AMIA ... Annual Symposium proceedings / AMIA Symposium. AMIA Symposium
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AMIA Annu Symp Proc · Jan 2009
Inductive creation of an annotation schema and a reference standard for de-identification of VA electronic clinical notes.
Accessing both structured and unstructured clinical data is a high priority for research efforts. However, HIPAA requires that data meet or exceed a deidentification standard to assure that protected health information (PHI) is removed. This is a particularly difficult problem in the case of unstructured clinical free text and natural language processing (NLP) systems can be trained to automatically de-identify clinical text. ⋯ Annotation schema must be created that can be used to build reliable and valid reference standards to evaluate NLP systems for the deidentification task. We describe the inductive creation of an annotation schema and subsequent reference standard. We also provide estimates of the accuracy of human annotators for this particular task.
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AMIA Annu Symp Proc · Jan 2009
Using Bayesian networks and rule-based trending to predict patient status in the intensive care unit.
Multivariate Bayesian models trained with machine learning, in conjunction with rule-based time-series statistical techniques, are explored for the purpose of improving patient monitoring. Three vital sign data streams and known outcomes for 36 intensive care unit (ICU) patients were captured retrospectively and used to train a set of Bayesian net models and to construct time-series models. Models were validated on a reserved dataset from 16 additional patients. ⋯ The model's AUC for predicting declining outcome increased from 70% to 85% when the model was indexed to personalized baselines for each patient. The rule-based trending and alerting system was accurate 100% of the time in alerting a subsequent decline in condition. These techniques promise to improve the monitoring of ICU patients with high-sensitivity alerts, fewer false alarms, and earlier intervention.