title: The efficacy of advanced life support: a review of the literature.
abstract: BACKGROUND
  Jurisdictions throughout the United States and some other parts of the world have invested substantial time and resources into creating and sustaining a prehospital advanced life support (ALS) system without knowing whether the efficacy of ALS-level care had been validated scientifically. In recent years, it has become fashionable for speakers before large audiences to declare that there is no scientific evidence for the clinical effectiveness of ALS-level care in the out-of-hospital setting. This study was undertaken to evaluate the evidence that pertains to the efficacy of ALS-level care in the current scientific literature.
  
  
  METHODS
  An extensive review of the available literature was accomplished using computerized and manual means to identify all applicable articles from 1966 to October, 1995. Selected articles were read, abstracted, analyzed, and compiled. Each article also was categorized as presenting evidence supporting or refuting the clinical efficacy of ALS-level care, and a list was constructed that pointed to where the preponderance of the evidence lies.
  
  
  RESULTS
  Research in this field differs widely in terms of methodological sophistication. Of the 51 articles reviewed, eight concluded that ALS-level care is not any more effective than is basic life support, seven concluded that it is effective in some applications but not for others, and the remainder demonstrated effectiveness. The strongest support for ALS-level care was in the area of responses to victims of cardiac arrest, whereas somewhat more divergent findings related to trauma or non condition-specific studies.
  
  
  CONCLUSIONS
  While not unanimous, the predominant finding of recent research into the clinical effectiveness of advanced life support demonstrates improved effectiveness over basic life support for patients with certain pathologies. More outcomes-based research is needed.
authors: Department of Emergency Health Services, University of Maryland-Baltimore Campus, USA.
authors: R A
authors: RA
authors: Bissell
authors: D G
authors: DG
authors: Eslinger
authors: L
authors: L
authors: Zimmerman
mesh_terms: D004632:Emergency Medical Services / Q000379:methods / Q000592:standards*; D006323:Heart Arrest / Q000401:mortality / Q000628:therapy; D006801:Humans; D008020:Life Support Care / Q000379:methods / Q000592:standards*; D011787:Quality of Health Care; D012640:Seizures / Q000401:mortality / Q000628:therapy; D015996:Survival Rate; D014481:United States; D014947:Wounds and Injuries / Q000401:mortality / Q000628:therapy