EDTA/EDTA2 mappings

UKRDC Dataset

EDTA/EDTA2 mappings

Overview

This page documents key considerations and caveats related to the EDTA ↔ EDTA2 mappings.

Current Mapping

The current EDTA → EDTA2 and EDTA2 → EDTA mappings can be found here:

resources/codes/code_conv_lists at master · renalreg/resources

Caveat: Not all EDTA → EDTA2 mappings have an exact reverse match, see table below.

The table lists EDTA → EDTA2 mappings (forward) and the corresponding EDTA2 → EDTA mappings (reverse).

EDTA

EDTA description

EDTA2

EDTA2 description

EDTA

EDTA

EDTA description

EDTA2

EDTA2 description

EDTA

20

PYELO/INTERSTITIAL NEPHRITIS - CAUSE NOT SPECIFIED

1602

Primary reflux nephropathy - sporadic

24

21

PYELO/INTERSTITIAL NEPHRITIS - WITH NEUROGENIC BLADDER

1706

Congenital neurogenic bladder

99

22

PYELO/INTERSTITIAL NEPHRITIS - CONGEN. OBST. UROPATHY +/- REFLUX

1673

Congenital vesico-ureteric junction obstruction

99

29

PYELO/INTERSTITIAL NEPHRITIS DUE TO OTHER CAUSE (PLEASE SPECIFY)

3555

Chronic kidney disease (CKD) / chronic renal failure (CRF) - aetiology uncertain / unknown - no histology

0

49

CYSTIC KIDNEY DISEASE - OTHER SPECIFIED TYPE

2794

Cystic kidney disease

40

50

HEREDITARY/FAMILIAL NEPHROPATHY - TYPE UNSPECIFIED

3379

Familial nephropathy

59

63

CONGENITAL RENAL DYSPLASIA +/- URINARY TRACT MALFORMATION

1625

Congenital dysplasia / hypoplasia

60

70

RENAL VASCULAR DISEASE - TYPE UNSPECIFIED

2430

Atheroembolic renal disease - no histology

75

76

GLOMERULONEPHRITIS RELATED TO LIVER CIRRHOSIS

1159

IgA nephropathy secondary to liver cirrhosis - no histology

10

79

RENAL VASCULAR DISEASE - CLASSIFIED (PLEASE SPECIFY)

2411

Ischaemic nephropathy / microvascular disease - histologically proven

75

89

MULTI-SYSTEM  DISEASE - TYPE UNSPECIFIED

3555

Chronic kidney disease (CKD) / chronic renal failure (CRF) - aetiology uncertain / unknown - no histology

0

93

NEPHROCALCINOSIS / HYPERCALCAEMIC NEPHROPATHY

3555

Chronic kidney disease (CKD) / chronic renal failure (CRF) - aetiology uncertain / unknown - no histology

0

99

OTHER IDENTIFIED RENAL DISORDERS - PLEASE SPECIFY

3691

Renal failure

0

Considerations

  • The current mappings are pragmatic rather than perfect, designed to work for most use cases without complex adjustments.

  • Attempting a precise one-to-one mapping between EDTA and EDTA2 may not be feasible due to inconsistencies in the code sets.

Alternative Approach

An alternative strategy would be to map both EDTA and EDTA2 codes directly into broader categories used in annual reporting (5–10 categories). Advantages include:

  • Avoiding imperfect mappings between EDTA and EDTA2.

  • Simplifying future classification of unconstrained code lists (e.g., SNOMED codes submitted by centres) by mapping directly to analysis categories rather than hundreds of EDTA codes.

  • Maintaining consistency in analysis while reducing mapping complexity.

In most cases, this approach yields similar results for reporting purposes and may be more sustainable long-term.

Next Steps

Consider using broader category mapping for future data submissions to simplify integration and reporting.