The Ontario Prehospital Advanced Life Support (OPALS) Study Part II: Rationale and methodology for trauma and respiratory distress patients

The Ontario Prehospital Advanced Life Support (OPALS) Study represents the largest prehospital study yet conducted, worldwide. This study will involve more than 25,000 cardiac arrest, trauma, and critically ill patients over an 8-year period (1994-2002). The current article, Part II, describes in de tail the rationale and methodology for major trauma and respiratory distres s patients and for an economic evaluation of Advanced Life Support (ALS) pr ograms in the OPALS Study. The OPALS Study, using a rigorous controlled met hodology and a large sample size, should clearly indicate the benefit in tr auma and respiratory distress patient survival and morbidity that results f rom the widespread introduction of prehospital ALS programs to communities of many different sizes.