Table 2.

Summary of baseline data collection for the randomised controlled trial

Demographics/social	Age, sex, ethnicity, marital status, education level, smoking history
Clinical	Primary renal disease, date first seen by a nephrologist, renal replacement therapy history, co-morbidities, prescribed medication (including erythropoiesis-stimulating agents and phosphate binders), 24-h urine volume (within the 6 weeks preceding randomisation)
Resource use	Day case and inpatient hospital admissions (including surgical procedures), nursing home/residential home days/hospice days, other hospital out-patient services, and primary care and community services in the last 6 months
Laboratory	Creatinine, urea, Kt/V, urea reduction ratio, albumin, haemoglobin, haematocrit, mean corpuscular volume, sodium, potassium, bicarbonate, corrected calcium, phosphate, C-reactive protein, intact parathyroid hormone, total cholesterol (from the date of the study visit or the closest date prior to the study visit)
Physical assessment	Height, weight, blood pressure, heart rate
Patient reported	EQ-5D-5L, Dialysis Symptom Index and time to recovery [31]

Follow-up will continue for a minimum of 32 months and a maximum of 91 months. It will be undertaken through a combination of 6-monthly patient questionnaires and by linkage to routine healthcare databases — Hospital Episode Statistics, Civil Registration, Public Health England (PHE) to September 2021 and UK Health Security Agency (UKHSA) from October 2021, and the UKRR in England, and the equivalent databases in Scotland and Wales, as necessary (Table 3). Only data that are collected as part of routine care will be collected. Paper and electronic (web portal) options will be offered to patients for patient questionnaire completion.