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How to Gather Customer Data through a questionnaire?

Let us learn how to gather customer data. A well-defined goals are the best way to assure a good questionnaire design. When the goals of a study can be expressed in a few clear and concise sentences, the design of the questionnaire becomes considerably easier.

gather customer data

To effectively conduct a customer survey through a questionnaire, follow these guidelines:

  • Keep your questionnaire short because long questionnaires get fewer responses when compared to short questionnaires.
  • Include experts and relevant decision makers in the questionnaire design process.
  • Formulate a plan for doing the statistical analysis during the design stage of the project.
  • Questionnaires reflect first impressions. The respondents first impressions come from the cover letter. Provide a well-written cover letter.
  • Give your questionnaire a title that is short and meaningful to the respondents.
  • Include clear and concise instructions on how to complete the questionnaire. 
  • Use short sentences and basic vocabulary.
  • Begin with a few interesting items. If the first items are too boring, there is little chance that the questionnaire will be completed.
  • Use simple and direct language in the questions so they are clearly understood by the respondents.
  • Leave adequate space for respondents to make comments. One criticism of questionnaires is their inability to retain the connotation of responses.
  • Place the most important items in the first half of the questionnaire.  
  • Hold the respondents’ interest. One way to keep a questionnaire interesting is to use a variety of questions.
  • Provide incentives as a motivation for a properly completed questionnaire.
  • Make it convenient. The easier the questionnaire, the better the response.
  • Use professional production methods for the questionnaire, such as desktop publishing.
  • The final test of a questionnaire is to try it on representatives of the target audience to identify any problem areas.
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What tools are used in Define Phase of six sigma?

six sigma define phase tools

A Six Sigma team uses a number of tools in the Define phase to identify and define problem areas or opportunities for improvement. The tools include:

  • Project charter is a  document that provides a clear, concise description of the business needs that a project is intended to address. It not only makes a project official, but also gives Yellow Belts, Green Belts, or Black Belts the authority to lead the project and draw on organizational resources as needed. The project charter documents the expected results.
  • SIPOC diagram is a  high-level process map that is used to identify and define all the relevant elements that are necessary for improving a process before actual work begins. It is an acronym of these elements: Suppliers, Inputs, Processes, Outputs, and Customers. The SIPOC diagram helps process improvement teams understand the purpose and the scope of a process before they begin to measure or improve it. It is also called COPIS to emphasize that the entire process starts with customers. COPIS is an acronym of Customers, Outputs, Processes, Inputs, and Suppliers.
  • Affinity diagram is a diagram that is used to organize different ideas that are generated in brainstorming sessions into meaningful groups.
  • Multi-Generational Planning (MGP) is an approach that breaks projects into manageable phases. Each phase is called a generation, and therefore the approach is called MGP. Breaking down projects logically and rolling them out in a phased manner helps the process development team envision the various stages of a product or service. In the evolution of products or services, different functionalities are added several times in each phase of MGP. MGP helps you manage project scopes better in process improvement projects.
  • Stakeholder analysis is an analysis used by quality improvement teams for identifying and evaluating people who will influence the outcome of a project to ensure that their interests are addressed. Knowing the effect that stakeholders will have on a project also helps in anticipating potential problems and devising strategies to handle them effectively.
  • Communication plan is a written document that describes how different stakeholders and interested parties will be informed about the objectives of a project, the means of accomplishing these objectives, the tools to be used, improvements, solutions and how they impact stakeholders, project benefits, progress made, and the timeline.
  • VOC analysis is used to understand customer requirements so that an organization can provide products and services that meet these requirements. It delivers products and services that satisfy customers that helps organizations survive in a highly competitive market.
  • Kano analysis is an analysis that measures the extent to which a product or service satisfies the requirements and expectations of customers. In other words, it defines the customers’ requirement priorities. Professor Noriaki Kano developed Kano analysis, as it was named
    after him. The Kano model classifies product attributes based on how they are perceived by customers. It classifies customer requirements as mandatory requirements and delights. These classifications are useful for a customer-driven organization to make design decisions on its product.
  • Quality Function Deployment (QFD)is a  structured approach followed by customer-driven organizations to transform customer requirements into product specifications. QFD provides an insight into the whole design of a product, thereby eliminating production problems that may arise during manufacturing.
  • RACI matrix is a tool used for clarifying roles, responsibilities, and authority in teams involved in a business process task. RACI is an acronym of the four responsibilities used, namely Responsible, Accountable, Consulted, and Informed.
  • Project prioritization matrix is a  tool used during brainstorming sessions for evaluating various issues against different criteria and prioritizing the issues. This helps identify issues that must be solved first to eliminate problems and improve processes.
  • Pareto chart is a bar chart that displays various categories of problems in a project by the frequency of their occurrence. It is named after its creator, Vilfredo Pareto, a 19th century economist. The objective of using a Pareto chart is to narrow down the primary causes of problems and focus efforts on tackling the most important causes. The Pareto chart is also known as the 80-20 chart.

