Validation of data capture in the Australasian shunt registry with a prospectively maintained institutional database

The Australasian Shunt Registry was established in 2016 with the aim of providing safety and quality data in addition to enhancing capacity for research to improve health outcomes for patients with cerebrospinal fluid shunts. The Queensland Children's Hospital is the largest single contributor of paediatric patient data to the Registry and maintains an independent institutional shunt database. The aim of this study was to validate the demographic data and outcomes captured by the Registry against that institutional database.

Data from the institutional database and a sample of data from the same institution held by the Australasian Shunt Registry were acquired from the period of 1 January 2017 to 1 October 2024. Patients ≤ 18 years of age undergoing placement of a new ventriculoperitoneal shunt system were included. Revision and mortality data were acquired from the Australasian Shunt Registry and Queensland statewide electronic medical records independently. Comparison was made between demographic and mortality data captured by each database. The primary outcome of time to shunt revision (shunt survival) in each sample was assessed through the generation of Kaplan-Meier curves and analysis by both Wilcoxon and log-rank tests.

Over the study period the shunt registry reported a full or partial opt-out rate of 9.5 %. 344 patients were identified and included from the institutional database, and 294 patients were included from the Registry. The identified patient samples were demographically similar with a mean age of 5 years, and 44 % female in both groups. The most common aetiologies of hydrocephalus in both cohorts were congenital (28 % vs 28 %, p = 0.49), tumour (33 % vs 27 %, p = 0.08) and haemorrhage (25 % vs 18 %, p = 0.02). Mortality during followup was consistent across both samples (13 % vs 11 %, p = 0.27). Similarly, binary revision status during the followup period was similar (34 % vs 32 %, p = 0.3). Kaplan-Meier analysis of time to revision (shunt survival) estimated shunt survival to be 4.82 years (95 % CI 4.42--5.22 years) in the institutional database and 5.25 (95 % CI 4.81-5.69 years) in the Registry with no significant differences between the samples on Wilcoxon, p = 0.3 or late Log-Rank, p = 0.36 tests.

The Australasian Shunt Registry appears to capture a valid sample which is representative of the demographics and clinical outcomes of patients treated at one large contributing institution. Ongoing efforts to ensure comprehensive data capture at all participating sites are justified to ensure that future findings derived from Registry data are representative of the studied population.