemocytometric parameters.
Author Contributions
Conceptualisation, J.V.H.; methodology, J.V.H., C.H. and V.M.; formal analysis, J.V.H.; investigation, J.V.H. and C.H.; data curation, J.V.H. and C.H.; writing—original draft preparation, J.V.H.; writing—review and editing, J.V.H., C.H. and V.M. All authors have read and agreed to the published version of the manuscript.
Funding
This research received no external funding.
Institutional Review Board Statement
This study was conducted in accordance with the Declaration of Helsinki, and the study protocol was approved by the Clinical Research Ethics Committee of the Cork Teaching Hospitals (ECM 4 (rr) 05/12/2023 & ECM 5 (3) 05/12/2023 & ECM 3 (m) 05/02/2024); approved on 16 February 2024.
Informed Consent Statement
Informed consent was obtained from all subjects involved in the study.
Data Availability Statement
The original contributions presented in the study are included in the article; further inquiries can be directed to the corresponding author.
Acknowledgments
The authors would like to graciously thank the Department of Haematology at Cork University Hospital, Ireland, as well as members of the EOLAS Research Group, for continued support and thoughtful discussions.
Conflicts of Interest
J.V.H. declares travel support from Sysmex UK and Ireland. The authors declare no other conflicts of interest in relation to this study.
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Figure 1.
Summary of biases in cell population data (CPD) parameters across blood collection tubes at different timepoints. (A) Biased CPD parameters generated from whole blood anticoagulated with tripotassium (K3EDTA), trisodium citrate, and lithium heparin within 30 min of collection (T1). (B) Biased CPD parameters generated from whole blood anticoagulated with dipotassium (K2) or tripotassium (K3EDTA) at 4 h post-collection (T2). For both heatmaps, the columns represent the individual parameters, and the rows represent the individual blood collection tubes. Unbiased CPD parameters are represented in light grey; biased CPD parameters are represented in purple. The percentage biases were determined using dipotassium (K2) EDTA within 30 min of collection (T1) as the reference.
Figure 1.
Summary of biases in cell population data (CPD) parameters across blood collection tubes at different timepoints. (A) Biased CPD parameters generated from whole blood anticoagulated with tripotassium (K3EDTA), trisodium citrate, and lithium heparin within 30 min of collection (T1). (B) Biased CPD parameters generated from whole blood anticoagulated with dipotassium (K2) or tripotassium (K3EDTA) at 4 h post-collection (T2). For both heatmaps, the columns represent the individual parameters, and the rows represent the individual blood collection tubes. Unbiased CPD parameters are represented in light grey; biased CPD parameters are represented in purple. The percentage biases were determined using dipotassium (K2) EDTA within 30 min of collection (T1) as the reference.
Table 1.
Cell population data parameters on Sysmex XN-series analysers.
| Parameter | Unit | Description |
|---|---|---|
| NEUT-GI † | SI | Neutrophil granularity intensity |
| NEUT-RI ‡ | FI | Neutrophil reactivity intensity |
| NE-Z | ch | Mean neutrophil forward scattered light intensity |
| LY-X | ch | Mean lymphocyte side scattered light intensity |
| LY-Y | ch | Mean lymphocyte fluorescent light intensity |
| LY-Z | ch | Mean lymphocyte forward scattered light intensity |
| MO-X | ch | Mean monocyte side scattered light intensity |
| MO-Y | ch | Mean monocyte fluorescent light intensity |
| MO-Z | ch | Mean monocyte forward scattered light intensity |
| NE-WX | ch | Width distribution of the NEUT-GI parameter |
| NE-WY | ch | Width distribution of the NEUT-RI parameter |
| NE-WZ | ch | Width distribution of the NE-WZ parameter |
| LY-WX | ch | Width distribution of the LY-X parameter |
| LY-WY | ch | Width distribution of the LY-Y parameter |
| LY-WZ | ch | Width distribution of the LY-Z parameter |
| MO-WX | ch | Width distribution of the MO-X parameter |
| MO-WY | ch | Width distribution of the MO-Y parameter |
| MO-WZ | ch | Width distribution of the MO-Z parameter |
† NEUT-GI has also been known as NE-X and NE-SSC; ‡ NEUT-RI has also been known as NE-Y and NE-SFL. Abbreviations: ch, channel intensity unit; FI, fluorescence intensity unit; LY, lymphocyte; MO, monocyte; NE, neutrophil; SI, scatter intensity unit.
