| Level I | Good quality evidence |
Systematic review of RCTs with consistent findings High quality individual RCT |
| Level II |
Limited quality patient orientated evidence |
Systematic review of lower quality studies or studies with inconsistent findings Low quality clinical trial Cohort studies Case-control studies |
| Level III | Other |
Consensus guidelines, extrapolations from bench research, usual practice, opinion, disease-oriented evidence (intermediate or physiologic outcomes only), or case series |
[13] Morphine infusion: Flogegård H, Ljungman G. Characteristics and adequacy of intravenous morphine infusions in children in a paediatric oncology setti ng. Med Pediatr Oncol. 2003;40:233-238. AND Poe-Kochert C, Tripi PA, Potzman J, Son-Hing JP, Thompson GH. Continuous intravenous morphine infusion for postoperative analgesia following posterior spinal fusion for idiopathic scoliosis. Spine. 2010;35:754-757. AND Lynn AM, Opheim KE, Tyler DC. Morphine infusion after pediatric cardiac surgery. Critical Care Medicine. 1984;12:863-866. AND Van Dijk M, Bouwmeester NJ, Duivenvoorden HJ et al. Efficacy of continuous versus intermittent morphine administration after major surgery in 0–3-year-old infants; a double-blind randomized controlled trial. Pain. 2002;98:305-313. AND Burrows FA, Taylor RH, Hillier SC. Early extubation of the trachea after repair of secundum-type atrial septal defects in children. Canadian Journal of Anaesthesia. 1992;39:1041-1044.