Assessing data quality from the Clinical Practice Research Datalink: a methodological approach applied to the full blood count blood test

Journal of Big Data

Table 3 Number of mismatched pairs per FBC parameter

FBC parameter (medical code)	FBC parameter (entity code)	Number of mismatched pairs
Strata 1^a:
White blood cell count (38,198)	Lymphocyte count (208)	43,869
Neutrophil count (18)	Haemoglobin (173)	425
Mean corpuscular haemoglobin concentration (30)	Mean corpuscular haemoglobin (180)	48
Mean corpuscular volume (10)	White blood cell count (207)	4
Haemoglobin (795)	Mean corpuscular volume (182)	3
Strata 2^b:
Mean platelet volume (14,166)	Platelets (189)	2,267,404
Basophil proportion (14,096)	Basophil count (313)	1,647,073
Eosinophil proportion (19,760)	Eosinophil count (168)	1,579,993
Lymphocyte proportion (17,621)	Lymphocyte count (208)	1,590,215
Monocyte proportion (13,775)	Monocyte count (183)	1,601,135
Neutrophil proportion (17,622)	Neutrophil count (184)	1,586,187
Strata 3^c:
One indicates FBC but the other indicates anything other than FBC		638,650

^aWhere one code suggested a particular FBC parameter but the other suggested a different FBC parameter, with existing medical or entity codes for both parameters that could have been assigned
^bWhere the medical code suggested one of the six FBC parameters without an existing entity code
^cWhere one code suggested a particular FBC parameter but the other suggested the record was not FBC-related