Table 2.
Differences in cell population data parameters between K2EDTA and K3EDTA.
| Parameter | K2EDTA T1 | K3EDTA T1 | Bias (%) | p Value | MPD (%) |
|---|---|---|---|---|---|
| NEUT-GI | 152.4 ± 3.4 | 151.8 ± 3.4 | −0.42 | <0.001 | 0.87 |
| NEUT-RI | 47.3 ± 2.2 | 49.9 ± 2.3 | 5.61 | <0.001 | 2.26 |
| NE-Z | 88.6 ± 2.7 | 88.4 ± 2.7 | −0.19 | <0.001 | 1.99 |
| LY-X | 76.1 ± 1.1 | 77.3 ± 1.2 | 1.62 | <0.001 | 0.59 |
| LY-Y | 70.7 ± 1.9 | 72.8 ± 2 | 2.94 | <0.001 | 3.36 |
| LY-Z | 56.3 ± 0.9 | 57.6 ± 0.9 | 2.33 | <0.001 | 2.50 |
| MO-X | 118.8 ± 0.7 | 119.9 ± 1.3 | 0.91 | <0.001 | 1.67 |
| MO-Y | 113.1 ± 6.2 | 118 ± 6.5 | 4.33 | <0.001 | 8.86 |
| MO-Z | 64.3 ± 1.5 | 64.8 ± 1.6 | 0.82 | <0.001 | 5.84 |
| NE-WX | 320 ± 21.6 | 315 ± 21.2 | −1.62 | <0.001 | 7.81 |
| NE-WY | 612 ± 34.3 | 601 ± 32.5 | −1.65 | 0.003 | 8.86 |
| NE-WZ | 631 ± 34.1 | 610 ± 23.0 | −3.12 | <0.001 | 8.60 |
| LY-WX | 547 ± 37.3 | 525 ± 35.9 | −3.97 | <0.001 | 14.72 |
| LY-WY | 859 ± 68.4 | 850 ± 71.8 | −1.01 | 0.002 | 9.50 |
| LY-WZ | 542 ± 13.9 | 527 ± 22.0 | −2.58 | 0.053 | 8.61 |
| MO-WX | 262 ± 17.3 | 277 ± 18.3 | 5.60 | <0.001 | 18.31 |
| MO-WY | 689 ± 93.3 | 638 ± 86.5 | −7.32 | <0.001 | 29.08 |
| MO-WZ | 573 ± 42.6 | 598.6 ± 53.4 | 4.46 | <0.001 | 19.11 |
Data is presented as mean ± standard deviation and as the mean percentage difference (%∆). T1: Parameters within 30 min of collection. Statistical significance was determined using the paired Student’s t test. A p value of <0.05 was considered statistically significant. Data in bold indicate bias greater than the maximum permissible difference (MPD) [22].
Table 3.
Differences in cell population data parameters between K2EDTA and citrate.
