CAPA (Corrective and Preventive Action)

CAPA stands for Corrective and Preventive Action. It is a systematic process used to investigate nonconformities, identify their root causes, and implement actions to correct issues and prevent recurrence.
See also: Root cause analysis, Corrective action, Preventive action.

CPM (Critical Path Method)

CPM, or Critical Path Method, is a project management tool that determines the longest sequence of dependent tasks to establish the minimum project duration. It helps managers schedule activities and allocate resources effectively.
See also: Project scheduling, Gantt chart.

C-chart (Count Chart)

A C-chart, also known as a count chart, is a type of control chart used to monitor the number of defects or nonconformities in a sample when the sample size remains constant. It is particularly useful for tracking quality in processes where defects can occur more than once per unit.
See also: Control chart, Attribute chart.

CR (Consumer’s Risk)

Consumer’s risk is the probability that a defective or poor-quality lot is accepted based on a sampling inspection plan. This risk quantifies the chance that a consumer may receive a substandard product despite quality testing procedures.
See also: Acceptance sampling, Type II error.

CUSUM (Cumulative Sum Control Chart)

CUSUM, or cumulative sum control chart, is a statistical tool that tracks the cumulative sum of deviations from a target value over time. It is highly sensitive to small shifts in the process mean and is used for early detection of trends and process changes.
See also: Control charts, Statistical process control.

CEN (European Committee for Standardization)

CEN is the European Committee for Standardization, an organization that develops and publishes technical standards aimed at harmonizing specifications and processes across Europe, thereby facilitating trade and innovation.
See also: European standards, ISO.

CL (Confidence Level)

The confidence level represents the degree of certainty associated with a statistical estimate or confidence interval. It indicates the probability that a given parameter falls within the specified range.
See also: Confidence interval, Statistical inference.

COPQ (Cost of Poor Quality)

COPQ stands for Cost of Poor Quality, which encompasses the economic losses resulting from defects, rework, scrap, warranty claims, and other failures in production processes. Measuring COPQ helps organizations understand the financial impact of quality issues.
See also: Quality costs, Process improvement.

Cpk (Process Capability Index)

Cpk is a statistical measure of a process’s capability to produce output within its specification limits. It accounts for both the process variability and any deviation of the process mean from the target value.
See also: Process capability, Six Sigma.

Cpm

Cpm, also known as the Taguchi capability index, measures process performance by accounting for inherent variability as well as the deviation of the process mean from the target. It provides a comprehensive view of process capability, emphasizing target alignment.
See also: Process capability index, Taguchi methods.

CP (Process Capability)

CP evaluates the inherent variability of a process relative to its tolerance or specification limits without considering the process centering. It provides an indication of a process’s potential ability to produce within the desired limits.
See also: Process capability index, Cpk.

Cpk (Process Capability Index)

CPK quantifies a process’s ability to generate output within specification limits by considering both process variability and the shift of the process mean. It is crucial for assessing process performance and consistency.
See also: Process capability, Six Sigma.

CQE (Certified Quality Engineer)

CQE stands for Certified Quality Engineer, a professional certification that validates expertise in quality engineering principles, process improvement techniques, and the implementation of quality management systems.
See also: Quality management, Six Sigma.

CSQE (Certified Software Quality Engineer)

CSQE represents Certified Software Quality Engineer, a credential awarded to professionals with specialized expertise in software quality assurance, testing methodologies, and quality engineering practices within the software development life cycle.
See also: Software testing, Quality assurance.

CSSBB (Certified Six Sigma Black Belt)

CSSBB denotes Certified Six Sigma Black Belt, a certification for professionals who lead complex process improvement projects using advanced Six Sigma methodologies and statistical tools to drive quality enhancements.
See also: Six Sigma, Process improvement, Black Belt.

CSSGB (Certified Six Sigma Green Belt)

CSSGB stands for Certified Six Sigma Green Belt, a professional credential that demonstrates an individual’s foundational knowledge in Six Sigma principles and their ability to assist in quality improvement projects.
See also: Six Sigma, Process improvement.

CSSMBB (Certified Six Sigma Master Black Belt)

CSSMBB signifies Certified Six Sigma Master Black Belt, the highest level of Six Sigma certification. It indicates mastery in strategic quality management, advanced statistical analysis, and the ability to mentor and guide other Six Sigma professionals.
See also: Six Sigma, Quality leadership, CSSBB.

CSSYB (Certified Six Sigma Yellow Belt)

CSSYB represents Certified Six Sigma Yellow Belt, a certification that provides fundamental knowledge of Six Sigma methodologies. It prepares individuals to support process improvement efforts at an introductory level.
See also: Six Sigma, Process improvement.