These tools are used during the Define phase to understand selected projects better.


Both DFMEA and PFMEA have similar principles and follow identical steps. Both involve identifying potential failures, their impact, and corrective measures to be taken for reducing or eliminating these potential failures.

However, DFMEA and PFMEA differ in a few aspects, such as their focus and the stage in which these two analyses are done.

DFMEA focuses on potential failures related to product design changes. The main focus is on finding potential failures that can result in malfunctions and safety hazards while using the product. It is also applied to identify potential causes that may curtail the life of the product. It  must be conducted throughout the entire design process, starting at the preliminary design as soon as the design concept has been selected to the production.

PFMEA focus on potential failures associated with processes and changes to them. The main focus is on finding potential failures related to a process that can affect the quality of a product or cause safety or environmental hazards and result in customer dissatisfaction. It is also applied to identify potential causes that reduce the reliability of the process.



  • DFMEA: On potential failures related to product design changes
  • PFMEA: On potential failures associated with processes and changes to them

Y shaped matrix

Fig: A Y-shaped matrix that summarizes the requirements for different models of photocopiers

The Y-shaped matrix is a matrix diagram that relates three sets of elements where one set is related to the other two sets in a circular manner. . It can be formed by bending the columns of sets A and B in the T-matrix in such a way that there is an interrelation between the elements of these two sets.


Matrix diagrams can be sorted into several types depending on the number of data sets being compared.

  • L-shaped Relates two sets of elements to one another or a single set of elements to itself.
  • T-shaped Relates three sets of elements where there is no relation between the two sets that are related to a common set.
  • Y-shaped Relates three sets of elements where one set is related to the other two sets in a circular manner.
  • C-shaped relates three sets of elements simultaneously.
  • X-shaped relates four sets of elements.
  • Roof-shaped relates one set of elements to itself.


A matrix diagram, also called a matrix chart, is a management and planning tool used for identifying relationships between two to four groups of elements or among elements in a single group. The elements in different groups are placed in rows and columns and relationships among them are analyzed by the team. Symbols indicating the strength of the relationships are then entered in the cell where the row and column of the two elements intersect. If there is no relationship, then it is left blank. Because matrix diagrams help you analyze data, they are also extensively used in the Measure and Analyze phases of the DMAIC methodology.

  • Relationships among different sets of items by comparing them, especially many-to-many relationships among them instead of one-to-one relationships.
  • The strength of the relationship between different sets of items qualitatively.
  • And, the success of a process that generates one set of items from another set of items.


In the previous topic, you created a tree diagram. Key issues identified must also be sorted in the order of their importance. A prioritization matrix helps determine the order for dealing with different issues or selecting solutions according to their relative importance. In this topic, you will create a prioritization matrix to identify crucial issues that require immediate attention.

You must prioritize key issues identified according to their importance to determine which issues or solutions are the most critical and need to be addressed first. Using a prioritization matrix, you can determine such crucial areas where Six Sigma projects need be implemented to improve your business processes.

