ISTQB Foundation Level
  • ISTQB CTFL Syllabus 2018 V3.1
  • Author - Magdalena Olak
  • 1. Fundamentals of Testing
    • 1.1. What is Testing?
      • 1.1.1. Typical Objectives of Testing
      • 1.1.2. Testing and Debugging
    • 1.2. Why is Testing Necessary?
      • 1.2.1 Testing’s Contributions to Success
      • 1.2.2 Quality Assurance and Testing
      • 1.2.3 Errors, Defects, and Failures
      • 1.2.4 Defects, Root Causes and Effects
    • 1.3. Seven Testing Principles
    • 1.4. Test Process
      • 1.4.1 Test Process in Context
      • 1.4.2 Test Activities and Tasks
      • 1.4.3 Test Work Products
      • 1.4.4 Traceability between the Test Basis and Test Work Products
    • 1.5. The Psychology of Testing
      • 1.5.1 Human Psychology and Testing
      • 1.5.2 Tester’s and Developer’s Mindsets
  • 2. Testing Throughout the Software Development Lifecycle
    • 2.1. Software Development Lifecycle Models
      • 2.1.1. Software Development and Software Testing
      • 2.1.2. Software Development Lifecycle Models in Context
    • 2.2. Test Levels
      • 2.2.1. Component Testing
      • 2.2.2 Integration Testing
      • 2.2.3. System Testing
      • 2.2.4. Acceptance Testing
    • 2.3. Test Types
      • 2.3.1. Functional Testing
      • 2.3.2. Non-functional Testing
      • 2.3.3. White-box Testing
      • 2.3.4. Change-related Testing
      • 2.3.5. Test Types and Test Levels
    • 2.4. Maintenance Testing
      • 2.4.1 Triggers for Maintenance
      • 2.4.2 Impact Analysis for Maintenance
  • 3 Static Testing
    • 3.1 Static Testing Basics
      • 3.1.1 Work Products that Can Be Examined by Static Testing
      • 3.1.2 Benefits of Static Testing
      • 3.1.3 Differences between Static and Dynamic Testing
    • 3.2 Review Process
      • 3.2.1 Work Product Review Process
      • 3.2.2 Roles and responsibilities in a formal review
      • 3.2.3 Review Types
      • 3.2.4 Applying Review Techniques
      • 3.2.5 Success Factors for Reviews
  • 4 Test Techniques
    • 4.1 Categories of Test Techniques
      • 4.1.1 Categories of Test Techniques and Their Characteristics
    • 4.2 Black-box Test Techniques
      • 4.2.1 Equivalence Partitioning
      • 4.2.2 Boundary Value Analysis
      • 4.2.3 Decision Table Testing
      • 4.2.4 State Transition Testing
      • 4.2.5 Use Case Testing
    • 4.3 White-box Test Techniques
      • 4.3.1 Statement Testing and Coverage
      • 4.3.2 Decision Testing and Coverage
      • 4.3.3 The Value of Statement and Decision Testing
    • 4.4 Experience-based Test Techniques
      • 4.4.1 Error Guessing
      • 4.4.2 Exploratory Testing
      • 4.4.3 Checklist-based Testing
  • 5 Test Management
    • 5.1 Test Organization
      • 5.1.1 Independent Testing
      • 5.1.2 Tasks of a Test Manager and Tester
    • 5.2 Test Planning and Estimation
      • 5.2.1 Purpose and Content of a Test Plan
      • 5.2.2 Test Strategy and Test Approach
      • 5.2.3 Entry Criteria and Exit Criteria (Definition of Ready and Definition of Done)
      • 5.2.4 Test Execution Schedule
      • 5.2.5 Factors Influencing the Test Effort
      • 5.2.6 Test Estimation Techniques
    • 5.3 Test Monitoring and Control
      • 5.3.1 Metrics Used in Testing
      • 5.3.2 Purposes, Contents, and Audiences for Test Reports
    • 5.4 Configuration Management
    • 5.5 Risks and Testing
      • 5.5.1 Definition of Risk
      • 5.5.2 Product and Project Risks
      • 5.5.3 Risk-based Testing and Product Quality
    • 5.6 Defect Management
  • 6 Tool Support for Testing
    • 6.1 Test Tool Considerations
      • 6.1.1 Test Tool Classification
      • 6.1.2 Benefits and Risks of Test Automation
      • 6.1.3 Special Considerations for Test Execution and Test Management Tools
    • 6.2 Effective Use of Tools
      • 6.2.1 Main Principles for Tool Selection
      • 6.2.2 Pilot Projects for Introducing a Tool into an Organization
      • 6.2.3 Success Factors for Tools
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  1. 1. Fundamentals of Testing
  2. 1.2. Why is Testing Necessary?

1.2.4 Defects, Root Causes and Effects

The root causes of defects are the earliest actions or conditions that contributed to creating the defects. Defects can be analyzed to identify their root causes, so as to reduce the occurrence of similar defects in the future. By focusing on the most significant root causes, root cause analysis can lead to process improvements that prevent a significant number of future defects from being introduced.

For example, suppose incorrect interest payments, due to a single line of incorrect code, result in customer complaints. The defective code was written for a user story which was ambiguous, due to the product owner’s misunderstanding of how to calculate interest. If a large percentage of defects exist in interest calculations, and these defects have their root cause in similar misunderstandings, the product owners could be trained in the topic of interest calculations to reduce such defects in the future.

In this example, the customer complaints are effects. The incorrect interest payments are failures. The improper calculation in the code is a defect, and it resulted from the original defect, the ambiguity in the user story. The root cause of the original defect was a lack of knowledge on the part of the product owner, which resulted in the product owner making an error while writing the user story. The process of root cause analysis is discussed in ISTQB-CTEL-TM and ISTQB-CTEL-ITP.

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