T he overall aim of the NHS R&D Health Technology Assessment (HTA) programme is to ensure that high-quality research information on the costs, effectiveness and broader impact of health technologies is produced in the most efficient way for those who use, manage and work in the NHS. Research is undertaken in those areas where the evidence will lead to the greatest benefits to patients, either through improved patient outcomes or the most efficient use of NHS resources.The Standing Group on Health Technology advises on national priorities for health technology assessment. Six advisory panels assist the Standing Group in identifying and prioritising projects. These priorities are then considered by the HTA Commissioning Board supported by the National Coordinating Centre for HTA (NCCHTA).This report is one of a series covering acute care, diagnostics and imaging, methodology, pharmaceuticals, population screening, and primary and community care. It was identified as a priority by the Primary and Community Care Panel and funded as project number 95/37/01.The views expressed in this publication are those of the authors and not necessarily those of the Standing Group, the Commissioning Board, the Panel members or the Department of Health. The editors wish to emphasise that funding and publication of this research by the NHS should not be taken as implicit support for the recommendations for policy contained herein. In particular, policy options in the area of screening will be considered by the National Screening Committee. This Committee, chaired by the Chief Medical Officer, will take into account the views expressed here, further available evidence and other relevant considerations.Reviews in Health Technology Assessment are termed 'systematic' when the account of the search, appraisal and synthesis methods (to minimise biases and random errors) would, in theory, permit the replication of the review by others.

Evidence supporting the validity, reliability and utility of paediatric alert criteria is weak. Studies are needed to determine which physiological parameters or combinations of parameters, best predict serious adverse events. Prospective evaluation of validity, reliability and utility is then needed before widespread adoption into clinical practice can be recommended.

Context: Early and accurate recognition of the deteriorating hospitalised child is complex. Paediatric track and trigger systems (PTTS) support clinical decisionmaking by 'tracking' the child's condition through monitoring of clinical signs and 'triggering' a request for an appropriate review when pre-determined criteria are breeched.Objective: To describe the number and nature of published PTTS and appraise the evidence on their validity, calibration, and effect on important patient outcomes (death, cardiac and/or respiratory arrest, unplanned transfer to intensive/high dependency care, immediate/urgent request for review, rapid response system activation).Method: GRADE methodology. Papers identified through Electronic database and citation searching. ResultsThirty-three PTTS were identified from 55 studies. There was considerable variety in the number and type of parameters, although all contained one or more vital signs.The evidence to support PTTS implementation was very low and the majority of outcomes did not achieve statistical significance. When PTTS was implemented as part of a rapid response system, the evidence was moderate to low but there was some evidence of a statistically significant improvement in outcome. 3 ConclusionThere is now some limited evidence for the validity and clinical utility of PTTS scores. The high (and increasing) number of systems is a significant confounder.Further research is needed particularly around the thresholds for the vital signs and the reliability, accuracy and calibration of PTTS in different settings. Background