Cause

A cause is a factor or underlying reason that contributes to an observed problem or deviation in a process. Identifying causes is a critical step in implementing effective corrective and preventive measures.
See also: Root cause analysis, Problem solving.

Cause and Effect Diagram

Also known as an Ishikawa or fishbone diagram, a cause and effect diagram visually maps the potential causes of a specific problem. This tool aids teams in systematically identifying and organizing factors that may contribute to quality issues.
See also: Root cause analysis, Fishbone diagram.

Cause and Effect Matrix

A cause and effect matrix is a structured tool that correlates potential causes with their effects, allowing teams to prioritize issues based on the magnitude of their impact. It is commonly used to focus corrective actions on the most significant factors.
See also: Prioritization matrix, Quality planning.

Cause Analysis

Cause analysis involves a systematic investigation to identify the underlying factors leading to defects or process failures. This methodical approach enables organizations to address root causes and implement lasting improvements.
See also: Root cause analysis, Corrective action.

Cell

In a manufacturing context, a cell refers to a group of workstations or equipment configured to produce a family of similar products. Cellular arrangements are designed to enhance workflow efficiency and reduce production time.
See also: Cellular manufacturing, Lean manufacturing.

Cellular Manufacturing

Cellular manufacturing is an approach that organizes production workstations into cells dedicated to producing specific product families. This layout minimizes material handling, reduces waste, and improves overall process efficiency.
See also: Group technology, Lean manufacturing, Production cells.

Central Limit Theorem

The central limit theorem is a core principle in statistics stating that as the sample size increases, the distribution of the sample means approximates a normal distribution, regardless of the population’s original distribution. This theorem underpins many inferential statistical techniques and quality control methods.
See also: Normal distribution, Statistical inference, Sampling theory.

Centerline

The centerline is a reference line that represents the target, average, or nominal value of a process parameter on a control chart or within an engineering drawing. It serves as a benchmark for comparing actual performance against expected performance.
See also: Process mean, Target value, Control chart.

Champion

A champion is a person who leads or advocates for a particular project, change initiative, or improvement effort within an organization. Champions motivate teams, secure resources, and help overcome resistance to achieve goals.
See also: Change agent, Project sponsor, Leadership.

Change Agent

A change agent is an individual or group responsible for driving and facilitating organizational change. They work across departments to implement new processes, technologies, or cultural shifts.
See also: Champion, Change management, Organizational development.

Change Management

Change management is the discipline and structured approach to transitioning individuals, teams, and organizations from a current state to a desired future state. It involves planning, communication, and support mechanisms during change initiatives.
See also: Organizational change, Transformation, Project management.

Changeover

Changeover refers to the process of switching a production line or equipment setup from manufacturing one product to another. Effective changeover methods aim to reduce downtime and enhance productivity.
See also: Setup reduction, SMED (Single-Minute Exchange of Die), Production scheduling.

Changeover Time

Changeover time is the duration required to complete a changeover. It encompasses all activities needed to transition from one production run to another, including cleaning, adjustments, and testing.
See also: Setup time, SMED, Downtime reduction.

Charter

A charter is a formal document that outlines the scope, objectives, participants, and responsibilities for a project or process improvement initiative. It serves as a roadmap and agreement for all stakeholders.
See also: Project plan, Scope statement, Business case.

Chi-square Distribution

The chi-square distribution is a continuous probability distribution used in statistics, particularly for hypothesis testing and confidence interval estimation for variance. It is characterized by its degrees of freedom.
See also: Hypothesis testing, Statistical distributions, Variance analysis.

Chi-square Goodness-of-Fit Test

This test uses the chi-square distribution to evaluate whether observed frequencies in categorical data differ significantly from expected frequencies under a specific hypothesis.
See also: Chi-square test, Hypothesis testing, Categorical data analysis.

Chi-square Test for Independence

The chi-square test for independence assesses whether two categorical variables are statistically independent. It analyzes data in contingency tables to examine potential associations.
See also: Contingency table, Association test, Chi-square test.

Chi-square Test (χ² Test)

The chi-square test encompasses various statistical tests that use the chi-square distribution, including goodness-of-fit and tests for independence. It’s applied to determine if observed data deviate significantly from expected outcomes.
See also: Chi-square distribution, Hypothesis testing, Statistical inference.

Cluster Sampling

Cluster sampling is a sampling technique where the population is divided into groups, or clusters, and a random selection of clusters is chosen for analysis. This method is cost-effective, especially for geographically dispersed populations.
See also: Sampling methods, Stratified sampling, Survey design.

Common Cause Variation

Common cause variation refers to the inherent, natural variability found within a stable process. It is the result of small, random fluctuations that are expected during normal operations.
See also: Special cause variation, Process stability, Statistical process control.