| Parameter | K2EDTA T1 | Citrate T1 | Bias (%) | p Value | MPD (%) |
|---|---|---|---|---|---|
| NEUT-GI | 152.4 ± 3.4 | 158.5 ± 4 | 3.98 | <0.001 | 0.87 |
| NEUT-RI | 47.3 ± 2.2 | 53.8 ± 3.6 | 13.86 | <0.001 | 2.26 |
| NE-Z | 88.6 ± 2.7 | 89 ± 2.6 | 0.49 | 0.002 | 1.99 |
| LY-X | 76.1 ± 1.1 | 78.3 ± 1.3 | 2.93 | <0.001 | 0.59 |
| LY-Y | 70.7 ± 1.9 | 73.9 ± 2.6 | 4.50 | <0.001 | 3.36 |
| LY-Z | 56.3 ± 0.9 | 60.7 ± 1.4 | 7.83 | <0.001 | 2.50 |
| MO-X | 118.8 ± 0.7 | 120.6 ± 1.8 | 1.50 | <0.001 | 1.67 |
| MO-Y | 113.1 ± 6.2 | 131.4 ± 11.1 | 16.18 | <0.001 | 8.86 |
| MO-Z | 64.3 ± 1.5 | 73.8 ± 4.2 | 14.83 | <0.001 | 5.84 |
| NE-WX | 320 ± 21.6 | 275 ± 29.1 | −14.17 | <0.001 | 7.81 |
| NE-WY | 612 ± 34.3 | 610 ± 34.1 | −0.29 | <0.001 | 8.86 |
| NE-WZ | 631 ± 34.1 | 713 ± 70.1 | 13.08 | 0.001 | 8.60 |
| LY-WX | 547 ± 37.3 | 577 ± 45.7 | 5.50 | 0.002 | 14.72 |
| LY-WY | 859 ± 68.4 | 906 ± 75.3 | 5.42 | <0.001 | 9.50 |
| LY-WZ | 542 ± 13.9 | 604 ± 48.0 | 11.50 | 0.001 | 8.61 |
| MO-WX | 262 ± 17.3 | 277 ± 20.9 | 5.56 | 0.004 | 18.31 |
| MO-WY | 689 ± 93.3 | 738 ± 115.8 | 7.16 | 0.002 | 29.08 |
| MO-WZ | 573 ± 42.6 | 588 ± 33.7 | 2.71 | <0.001 | 19.11 |
Data is presented as mean ± standard deviation and as the mean percentage difference (%∆). T1: Parameters within 30 min of collection. Statistical significance was determined using the paired Student’s t test. A p-value of <0.05 was considered statistically significant. Data in bold indicate bias greater than the maximum permissible difference (MPD) [22].
Table 4.
Differences in cell population data parameters between K2EDTA and heparin.
| Parameter | K2EDTA T1 | Heparin T1 | Bias (%) | p Value | MPD (%) |
|---|---|---|---|---|---|
| NEUT-GI | 152.4 ± 3.4 | 158.3 ± 2.6 | 3.84 | <0.001 | 0.87 |
| NEUT-RI | 47.3 ± 2.2 | 54 ± 3.9 | 14.29 | <0.001 | 2.26 |
| NE-Z | 88.6 ± 2.7 | 88.1 ± 2.7 | −0.53 | <0.001 | 1.99 |
| LY-X | 76.1 ± 1.1 | 74.1 ± 1.5 | −2.59 | 0.001 | 0.59 |
| LY-Y | 70.7 ± 1.9 | 67.6 ± 1.5 | −4.41 | <0.001 | 3.36 |
| LY-Z | 56.3 ± 0.9 | 60.8 ± 1.7 | 8.01 | <0.001 | 2.50 |
| MO-X | 118.8 ± 0.7 | 117.9 ± 2.3 | −0.77 | 0.003 | 1.67 |
| MO-Y | 113.1 ± 6.2 | 133 ± 10.2 | 17.60 | <0.001 | 8.86 |
| MO-Z | 64.3 ± 1.5 | 73.2 ± 3.7 | 13.89 | <0.001 | 5.84 |
| NE-WX | 320 ± 21.6 | 363 ± 34.3 | 13.30 | <0.001 | 7.81 |
| NE-WY | 612 ± 34.3 | 610 ± 33.7 | −0.29 | 0.001 | 8.86 |
| NE-WZ | 631 ± 34.1 | 700 ± 66.6 | 11.02 | 0.002 | 8.60 |
| LY-WX | 547 ± 37.3 | 578 ± 44.8 | 5.69 | 0.001 | 14.72 |
| LY-WY | 859 ± 68.4 | 904 ± 74.5 | 5.19 | <0.001 | 9.50 |
| LY-WZ | 542 ± 13.9 | 473 ± 12.0 | −12.68 | <0.001 | 8.61 |
| MO-WX | 262 ± 17.3 | 277 ± 20.9 | 5.56 | 0.004 | 18.31 |
| MO-WY | 689 ± 93.3 | 628 ± 85.1 | −8.81 | <0.001 | 29.08 |
| MO-WZ | 573 ± 42.6 | 588 ± 43.7 | 2.71 | <0.001 | 19.11 |
Data is presented as mean ± standard deviation and as the mean percentage difference (%∆). T1: Parameters within 30 min of collection. Statistical significance was determined using the paired Student’s t test. A p value of <0.05 was considered statistically significant. Data in bold indicate bias (%∆) greater than the maximum permissible difference (MPD) [22].
