DMAIC expands to Define, Measure, Analyse, Improve and Control, whereas DMADV is an abbreviation for Define, Measure, Analyse, Design and Verify. Keeping aside the initial three letters of the two methodologies which have common meanings, the primary difference between them lies in the manner in which the last two steps take place.
This means that if the firm is using DMAIC, the improvement and control steps emphasizes determining the means to readjust and control the process. In DMADV, the design and verify steps involve redesigning the process, so as to suit the needs of the customer.
What is Six Sigma?
A quality measure that works toward near perfection. It attempts to reduce variations in the process that causes defects. The underlying philosophy behind six sigma is to reduce process output variation. For this, we use a common metric to compare the performance of the process in terms of variability with different processes, which is Defects Per Million Opportunities (DPMO).
The objective of this methodology is to substantially improve the process as well as the product design through a systematic process improvement strategy. The focus is on quality management, improvement and measurement. Further, DMAIC and DMADV are the two methodologies of six sigma
Also Read: Difference Between Lean and Six Sigma
This post elaborates on the differences between DMAIC and DMADV. Let’s have a look.
Content: DMAIC Vs DMADV
|Basis for Comparison||DMAIC||DMADV|
|Meaning||DMAIC is a six sigma methodology which attempts to improve the existing process.||DMADV is another six sigma methodology that seeks to design new or existing processes.|
|Type of Process||Reactive Process||Proactive Process|
|Focuses on||Process focused||Customer-focused|
|Team Requirement||Small Team||Large Team|
|Time Horizon||Short to Medium-term||Long term|
|Used when||Continuous improvement is required||Reengineering is required|
|Tools used||Statistical and quantitative tools||Qualitative tools|
|Implemented when||Incremental change is needed||Evolutionary change is needed|
What is DMAIC?
DMAIC is a six sigma model which the companies use to make improvements in the existing processes that are underperforming. That is their performance is not enough to meet the standard or level, as measured against critical to ‘x’ requirements. Here ‘x‘ denotes critical customer or stakeholder requirements in terms of:
Further, DMAIC is a fact-based, systematic and scientific methodology. It removes those steps which are not productive. Also, it concentrates on measurements and applies technology to make improvements. In this, improvements are made in quality on a project-by-project basis.
This step involves:
- Identification of stakeholders
- Definition of problem
- Ascertainment of requirement
- Establishment of goals for process improvement that are consistent with the needs of the stakeholders and the strategy of the organization.
Further, the improvement project is devised and planned. To work on this project a team is constituted and management support along with the required inputs are provided.
At this stage, the team will map out the existing process. Thereafter, determination of the critical to x characteristics of the process in which there is a need for improvement takes place. And for this, metrics for measuring the CTx characteristics are chosen, designed and confirmed.
Besides, a data collection plan is made and data is collected from the existing process to ascertain the baselines and levels of variation for each metric that is chosen. Further, the information is helpful in the determination of the capability of the current process. As well as it defines the benchmark performance levels of the current process.
To analyse the data, the team uses statistical tools right from the previous step. This is to completely understand the impact that each input variable has on the process and the consequent outputs.
Further, the team will perform a gap analysis to assess the variance between current performance and desired performance. On the basis of these evaluations, identification and validation of the fundamental cause of the problem and/or variation in the process occurs. This step aims at understanding the process in such a manner that it is easy to explore multiple improvement actions, during the improvement stage.
This step involves consideration of various approaches to solve the problem and reduce the variations in the process. After that, the team:
- Assesses Impact of cost and benefit
- Determines risk of various alternatives
- Carries out trade-off studies
Then the team agrees upon a particular approach which is the best one and makes plans to implement improvements. Further, prior to the implementation of the plan, the team must take the approval of the relevant authority. Also, a pilot study is undertaken to test the solution. And if the pilot study becomes successful, then the solution is implemented to the whole organization. But if the pilot study comes out as unsuccessful, repetition of suitable DMAIC steps as per the requirement takes place.
In this step, standardization and regulation of the process that has been improved occur. Then, it implements controls to ensure that improvement gains are sustained in future also. It covers:
- Selection of key metrics
- Definition of key metrics
- Implementation of key metrics
This will help in observing the process or the product to look for any future conditions that are not under the control of the management.
What is DMADV?
DMADV is a model of six sigma. The alternative name for DMADV is DFSS i.e. Design for Six Sigma. It tends to define new processes and products at Six Sigma quality levels. This model is also applied at the time of the optimizing current process or product that does not reach specified quality levels.
At this step, the establishment of goals relating to the design activity takes place. While determining goals, one must keep in mind the needs of the shareholder and alignment with the organizational strategy. This step is the same as the define step in the DMAIC model.
It involves the ascertainment of the critical to x characteristics of the novel product or process. After that, metrics for measuring the critical to x characteristics are selected, designed and confirmed. And then the determination of the data collection plan for each selected metric takes place.
In this step, the team will consider multiple approaches to designing the novel product or process. And then assessment with regard to cost, benefits, impacts, and risk of each alternative is performed by the team along with the study of trade-offs. After that, the team comes up with the best approach.
The creation of advanced and detailed designs occurs at this stage. Along with that, the implementation and optimization of these designs take place. Also, the team develops a number of plans for the verification of the designs.
Verification of a new process or product takes place to ensure that it fulfils the needs of the stakeholders. It covers simulations, pilot studies or tests. After that, the new process or product design is implemented the team will develop a strategy for project handoff to the owners of the process.
Key Differences Between DMAIC and DMADV
The pointers are given here explain the difference between DMAIC and DMADV:
- DMAIC process is an improvement approach for existing processes that fall below the desired level and are seeking improvements on an incremental basis. On the other hand, DMADV is another improvement approach that aims to introduce new processes or products at Six Sigma quality levels. Further, we can also use it for current processes if they need additional improvement along with incremental ones.
- While DMAIC is a reactive process, DMADV is a proactive process.
- While DMAIC focuses on the process, the focus of DMADV is on the customer.
- To implement DMAIC we require a small team. Whereas DMADV requires a large team for its implementation.
- The time frame for the implementation of DMAIC is short to medium time frame. But the time frame for implementation of DMADV is long term.
- DMAIC is process improvement driven, i.e. we use this method if the firm needs continuous improvement. Whereas DMADV is for designing new products or services. That is to say, we use DMADV when there is a need for reengineering.
- DMAIC rests upon a corrective approach. However, DMADV is a preventive approach.
- In DMAIC the team uses statistical or quantitative tools. Conversely, in DMADV the team uses qualitative tools.
- We use DMAIC when there is a need for incremental change. But if the change required is evolutionary in nature then we use DMADV.
|Measurement systems analysis|
|Process sigma calculation|
|Improve||Design of experiments|
|Standard operating procedures|
In a nutshell, the implementation of the scientific cycle in the six sigma methodology is systematized in two innovative schemes, which are DMAIC and DMADV.