Compliance

Compliance is the act of conforming to established guidelines, specifications, or regulatory requirements. It ensures that products, processes, or organizations meet defined standards and legal obligations.
See also: Conformity assessment, Regulatory standards, Quality assurance.

Composite Sampling

Composite sampling involves combining multiple individual samples into a single, aggregated sample for analysis. This method is often used to get an overall assessment of process performance or quality levels.
See also: Sampling plan, Aggregate analysis, Quality testing.

Concurrent Engineering (CE)

Concurrent engineering is a systematic approach to integrated product development in which different phases, such as design, manufacturing, and testing, are performed simultaneously. This method reduces time to market and improves product quality.
See also: Integrated product development, Cross-functional teams, Time-to-market reduction.

Confidence Interval

A confidence interval is a range of values, derived from sample statistics, that is believed to contain the true value of an unknown population parameter with a specified probability.
See also: Confidence level, Statistical estimation, Inferential statistics.

Confidence Level

The confidence level is the probability that a confidence interval will capture the true population parameter upon repeated sampling. It is typically expressed as a percentage, such as 95% or 99%.
See also: Confidence interval, Margin of error, Statistical inference.

Continuous Flow Production

Continuous flow production is a manufacturing process where production moves steadily without interruption through each stage of production. This method minimizes work-in-progress and enhances process efficiency.
See also: Lean manufacturing, Process optimization, Flow production.

Continuous Improvement (CI)

Continuous improvement, often abbreviated as CI and associated with the concept of Kaizen, is an ongoing effort to refine processes, products, or services incrementally. It emphasizes small, continual changes to achieve significant overall benefits.
See also: Kaizen, Lean, Total Quality Management (TQM).

Continuous Sampling

Continuous sampling is a quality control method where each item or a constant stream of items is examined without interruption rather than using random sampling techniques. It can lead to quicker detection of process issues.
See also: 100% inspection, Statistical process control, Quality monitoring.

Continuous Sampling Plan

A continuous sampling plan is an inspection procedure that involves evaluating every item over time or after each production lot, providing ongoing statistical data to assess process performance.
See also: Acceptance sampling, Quality control plan, Statistical sampling.

Continuous Variable

A continuous variable is one that can assume an infinite number of values within a given range. Examples include measurements like temperature, time, or weight.
See also: Discrete variable, Data types, Statistical analysis.

Control Chart

A control chart is a graphical tool used in statistical process control to monitor process behavior over time. It displays process data alongside control limits to help detect variation trends and signal when a process may be out of control.
See also: Process monitoring, Control limits, SPC.

Control Limits

Control limits are statistically determined boundaries on a control chart that define acceptable levels of variation in a process. Data points falling outside these limits typically indicate that special causes are affecting the process.
See also: Control chart, Process capability, Statistical process control.

Control Phase

The control phase is the final stage in process improvement methodologies (such as Six Sigma) where measures are put in place to sustain the gains achieved. It involves monitoring the process, establishing standard operating procedures, and ensuring long-term stability.
See also: Process improvement, Implementation, Sustainment.

Control Plan

A control plan is a documented strategy that outlines the critical parameters, monitoring methods, responsibilities, and corrective actions required to maintain a process’s performance at the desired level.
See also: Quality plan, Process management, Control phase.

Controlled Variation

Controlled variation refers to the variability in a process that is understood, managed, and maintained within limits set by design specifications. It contrasts with uncontrolled or special cause variation.
See also: Common cause variation, Process capability, Statistical control.

Conformity Assessment

Conformity assessment is the evaluation process used to determine whether a product, service, or system meets specified standards or regulatory requirements. It may include testing, inspection, certification, and accreditation activities.
See also: Compliance, Certification, Quality assurance.

Consensus

Consensus is the general agreement reached by a group after discussion and consideration of different viewpoints. In quality and project management, consensus ensures that decisions and actions have collective support.
See also: Stakeholder alignment, Decision-making, Collaboration.

Consumer

A consumer is the end-user or purchaser of a product or service. In quality management and market research, consumer satisfaction and feedback are critical metrics that inform product improvements and service enhancements.
See also: Customer, End-user, Market research.