What are Prioritization Matrices?

A prioritization matrix is a tool used for determining the most important issues or solutions. This tool can be used for any prioritization activity. In a Six Sigma project, it can be used for filtering or prioritizing either causes or solutions. For example, the cause-and-effect matrix is a prioritization matrix used for prioritizing causes, while the criteria-based matrix is used for prioritizing solutions.

Whatever the matrix, the procedure used for prioritization is the same. The Six Sigma team identifies different criteria to be used for measuring different solutions. The relative importance of each criterion is determined and a numerical value indicating the weight of each criterion is entered in a column. Ratings are then assigned to the solutions against different criteria. The different solutions are scored against the identified criteria. Each rating is then multiplied by the criteria weights to obtain the weighted scores. The weighted scores are then added to find the cumulative value. The option with the highest total value is regarded as the option with the highest priority.

Prioritization Matrix

Fig: A sample prioritization matrix

What are the use of Prioritization Matrices?

  • Prioritizing complex issues involving several criteria against which the issues are assessed.
  • Assigning scores to the criteria or issues when data is available.
  • Choosing key areas to be focused upon immediately.
  • And, garnering team support and approval of crucial issues.

How to Create a Prioritization Matrix?

To create a prioritization matrix for determining key areas where Six Sigma projects need be implemented first:

  1. Gather the team members required to participate in the exercise.
    1. It is not necessary to limit the team to only the project team members.
    2. Involve all stakeholders who would have influence on the items to be prioritized.
    3. Ideally, the size of the team should be around eight.
    4. Agree upon the scope and the duration of the exercise because there is a tendency to drift from the main subject of interest, which may consume more time.
  2. Identify criteria against which the items to be prioritized can be weighed. Select the criteria according to your business and the nature of the process.
  3. Assign weights to the criteria on a scale of 1 to 10.
    1. Use an ascending scale while assigning the weight. Usually, the higher the better.
    2. Draw consensus within the team on the weights.
  4. Assign ratings for each item to be prioritized against different criteria on a scale of 1 to 10. Alternatively, the team can also pick solutions one by one and gather votes for each criterion. Members who agree that a solution fits a particular criterion vote for it. Ensure that necessary information is available to the team before voting.
  5. Compute the total score for each item.
    1. Multiply the rating for an item by the weight.
    2. Add the total scores for each item.
  6. Continue doing this for every criterion of all the items.
  7. Shortlist the items with higher scores for implementation.


An interrelationship digraph, also called a relations diagram or network diagram, is a tool that depicts relationships among different elements, areas, or processes through a network of boxes and arrows. It is usually used by Six Sigma teams to understand cause-and-effect relationships among different factors of a problem.



The metrics of a Six Sigma project reflect customer needs and ensure that the internal metrics of the organization are achieved. The selection of project metrics is one of the crucial elements in the Define phase of the Six Sigma methodology.

Six Sigma project metrics can be categorized into primary metrics and secondary metrics.

Primary Metrics

A primary metric, also called a project CTQ, is a CTQ measure that is used to monitor project progression and success. It is the reference point throughout the Six Sigma project. Ideally, project CTQs should have direct impact on customers. For any Six Sigma project, the primary metrics should be:

  • Tied to the problem statement and objective of the project.
  • In possession of an operational definition.
  • Measurable, simple, and expressed in the form of an equation.
  • Aligned to business objectives.
  • Tracked on hourly, daily, weekly, and monthly basis.
  • Expressed graphically over time with a run chart, time series, or control chart.
  • And, validated with a Measurement Systems Analysis (MSA).

Some of the primary metrics of a Six Sigma project include customer satisfaction, on-time delivery of products, final product quality, and less costly products.

Secondary Metrics

A secondary metric, also known as a consequential metric, is a project metric that you do not want to sacrifice at the expense of primary improvements in a process. These metrics ensure that the process is improving and not shifting one metric at the expense of another. It means that the secondary metrics have a relationship with the primary metrics of a Six Sigma project. Therefore, the primary goal of a Six Sigma project will be to move the primary metrics, but ensure that secondary metrics do not deteriorate or stay constant. Some of the secondary metrics include cycle time, volume shipped, inspection data, and rework hours. These metrics should not be sacrificed to achieve the primary metrics such as customer satisfaction, on-time delivery of products, and final product quality.


