What is already known about this topic and why is it important?

The UKRR collects data on comorbidity at the time of starting renal replacement therapy. This suggests wide variation between children’s kidney units. However, there is a lot of missing data. It is thought that increasingly complex cases are being accepted for dialysis and transplantation. This information is very important for both clinicians and health service commissioners. It will enable the planning of services in the future. It will enable us to understand whether things change in the future.

How will you carry out your study?

We asked every UK children’s kidney unit to improve the data held by the registry about disabilities and comorbidities when starting treatment. The data collection has ended with all 13 centres taking part and has taken 18 months. We now want to see if the comorbidity differences are explained by case mix. For example, do differences in race, socio-economic status and kidney disease explain these findings? We will use a statistical technique called regression to assess this.

How will you decide which patients are included in your study?

We will analyse data on existing (prevalent) patients from 2015. This is because the children’s kidney units collected data on this cohort.

How many patients do you anticipate including?

Approximately 950

For how long will you follow up these patients?

We will look at factors when these patients started treatment only. However, the data quality has now been improved allowing future comparisons to be made.

What new information will your study generate and how will this benefit patients?

This study will tell us whether patient factors explain the differences in comorbidity between children’s kidney units. If differences are not explained by patient factors then it suggests that medical practice might differ between units. This information will be valuable in designing and planning children’s dialysis and transplant services.