ABSTRACT
The Logic Tree is a diagrammatic representation of the multiple cause-effect chains from systemic root causes to the unintended event. It uses deductive logic to expose the cause-effect chain of physical consequences (Physical Roots) resulting from decisional errors (Human Roots) that were based on underlying systems (Latent Roots). A thorough Logic Tree displays the pathway to failure from the Latent Roots up to the Event: the whole story of the unintended event. This chapter delves deeply into techniques and tips for creating an accurate RCA Logic Tree. Also explained is the difference between latent roots and contributing factors.
Asking, “How could this have occurred?” rather than “Why did this occur?” leads to hypothesis generation of multiple Physical, Human, and Latent Roots. Asking “How could?” also eliminates the implication of blame that asking “Why?” creates. This chapter describes two approaches to hypothesizing, provides countermeasures to risks in hypotheses generation, and gives advice on facilitating hypotheses generation.
>Evidence is used to verify the hypotheses. The rigor and credibility of the RCA is strengthened by showing all hypotheses and whether were ruled in or out based on evidence. Since healthcare delivery, patient factors, and pathophysiology involved in unintended events are complex, the strength and confidence of the evidence is acknowledged and addressed.
