Based on: DiCenso, A, Bayley, L, Haynes, B. (2009). "Accessing preappraised evidence: fine-tuning the 5S model into a 6S model." ACP J Club 151:3, pp.1-1.
Retrieved from: Clinical Information Access Portal (CIAP). (N.D.) "EBP Learning Module: Introduction to Evidence-Based Practice and CIAP: Levels of Evidence."