Six Sigma is a data-driven, customer focused and results-oriented methodology which uses statistical tools and techniques to systematically eliminate the defects and inefficiencies to improve processes. It is a systematic method to measure and analyze the business processes to identify critical factors affecting business results, thereby improving the processes and establishing controls around the improved processes.
The term ‘six sigma’ comes from statistics and is used in statistical quality control (SQC) which evaluates process capability i.e. the numerical measure of the ability of a process to meet the customer specifications. It was originated from terminology associated with manufacturing which refers the ability of manufacturing process to produce a very high proportion of output within specifications. The sigma rating of a process indicates its yield or percentage of defect-free outputs it produces. A six sigma process is the one which produces 99.99966% statistically defect-free outputs which is equivalent to 3.4 defects per million opportunities (DPMO).
Six sigma uses a set of quality management and statistical methods and creates a team of experts within the organization (Executive Leadership, Champions, Black belt, Green Belt, Yellow Belt etc.) having specific skill sets required to carry out the six sigma project. Each six sigma project carried out within an organization follows a defined sequence of phases with quantifiable value targets e.g. reduction in process cycle time, reduce cost, increase in quality rating/ customer satisfaction index, reduction is defect rate.
Road Map of a Six Sigma project:
- Identify the areas of improvement
- Define the problem statement and goals for improvement in quantifiable terms (i.e. which can be measured numerically)
- Determine the resources required for the project
- Formulate a project deliverables timeline in a phased manner
- Establish performance parameters/ metrics
- Gather baseline information about the process
- Validate measurement system for the process output (Y)
- Examine the data collected in the earlier phase to determine a prioritized list of sources variation
- Explore potential causes (potential X’s for causation) and determine the impact of each X has on the response Y
- Determine the optimum level of vital few X’s
- Validate measurement system for X’s
- Verify process improvement
- Develop control mechanism to ensure sustenance of the improved process
Some benefits of Six Sigma are given below:
- Six Sigma helps companies to reduce cost and improve productivity
- Six Sigma improves quality of projects output by reduction of inefficiencies and defects
- Six Sigma increases customer satisfaction and loyalty
- Certified Six Sigma Professionals can help increasing ROI significantly