SOFTWARE QUALITY ASSURANCEROOT CAUSE ANALYSIS

Seminar: Oana FEIDIQuality Manager – Continental Automotive

WHAT IS ROOT CAUSE ANALYSIS?

a class of problem solving methods aimed at identifying the root causes of problems or events

http://www.thinkreliability.com/Root-Cause-Analysis-CM-Basics.aspx

ROOT CAUSE METHODS : ISHIKAWA are causal diagrams that show the causes of a specific

event an analyzing instrument which helps to identify, order

and print possible causes of a specific problem or a quality characteristic

graphical representation of the relation between a result and all the factors that have impact

http://www.isixsigma.com/tools-templates/cause-effect/cause-and-effect-aka-fishbone-diagram/

ROOT CAUSE METHODS : ISHIKAWAEXAMPLE

http://www.chcr.brown.edu/pain/tools.htm

ROOT CAUSE METHODS : ISHIKAWA

http://www.isixsigma.com/tools-templates/cause-effect/cause-and-effect-aka-fishbone-diagram/

ROOT CAUSE METHODS : ISHIKAWA

People Anyone involved with the process

Methods How the process is performed and the specific requirements for doing it, such as policies, procedures, rules, regulations and laws

Machines Any equipment, computers, tools etc. required to accomplish the job

Materials Raw materials, parts, pens, paper, etc. used to produce the final product

Measurements

Data generated from the process that are used to evaluate its quality

Environment The conditions, such as location, time, temperature, and culture in which the process operates

EXERCISE

Identify possible causes for the following topics:

Group 1: Burned barbecue on 1st of May event Group 2: Blurry pictures on the 1st of May event

ROOT CAUSE METHODS : 5 WHY

The 5 Whys is a question-asking technique used to explore the cause-and-effect relationships underlying a particular problem

http://www.bulsuk.com/2009/07/5-why-analysis-using-table.html#axzz1u70e6jBm

ROOT CAUSE METHODS : 5 WHY

The vehicle will not start. (the problem)

Why? - The battery is dead. (first why) Why? - The alternator is not functioning. (second why) Why? - The alternator belt has broken. (third why) Why? - The alternator belt was well beyond its useful service life and

not replaced. (fourth why) Why? - The vehicle was not maintained according to the recommended

service schedule. (fifth why, a root cause)

Why? - Replacement parts are not available because of the extreme age of the vehicle. (sixth why, optional footnote)

Start maintaining the vehicle according to the recommended service schedule. (possible 5th Why solution)

Purchase a different vehicle that is maintainable. (possible 6th Why solution)

http://en.wikipedia.org/wiki/5_Whys

ROOT CAUSE METHODS : 5 WHYCLASSIC EXAMPLE

Benjamin Franklin's 5-Why Analysis:

For want of a nail a shoe was lost, for want of a shoe a horse was lost, for want of a horse a rider was lost, for want of a rider an army was lost, for want of an army a battle was lost, for want of a battle the war was lost, for want of the war the kingdom was lost, and all for the want of a little horseshoe nail.

EXERCISE

Using the results from the previous exercise, now apply 5 Why method to identify the root cause

THANK YOU!