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Root cause analysis (RCA)

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RCA is a method used that is used to address a problem, orserious adverse events., in order to get to the root cause ofthe problem.RCA is now widely deployed as an error analysis tool inhealth care.RCA is simply the application, common sense techniqueswhich can produce a systematic quantified anddocumented approach to the identification, understandingand resolution of underlying causes.RCA thus uses the systems approach to identify both activeerrors (errors occurring at the point of interface betweenhumans and a complex system) and latent errors (thehidden problems within health care systems thatcontribute to adverse events).

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Many hospitals and health-care facilities are now using a processcalled RCA.RCA was first developed in engineering and is now used in manyindustries, including health care.A RCA is used after an incident has occurred to uncover the primarycauses. As such, it focuses on the particular incident and thecircumstances surrounding it.However, there are many lessons to be gained from thisretrospective process that may prevent similar incidents in thefuture.RCA is a defined process that seeks to explore all of the possiblefactors associated with an incident by asking what happened, why ithappened and what can be done to prevent it from happeningagain.

(World Health Organization, 2012. For permission to reprint, reproduce, use extracts or translateplease apply at http://www.who.int/about/licensing/en/index.htm)

Characteristics of RCAThe defining characteristics of root cause analysisinclude:

• review by an inter-professional teamknowledgeable about the processes involved in theevent;

• analysis of systems and processes rather thanindividual performance;

• deep analysis using “what” and “why” probesuntil all aspects of the process are reviewed andcontributing factors are considered;

• identification of potential changes that could bemade in systems or processes to improve performanceand reduce the likelihood of similar adverse events orclose calls in the future.

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RCA helps people answer the question of why theproblem occurred in the first place.

It seeks to identify the origin of a problem using aspecific set of steps, with associated tools, to find theprimary cause of the problem, so that you can:Determine what happened.Determine why it happened.

Figure out what to do to reduce the likelihood that itwill happen again.

You'll usually find three basic types of causes:

Physical causes – Tangible, material items failed insome way (for example, a car's brakes stoppedworking).Human causes – People did something wrong, or didnot do something that was needed. Human causestypically lead to physical causes (for example, no onefilled the brake fluid, which led to the brakes failing).Organizational causes – A system, process, or policythat people use to make decisions or do their work isfaulty (for example, no one person was responsible forvehicle maintenance, and everyone assumed someoneelse had filled the brake fluid).

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Review retrospectively ask the following set ofquestions:

What happened?Who was involved?When did it happen?Where did it happen?How severe was the actual or potential harm?What is the likelihood of recurrence?What were the consequences?

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1.Define theproblem

2.Understandthe problem

3. ImmediateAction

4. Correctiveaction

5.Confirm thesolution

5 Basic steps to completing RCA

Define the problem:Try and use SMART principles, i.e. Specific; Measurable,Actions oriented; Realistic; Time constrained.

Understand the problem:Check the information, obtaining real data regardingthe problem, gaining a clear understanding of theissues. (can be used various tools, such as Cause andEffect, brainstorming)

Immediate action:Implement temporary counter-measures at the placeof the problem. The further away from the problemsource the solution is determined.

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Corrective action:Determine and prioritize the most probable underlyingcauses of the problem, as temporary counter-measuremay not resolve the root cause. Taking correctiveactions to at least mitigate or preferably eliminate thecauses.

Confirm the solution:After the measures have been determined andimplemented the success of the adopted approachneeds to be established. Having confirmed the successof the suggested solution the rules or control methodsneed to be established that will avoid the problem everhappening again.

RCA Tools & Techniques

1. 5 WHY’ s (Gemba Gembutsu)2. Cause & Effect diagrams3. Causal Tree (Problem tree)

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1. “ASK WHY 5 TIMES” TECHNIQUE• Getting to the Root of a Problem Quickly• Sakichi Toyoda, one of the fathers of the Japanese

industrial revolution, developed the technique in the1930s. He was an industrialist, inventor and founder ofToyota Industries. His technique became popular in the1970s and Toyota still uses it to solve problems today.

• The 5 Whys technique is most effective when theanswers come from people who have hands-onexperience of the process being examined.

• It is remarkably simple: when a problem occurs, youuncover its nature and source by asking "why" no fewerthan five times.

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Each time you ask "why," look for an answer that isgrounded in fact:This prevents the 5 Whys becoming just a process ofdeductive reasoning, which can generate a number ofpossible causes and, sometimes, create moreconfusion.Keep asking "why" until you feel confident that youhave identified the root cause and can go no further.If you're not sure whether you have uncovered the realroot cause, consider using a more in-depth problem-solving technique like Root Cause Analysis .Bear in mind that this questioning process is best suitedto simple to moderately-difficult problems. Complexproblems may benefit from a more detailed approach

Problemstatement

One sentence description of event orproblem

Why?Why?Why?Why?Why?Root Cause(s) 1.

