For development of the risk models, data were extracted for all individuals meeting the scope of NCAA with a date of 2222 call between 1 April 2011

and 30 September 2012. Data for individual hospitals were included if the hospital had commenced participation in CB-839 nmr NCAA prior to April 2012 and had validated data for at least six months. Individual team visit records meeting the following criteria were considered ineligible for inclusion in the risk model: arrests that occurred pre-hospital (but were subsequently attended by a hospital-based resuscitation team and therefore met the scope of NCAA); second and subsequent visits to the same patient during the same hospital stay; and patients for whom it was identified, after starting resuscitation, that a ‘do not attempt cardiopulmonary resuscitation’ (DNACPR) decision was documented in the patient’s notes. The following exclusion criteria were applied to individual team visit records: patients whose last known status was still in hospital; patients missing the outcomes of return of spontaneous circulation (ROSC) for greater than 20 min or survival to hospital discharge; patients with missing data for candidate predictors. For validation of the risk models, data were extracted for all individuals in hospitals included in the development dataset with

a date of 2222 call between 1 October 2012 and 31 March 2013 and for all individuals in hospitals that commenced participation

in NCAA between April and September learn more 2012 (and were therefore not included in the development dataset) with a date of 2222 call between 1 April 2012 and 31 March 2013. The same eligibility criteria and exclusion criteria were applied at the individual team visit level as for the development dataset. Risk models were developed for two outcomes: ROSC greater than 20 min and survival to hospital discharge. Patients were followed up to discharge from the original hospital and any patients transferred to another acute hospital were reported as hospital survivors. A list of candidate predictors was established from the dataset developed and collected for NCAA. A valid predictor was considered to be any variable collected prior to or at the time of the arrival of Gemcitabine in vitro the hospital-based resuscitation team and not related to variations in the quality of care. If factors related to the quality of care were included within the risk model then the expected number of events would be adjusted to account for these factors. Consequently, a poorly performing provider would not be identified as an outlier and these discrepancies in the quality of care would not be recognised. The full list of candidate predictors is presented in Table 1. Location of arrest was not considered to be a predictor for patients with a reason for admission to/attendance at/visit to hospital of ‘staff’ or ‘visitor’.