Table 5.
Differences in cell population data parameters in K2EDTA at different timepoints.
| Parameter | K2EDTA T1 | K2EDTA T2 | %∆ | p Value | MPD |
|---|---|---|---|---|---|
| NEUT-GI | 152.4 ± 3.4 | 153.1 ± 2.9 | 0.43 | 0.679 | 0.87 |
| NEUT-RI | 47.3 ± 2.2 | 47.7 ± 1.7 | 0.95 | 0.556 | 2.26 |
| NE-Z | 88.6 ± 2.7 | 86.0 ± 3.2 | −1.77 | 0.065 | 1.99 |
| LY-X | 76.1 ± 1.1 | 76.4 ± 1.3 | 0.43 | 0.478 | 0.59 |
| LY-Y | 70.7 ± 1.9 | 69.0 ± 1.4 | −2.43 | 0.376 | 3.36 |
| LY-Z | 56.3 ± 0.9 | 56.4 ± 0.9 | 0.20 | 0.758 | 2.50 |
| MO-X | 118.8 ± 0.7 | 118.8 ± 0.9 | −0.86 | 0.041 | 1.67 |
| MO-Y | 113.1 ± 6.2 | 110.5 ± 3.6 | −2.30 | 0.189 | 8.86 |
| MO-Z | 64.3 ± 1.5 | 62.7 ± 1.2 | −2.44 | 0.043 | 5.84 |
| NE-WX | 320 ± 21.6 | 313 ± 13.2 | −2.31 | 0.288 | 7.81 |
| NE-WY | 612 ± 34.3 | 585 ± 28.1 | −4.38 | 0.086 | 8.86 |
| NE-WZ | 631 ± 34.1 | 610 ± 31.8 | −3.25 | 0.217 | 8.60 |
| LY-WX | 547 ± 37.3 | 532 ± 47.3 | −2.72 | 0.436 | 14.72 |
| LY-WY | 859 ± 68.4 | 851 ± 77.1 | −0.98 | 0.777 | 9.50 |
| LY-WZ | 542 ± 13.9 | 525 ± 24.8 | −3.08 | 0.119 | 8.61 |
| MO-WX | 262 ± 17.3 | 258 ± 21.7 | −1.68 | 0.688 | 18.31 |
| MO-WY | 689 ± 93.3 | 680 ± 108.4 | −1.26 | 0.855 | 29.08 |
| MO-WZ | 573 ± 42.6 | 605 ± 49.4 | 5.68 | 0.083 | 19.11 |
Data is presented as mean ± standard deviation and as the mean percentage difference (%∆). T1: Parameters within 30 min of collection. T2: Parameters 4 h post-collection. Statistical significance was determined using the paired Student’s t test. A p value of <0.05 was considered statistically significant. The maximum permissible difference (MPD) was also determined [22].
Table 6.
