Table 1.
Derivation of the 2018 point prevalent population with prurigo nodularis from the Clinical Practice Research Datalink (CPRD) Aurum database
| Patients included, n (%)a | Patients excluded, n (%)a | |
|---|---|---|
| All patients registered in CPRD | 42 108 395 | – |
| Acceptable CPRD status | 34 266 984 (81·4) | 7 841 411 (18·6) |
| Patient registered at primary care practice in England | 34 169 199 (99·7) | 97 785 (0·3) |
| Patient eligible for HES/ONS linkage | 21 264 007 (62·2) | 12 905 192 (37·8) |
| Recorded diagnosis of prurigo nodularisb | 11 656 (0·1) | 21 252 351 (99·9) |
| Diagnoses recorded prior to/on 30 June 2018 | 10 076 (86·4) | 1580 (13·6) |
| Patient currently registered on 30 June 2018 | 5852 (58·1) | 4224 (41·9) |
| Patient has subsequent, confirmatory diagnosis | 2743 (46·9) | 3109 (53·1) |
HES, Hospital Episode Statistics; ONS, Office for National Statistics. aPercentages refer to patients included/excluded from the preceding step. bDiagnosis of prurigo nodularis in either the Aurum or HES datasets.