The theoretical framework that will be used in this study is the Input-Process-Output Model. In the IPO model, a process is viewed as a series of boxes (processing elements) connected by inputs and outputs. Information of material objects flow through a series of tasks or activities based on a set of rules or decision points. Flow charts and process diagrams are often used to represent the process. What goes in is the input; what causes the change is the process; and what comes out is the output (Harris and Taylor, 1997).
Figure 1 illustrates the basic IPO model:
Figure 1. The IPO model
The IPO model will provide the general structure and guide for the direction of the study. Substituting the variables of this study on the IPO model, the researchers came up with the conceptual framework.