Method comparison between Alinity hq and Sysmex XT-4000i in an emergency laboratory

Area of Science:

• Clinical Laboratory Science
• Hematology
• Medical Technology

Background:

• Modern haematology analysers are increasingly complex.
• Laboratories must validate new instruments against existing ones before adoption.
• Method agreement studies are crucial for ensuring diagnostic consistency.

Purpose of the Study:

• To quantify the method agreement between Sysmex XT-4000i and Alinity hq analysers.
• To determine if these two haematology analysers can be used interchangeably in a clinical setting.
• To assess the clinical significance of observed analytical differences.

Main Methods:

• Analysis of 415 complete blood counts (CBC) from adult patients.
• Comparison of results from Sysmex XT-4000i (reference) and Alinity hq analysers.
• Statistical analysis including Spearman Correlation, Bland-Altman test, and Passing-Bablok regression.
• Comparison of analytical differences with Reference Change Value (RCV) at medical decision levels (MDL).

Main Results:

• Good agreement was observed for cell differentiation and counting between the two analysers.
• Cell counting and haemoglobin measurements showed good agreement across all medical decision limits.
• Minor analytical differences exceeded the Reference Change Value for Haematocrit (HCT) and Mean Corpuscular Haemoglobin Concentration (MCHC).

Conclusions:

• The Sysmex XT-4000i and Alinity hq analysers demonstrate good overall agreement for most CBC parameters.
• Observed differences, particularly in RBC indices like MCHC, are likely due to differing technologies but are unlikely to impact clinical decision-making.
• The findings support the potential interchangeability of these analysers for routine haematological analysis.