2.3.To validate root causes, ask the following: Ifyou removed this root cause, would thisevent or problem have been prevented?

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Problem Statement: You are on your way home from work and yourcar stops in the middle of the road.1. Why did your car stop? – Because it ran out of gas.2. Why did it run out of gas? – Because I didn’t buy any gas on my wayto work.3. Why didn’t you buy any gas this morning? – Because I didn’t haveany money.4. Why didn’t you have any money? – Because I lost it all last night in apoker game.5. Why did you lose your money in last night’s poker game? – BecauseI’m not very good at “bluffing” when I don’t have a good hand.

As you can see, in both examples the final Why leads the team to astatement (root cause) that the team can take action upon.It is much quicker to come up with a system that keeps the salesdirector updated on recent sales or teach a person to “bluff” a handthan it is to try to directly solve the stated problems above withoutfurther investigation.

2.“Cause and Effect Diagrams”

A Problem whichhas occurred

A Potential futureproblem

Cause:Events/conditionsthat led to theproblem

Effect:Symptoms thatwould result fromthe problem

Cause:Events/conditionsthat would lead tothe problem

Effect:Symptoms thatprovide evidenceof the problem

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“Cause-Effect Relationship”A Problem whichhas occurred

Cause:Events/conditionsthat led to theproblem

Effect:Symptoms thatprovide evidenceof the problem

Action

Corrective Adaptive

Eliminates the causeof a problem

Limits the effect of aproblem or deviation

The Fishbone diagram, alsoknown as Cause and EffectDiagram or Ishikawa

Diagram is a simplerepresentation from thefamily of causal diagrams,used to identify manydifferent causes for an effect(or issue).

A visual tool used to identify,explore and graphicallydisplay all the possiblecauses related to a problemto discover root causes.

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Cause & Effect Diagrams, Fishbone Diagrams,Ishikawa Diagrams, Herringbone Diagrams, and

Fishikawa Diagrams.• This diagram-based technique, which

combines Brainstorming with a type of Mind Map

• Cause and Effect Analysis was devised by Professor KaoruIshikawa, a pioneer of quality management, in the 1960s.

• Consists of the following major elements:– The Effect: The head of the fish. Which is the effect under analysis.

Users generally highlight the text associated to the fish heads in orderto make it relevant.

– The Spine: The spine is the connecter between causes categories.– The Branches: Each branch represents a set of causes, representing a

category. All causes in a branch should be related.– The Cause: Each root cause factor identified should be placed in the

diagram as a leaf of a branch.

There are four steps to using the tool.-Identify the problem-Work out the major factors involved-Identify possible causes-Analyze your diagram

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Step 1: Identify the Problem (Effect)

First, write down the exact problem you face. Where appropriate,identify who is involved, what the problem is, and when and whereit occurs.

Then, write the problem in a box on the left-hand side of a largesheet of paper (the head of the fish), and draw a line across thepaper horizontally from the box.

This arrangement, looking like the head and spine of a fish, givesyou space to develop ideas.

Step 2: Work Out the Major Factors InvolvedNext, identify the factors that may be part of the problem (the majorcategories of causes).

These may be systems, equipment, materials, external forces, peopleinvolved with the problem, and so on.As a starting point, you can use models such as the McKinsey 7SFramework (which offers you Strategy, Structure, Systems, Sharedvalues, Skills, Style and Staff as factors that you can consider) orthe 4Ps of Marketing (which offers Product, Place, Price, andPromotion as possible factors).

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Step 3: Identify Possible Causes through brainstorming

Now, for each of the factors you considered in step 2, brainstormpossible causes of the problem that may be related to the factor.

Identify specific causes within each major category that may beaffecting the problem.

Show these possible causes as shorter lines coming off the "bones" ofthe diagram.

Where a cause is large or complex, then it may be best to break itdown into sub-causes. Show these as lines coming off each causeline.

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3. CAUSAL TREE/ PROBLEM TREEThis is a graphical technique that provides a systematic descriptionof the combinations of possible occurrences in a system, thismethod can combine system and human failures.

The tree can either be presented left to right or top to bottom. Linkthe cards using arrows, first in draft with a pencil.

Work forward the effects of the initial problem. These will becomethe branches of the tree.

Ensure that all agree with the tree. Heated debates might takeplace. Review the tree and verify its validity and completeness.Possibly some important problems have not yet been mentioned.Finalize the tree and arrows with a marker.

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