The transfer of clinical prediction models for early trauma care had uncertain effects on mistriage

Abstract

Objectives: This study aimed to assess how transfers of clinical prediction models for early trauma care between different care contexts within a single health system affected mistriage rates.

Study design and setting: Patients aged 15 years or older, registered between 2011 and 2016 in the Swedish national trauma registry, SweTrau, were included. Three data set groups were created: high- and low-volume centers, metropolitan and nonmetropolitan centers, and multicenters and single centers. Clinical prediction models were developed using logistic regression in each data set group and transferred between data sets within groups. Model performance was evaluated using mistriage rate, undertriage rate, and overtriage rate. Multiple imputation using chained equations was used to handle missing data. Model performance was reported as medians with 95% confidence intervals (CIs).

Results: A total of 26,965 patients were included. Changes in mistriage rates after transfer ranged from -0.25 (95% CI -0.21 to 0.04) to 0.29 (95% CI 0.13-0.39). Both overtriage and undertriage rates were affected.

Conclusions: Transferring clinical prediction models for early trauma care is associated with substantial uncertainty in regards to the effect on model performance. Depending on the care context, model transfer led to either increased or decreased mistriage. Overtriage was more affected by model transfer than undertriage.

Keywords: Clinical prediction model; Mistriage; Overtriage; Transferability; Trauma; Undertriage.