Measuring Quality in Emergency Medical Services: A Review of Clinical Performance Indicators

Table 1

Structure-Process-Outcome Model for EMS systems PIs.

Indicator Type	Definitions	EMS systems PI examples	Advantages	Limitations
Structure	Characteristics of the different components of the system	(i) Facilities; (ii) Equipment; (iii) Staffing; (iv) Knowledge base of providers; (v) Credentials; (vi) Deployment; (vii) Response times	(i) Standardized structural data allows for comparison between systems structure	(i) Indirect measure of quality; (ii) Difficult to relate to outcome; (iii) Problematic with EMS system design diversity
Process	Combination or sequence of steps in patient care intended to improve patient outcome	(i) Medical protocols; (ii) Medication administration; (iii) Transport to appropriate facility	(i) Direct measure of quality; (ii) Specific input for improvement; (iii) Easy to understand and to evaluate; (iv) Does not require Risk adjustment; (v) Easy data collection; (vi) Best for technical skill evaluation; (vii) Short-term evaluation	(i) Strict criteria for generalization; (ii) Can become very complex with more advanced care (i.e., complex processes)
Outcome	Changes in health and well-being related to antecedent care 6 D’s*; (i) Death; (ii) Disease; (iii) Disability; (iv) Discomfort; (v) Dissatisfaction; (vi) Destitution	(i) Out of hospital cardiac arrest survival; (ii) Patient Satisfaction; (iii) Improvement in pain score	(i) Easy to understand; (ii) Feedback about all aspects of care provided; (iii) Long-term outcomes	(i) Indirect measure of quality; (ii) Requires Risk adjustment and standardization of data collection

*EMS outcomes defined by Emergency Medical Services Outcomes Project (EMSOP).