Development and validation of a follow-up methodology for a randomised controlled trial, utilising routine clinical data as an alternative to traditional designs: a pilot study to assess the feasibility of use for the BladderPath trial

Table 5 The strongest predictors of bladder cancer survival and whether these variables can be theoretically identified from administrative or registry data, in the absence of clinical trial data

Variable	Administrative	Registry
Gender^a	✓	✓
Age^a	✓	✓
Neutrophil-lymphocyte-ratio	✗	✗
Lymphovascular invasion	✗	?
Tumour stage and grade	✗	✓
Lymph node involvement	?	✓
Neoadjuvant chemotherapy^a	✓	✓
Charlson score^a	✓	✗
Surgical margins	✗	✓

^aUsed in survival analyses. Administrative classified as HID (HES), RTDS, SACT; registry classified as cancer registration (not including individualised cancer registries) ✓ = theoretically collected, ✗ = not collected, ? = not explicitly collected (e.g. histology coded and free text field available, but lymphovascular invasion not collected individually, secondary lymph node involvement can be coded in diagnosis fields using ICD coding, but not obligatory)

ISSN: 2055-5784