Consumer’s Risk (β Risk / Beta / Consumer’s Risk)

Consumer’s risk, also known as β risk or beta, is the probability that an inspection or sampling procedure will incorrectly accept a lot or process that does not meet quality standards. In other words, it is the risk that a defective product or batch passes through quality inspection and reaches the consumer.
See also: Producer’s risk, Type II error, Acceptance sampling

Continuous Data

Continuous data refers to measurements that can assume any value within a given range. These data are measurable with an infinite level of precision (within the limits of the measuring instrument) and include examples such as temperature, weight, or time.
See also: Discrete data, Measurement scales

Contract Review

A contract review is the systematic examination of a contract's terms, conditions, and agreements to ensure they meet the required standards and obligations before execution. This process helps identify potential risks, ambiguities, or compliance issues that may need to be resolved.
See also: Contract management, Due diligence

Corrective Action

Corrective action involves steps taken to eliminate the causes of an observed nonconformity, defect, or undesirable situation in a process. The focus is on identifying the root cause and implementing changes to prevent a recurrence.
See also: Corrective and Preventive Action (CAPA), Root cause analysis

Corrective Action Request (CAR)

A Corrective Action Request (CAR) is a formal document issued when a nonconformance or quality issue is detected. It outlines the problem, initiates a review, and calls for the identification and implementation of corrective measures to resolve the issue.
See also: Corrective action, CAPA

Cost of Poor Quality (COPQ)

Cost of Poor Quality (COPQ) represents the expenses that arise as a result of producing defects or failures in a product or service. These costs include rework, scrap, warranty claims, and other losses linked to quality issues.
See also: Cost of Quality, Process improvement

Cost of Quality (COQ)

The Cost of Quality (COQ) encompasses all the costs incurred to ensure that products or services meet quality standards. It includes both the costs of achieving conformance (such as prevention and appraisal costs) and the costs associated with nonconformance (such as failure costs).
See also: Quality costs, COPQ

Cost-Benefit Analysis

Cost-benefit analysis is a systematic approach used to compare the strengths and weaknesses of alternatives. By quantifying both the costs and the benefits of a project or decision, organizations determine which option offers the best financial or practical advantage.
See also: Financial analysis, Decision-making

Count Chart (c-chart)

A count chart, or c-chart, is an attribute control chart used to monitor the number of defects or nonconformities in an area of opportunity when the sample size remains constant over time. It helps track process performance based on defect counts.
See also: U-chart, Control charts

Count per Unit Chart (u-chart)

A count per unit chart, or u-chart, is used to monitor the number of defects per unit when the sample size may vary. It provides information on the defect rate, adjusting for differences in the number of units inspected.
See also: C-chart, Attribute control charts

Covariate

A covariate is an independent variable that may influence or predict the outcome of a study or process. In the context of statistical analyses within quality management, covariates are considered to adjust or control for effects that might confound the primary relationship under investigation.
See also: Independent variable, Regression analysis

Coverage Factor

The coverage factor is a multiplier used in uncertainty analysis. When applied to the standard uncertainty of a measurement, it yields the expanded uncertainty, typically corresponding to a desired confidence interval (for example, a factor of 2 is often used to approximate a 95% confidence level).
See also: Measurement uncertainty, Confidence interval

Critical Incident

A critical incident is an event that has a significant impact—either positive or negative—on a process, operation, or system. In quality and safety contexts, such incidents are analyzed to determine their causes and to prevent future occurrences.
See also: Incident analysis, Root cause analysis

Critical Processes

Critical processes are those operations or procedures within an organization that have a substantial impact on the quality, safety, or performance of the final product or service. Because of their importance, these processes are subject to enhanced control and monitoring.
See also: Process mapping, Key process analysis

Critical to Quality (CTQ)

Critical to Quality (CTQ) attributes are the essential measurable characteristics of a product or process that must be met to satisfy customer requirements. Identifying CTQs helps organizations focus on what is most important from a quality perspective.
See also: Quality Function Deployment (QFD), Customer requirements

Cross-Functional

The term cross-functional refers to initiatives, processes, or teams that involve participation from multiple functional areas within an organization. This approach leverages diverse expertise to foster comprehensive problem solving and innovation.
See also: Interdisciplinary collaboration, Collaborative teams

Cross-Functional Team

A cross-functional team is composed of members from various departments or specialized areas within an organization who collaborate on projects or problem-solving initiatives. Such teams provide a broad range of skills and perspectives, enhancing decision-making and process outcomes.
See also: Team collaboration, Interdepartmental teams

CR (Consumer’s Risk)

CR is an abbreviation for Consumer’s Risk, which is the same concept as described above. It is the likelihood that a defective lot or process will pass the inspection criteria, thereby putting substandard products into consumers’ hands.
See also: Consumer’s risk, β risk, Acceptance sampling

CUSUM (Cumulative Sum) Chart

A CUSUM chart is a type of control chart that plots the cumulative sum of deviations from a target value over time. It is especially sensitive to small shifts in the process mean, making it a powerful tool for early detection of process changes.
See also: Control charts, Statistical Process Control (SPC)

Cycle Time

Cycle time is the total elapsed time required to complete a process from start to finish. It includes all aspects such as processing time, waiting time, and any delays, and is a key metric used to evaluate process efficiency and throughput.
See also: Lead time, Throughput time