Differences in cell population data parameters between K2EDTA and K3EDTA at 4 h.
| Parameter | K2EDTA T2 | K3EDTA T2 | %∆ | p Value | MPD |
|---|---|---|---|---|---|
| NEUT-GI | 153.1 ± 2.9 | 150.2 ± 4.5 | −1.89 | <0.001 | 0.87 |
| NEUT-RI | 47.7 ± 1.7 | 51.5 ± 1.8 | 7.97 | <0.001 | 2.26 |
| NE-Z | 86 ± 3.2 | 86.4 ± 3.3 | −0.69 | <0.001 | 1.99 |
| LY-X | 76.4 ± 1.3 | 77.5 ± 1.6 | 1.44 | <0.001 | 0.14 |
| LY-Y | 69 ± 1.4 | 70.7 ± 1.9 | 2.46 | <0.001 | 3.36 |
| LY-Z | 56.4 ± 0.9 | 58.8 ± 0.9 | 4.26 | <0.001 | 2.50 |
| MO-X | 117.8 ± 1.1 | 118.6 ± 0.9 | 0.68 | <0.001 | 1.67 |
| MO-Y | 110.5 ± 3.6 | 122.3 ± 3.6 | 10.68 | <0.001 | 8.86 |
| MO-Z | 62.7 ± 1.2 | 68.8 ± 2.4 | 9.73 | <0.001 | 5.84 |
| NE-WX | 313 ± 13.2 | 345 ± 18.2 | 10.22 | <0.001 | 7.81 |
| NE-WY | 585 ± 28.1 | 593 ± 35.9 | 1.37 | 0.015 | 8.86 |
| NE-WZ | 610 ± 31.8 | 681 ± 49.6 | 11.64 | <0.001 | 8.60 |
| LY-WX | 532 ± 47.3 | 551 ± 48.2 | 3.57 | 0.010 | 14.72 |
| LY-WY | 851 ± 77.1 | 904 ± 82.2 | 6.23 | <0.001 | 9.50 |
| LY-WZ | 525 ± 24.8 | 472 ± 21.5 | −10.10 | <0.001 | 8.61 |
| MO-WX | 258 ± 21.7 | 243 ± 22.2 | −5.81 | 0.195 | 18.31 |
| MO-WY | 680 ± 108.4 | 757 ± 103.6 | 11.32 | <0.001 | 29.08 |
| MO-WZ | 605 ± 49.4 | 626 ± 46.5 | 3.47 | <0.001 | 19.11 |
Data is presented as mean ± standard deviation and as the mean percentage difference (%∆). T2: Parameters 4 h post-collection. Statistical significance was determined using the paired Student’s t test. A p value of <0.05 was considered statistically significant. Data in bold indicate mean percentage differences (%∆) greater than the maximum permissible difference (MPD) [22].
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Harte, J.V.; Hoy, C.; Mykytiv, V. Preliminary Evaluation of Cell Population Data Parameters in Different Blood Collection Tubes on Sysmex XN-Series Analysers. LabMed 2025, 2, 15. https://doi.org/10.3390/labmed2030015
AMA Style
Harte JV, Hoy C, Mykytiv V. Preliminary Evaluation of Cell Population Data Parameters in Different Blood Collection Tubes on Sysmex XN-Series Analysers. LabMed. 2025; 2(3):15. https://doi.org/10.3390/labmed2030015
Chicago/Turabian StyleHarte, James V., Ciara Hoy, and Vitaliy Mykytiv. 2025. "Preliminary Evaluation of Cell Population Data Parameters in Different Blood Collection Tubes on Sysmex XN-Series Analysers" LabMed 2, no. 3: 15. https://doi.org/10.3390/labmed2030015
APA StyleHarte, J. V., Hoy, C., & Mykytiv, V. (2025). Preliminary Evaluation of Cell Population Data Parameters in Different Blood Collection Tubes on Sysmex XN-Series Analysers. LabMed, 2(3), 15. https://doi.org/10.3390/labmed2030015
