An Empirical Study on Testability Measurement of Object Oriented Software

Testability has always been a difficult exercise and its accurate estimation or assessment a complex exercise. Most of the studies quantify testability or more specifically the attributes that have influence on software testability but at the implementation level. A decision to transform the design in order to improve software testability after implementation has started may be very error prone and expensive. While estimating testability early in the software development life cycle may significantly reduce the overall development cost. In this paper Testability has been recognized as a major factor to object oriented software quality and importance is being drawn to measure design testability, near the beginning in the software development process. Study identified effectiveness and flexibility are the major factors that affect overall testability at design phase. The identified testability factors are to be correlated with the object oriented design characteristics. After successfully establishing the relationship, study developed Testability Measurement Model for Object Oriented Design. Subsequently testability model has been empirically validated and contextual interpretation has been performed using try out software projects.