A Test Metric is a quantitative measure used in software testing to evaluate and track the effectiveness, efficiency and progress of testing activities. These metrics provide insights into the quality of the software, test coverage, defect trends and overall test performance.
Key Purposes of Test Metrics
- Assess Testing Progress: Helps track how much testing has been completed.
- Measure Test Effectiveness: Evaluates how well the testing process is detecting defects.
- Identify Areas for Improvement: Highlights weaknesses in the testing strategy.
- Support Decision-Making: Provides data-driven insights to improve software quality and optimise testing efforts.
Types of Test Metrics
Process Metrics (Measures the efficiency of the testing process)
- Test Case Execution Rate = (Executed Test Cases / Total Test Cases) × 100
- Test Coverage = (Number of Requirements Tested / Total Requirements) × 100
- Defect Detection Efficiency (DDE) = (Defects Detected During Testing / Total Defects Found) × 100
Product Metrics (Measures software quality)
- Defect Density = (Total Defects Found / Total Lines of Code or Function Points)
- Mean Time to Detect (MTTD) = Average time taken to identify a defect
- Mean Time to Repair (MTTR) = Average time taken to fix a defect
Project Metrics (Measures testing impact on the project)
- Test Effort Percentage = (Testing Effort / Total Project Effort) × 100
- Cost of Testing = (Total Testing Cost / Total Project Cost) × 100