Title: The PAINTED study: PAndemic INfluenza Triage in the Emergency Department
Funder: Department of Health and Social Care

Abstract: Objectives: To determine the discriminant value of emergency department triage methods for predicting severe illness in patients presenting with suspected pandemic influenza, to determine the discriminant value of presenting clinical characteristics and routine tests for severe illness, to determine the independent predictive value of presenting clinical characteristics and routine tests for severe illness, and to develop two new triage methods based upon (a) presenting clinical characteristics alone and (b) presenting clinical characteristics, electrocardiogram (ECG), chest X-ray and routine blood test results. Design: Prospective observational cohort study. Setting: 40 acute hospital emergency departments. Population: Patients presenting to the emergency department with suspected pandemic influenza. Interventions: Triage methods to predict need for inpatient care and critical care, including existing triage methods (CURB-65, the physiological-social score, the swine flu hospital pathway, the SMART-COP score and the SwiFT score) and potentially two new methods based on (a) presenting clinical characteristics alone (age, gender, pregnancy, obesity, co-morbidities, physiological variables) and (b) presenting characteristics, routine blood tests and chest X-ray. Outcomes: Adverse outcome, defined as death or requiring cardiovascular, respiratory or renal support. Plan of analysis: We will estimate the discriminant value of existing triage methods, clinical predictors and diagnostic tests for predicting adverse events up to 30 days. If data allow we will also use multivariate analysis to develop new triage methods. Sample size: This will ultimately depend upon the size and severity of the pandemic. We have planned for a sample size of 20,000 cases including 200 (1%) with adverse outcome. A sample of 150 with adverse outcome will allow us to estimate a c-statistic of a triage method, clinical variable or test with a standard error of 0.03 (assuming the true c-statistic was 0.8).

Lay abstract: Patients attending a hospital emergency department with suspected flu need to be rapidly assessed to identify who has severe illness and needs hospital admission, and who can be safely discharged home. This process is known as "triage" and often uses triage methods, such as scores or decision rules, that have been developed to assess the severity of illness and predict which patients are at risk of life-threatening complications. We plan to use patient data from the early phases of a flu pandemic to (1) Test how well existing triage methods predict serious complications, (2) Test how well patient characteristics (such as age, gender, existing illnesses, pregnancy or obesity), simple measurements (such as blood pressure, pulse rate or breathing rate) or diagnostic tests (such as blood tests or x-rays) predict serious complications, and (3) Develop new triage methods that predict serious complications better than existing methods. This will involve recording medical details in a standardised way from patients with suspected flu and then using hospital records to follow patients up to find out if they die or suffer a life-threatening complication. The results of our study can be used in subsequent phases of a pandemic to produce a guideline or rule to decide which patients require hospital admission. The findings can also be used by doctors and nurses to identify which individual patients are at risk of serious complications. We may also be able to identify which patient characteristics are associated with an increased risk of serious complications in a particular pandemic.

Research activity codes: 4.2 EVALUATION OF MARKERS AND TECHNOLOGIES
Health categories: INFECTION