Six Sigma Foundations and Principles

six sigma

a methodology to minimize variation, eliminate defects, and improve quality and efficiency

continuous improvement

reduces costs, increases customer satisfaction, and improves bottom lines

common cause variation

natural fluctuations like subtle differences in 2 cups of coffee

special cause variation

unexpected and traceable to specific events; significant unpredictable changes

Root cause analysis

identifies underlying causes of variation; asks “why?” many times

Control charts

distinguish between common and special cause variation and measure key parameters

Process mapping

visualizes process steps and decision points to identify areas of process variation and redundant steps

DMAIC

a structured approach for problem solving and improvement; Define, Measure, Analyze, Improve, and Control

Define Phase

articulate problem and establish project goals focused on cost reduction or quality improvement

Measure Phase

collect quantitative data to establish baseline performance and determine what/how to measure

Analyze Phase

identify root causes using statistical tools to distinguish between symptoms and true causes

Improve Phase

brainstorm solutions, evaluate effectiveness, and implement the most promising ones

Control Phase

teams develop and implement systems to monitor improved process like SOPs and regular audits

PDCA

Simpler more general approach for smaller projects or organizations new to structured improvement methodologies; Plan, Do, Check, and Act

Plan (P)

DMA of DMAIC

Do (D)

I of DMAIC

Check (C)

early part of C of DMAIC

Act (A)

later part of C of DMAIC

Total Quality Management (TQM)

emphasized customer satisfaction, continuous improvement, and an effort from all workers

quality circle

employee driven problem solving groups

Voice of the Customer (VOC)

Gathering data from surveys, focus groups, interviews to discover what customers want

cost of poor quality (COPQ)

lost customers, damaged reputation, and decreased employee moral