A project charter is a contract between a Six Sigma project team and a sponsor. It provides a clear, concise description of the business needs that the project is intended to address. Any changes to the critical elements of a project charter need prior approval from the sponsor and consensus from the team members.

A completed sample project charter is available for download.

Click here to download here


Six Sigma projects are primarily focused on customers. The other areas that Six Sigma projects focus on are:

  • Improving the performance of Critical to Quality (CTQ)
  • Reducing the number of complaints from customers.
  • Reducing in-process or internal defects.
  • Reducing warranty claims.
  • Improving survey and customer research scores.
  • Capturing feedback from staff members effectively.
  • Increasing profits and revenue.
  • Improving audit scores.
  • Improving process performance and dashboard metrics.
  • And, having better growth than competitors.


Some of the major attributes of CTQ include:

  • A single meaning for each metric across all geographic locations.
  • Defining the process owners who are responsible for tracking the CTQ.
  • Clearly defined defects and opportunities in the process.
  • A consistent measurement system to provide accurate and precise measurements.
  • And, it must be derived from the VOC so that it provides a strong linkage to the VOC.

Affinity Diagrams

An affinity diagram is a tool that is used to organize a large number of ideas, opinions, and issues and group them based on their relationships. Affinity diagrams are generally used for categorizing ideas that are generated during brainstorming sessions and can be particularly useful for analyzing complex issues.

The steps for creating an affinity diagram can include:

  1. Generating ideas through brainstorming.
  2. Displaying the ideas randomly.
  3. Sorting the ideas into groups.
  4. Creating header cards for each group to capture the essential links among the ideas in each group.
  5. And, drawing the affinity diagram by writing the problem statement at the top and the headers with their respective groups of ideas below the problem statement.
  6. An affinity diagram helps in sorting and grouping customer requirements.


To gather the VOC, effective methods for accurately capturing customer requirements are required. Several methods are available to capture the VOC.

  • Interviews are used to gather information from stakeholders by talking to them directly. Interviews aid in identifying and defining features and functions or desired project deliverables.
  • Focus groups is a trained moderator-guided interactive discussion that includes pre-qualified stakeholders and subject-matter experts (SMEs) to elicit their expectations and attitudes toward the proposed product, service, or result of the project.
  • Facilitated workshops is an interactive group-focused sessions that bring together key cross-functional stakeholders to define the project or product requirements. It is a primary technique to define cross-functional requirements and reconcile stakeholder differences to the project. Facilitated workshops occur much faster than individual discussions.
  • Questionnaires and surveys is another method where written sets of questions designed to quickly gather information from a broad audience.
  • Mystery shopping commonly performed in retail industries. This method is used to measure the quality of a service by gathering specific information about the product or service. This method is performed by mystery shoppers who introduce themselves as customers and perform specific customer-related tasks, such as purchasing a product and raising questions and complaints about the product.
  • Observations are a direct way of viewing individuals in their work environment or while using the product to identify the project or product requirements. Also referred to as job shadowing.
  • Market research is an organized effort to gather information about the current trends in an industry and also Field reports is a formal report documented by field engineers or other on-site personnel who gather required information about events that occur during their field work.
  • Customer feedback and complaints data are used to gather customer requirements. This method also involves gathering customer feedback about the quality of a product or service. The consolidated list of feedback from customers is referred to as complaints data.
  • Reliability data is a source of information that helps in analyzing the reliability of a product or process. By gathering this data, you can plan strategies to gain a reputation with customers as a reliable provider of services.
  • Staff feedback is another method of gathering opinions from staff who interact with customers directly or who possess knowledge about customers and their expectations. This information is captured by conducting surveys, brainstorming sessions, and other information gathering sessions.


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