Canadian Health Information Management Association Practice Exam

What type of variation is caused by factors outside of a system?

1. a. common-cause variation.

2. b. input/output.

3. c. processes.

4. d. special cause variation.

The correct answer is: d. special cause variation.

Special cause variation refers to variations that arise from external factors that are not inherently part of the process or system. These variations are typically identifiable and can often be traced back to specific, sporadic influences that disrupt the normal operation of the system. For instance, a factory might experience a sudden spike in defects due to a malfunctioning machine or a temporary shortage of materials, which are not regular occurrences. Understanding special cause variation is crucial because it suggests that the system can be improved or corrected by addressing these external influences. In contrast, common-cause variation is inherent to the system and represents the natural fluctuation that occurs during the normal functioning of a process. Identifying special cause variation allows organizations to implement targeted interventions, whereas managing common-cause variation often involves more systemic changes to reduce the variability that is an integral part of the operation. The other choices do not correctly capture the essence of external influences on a system in the same way that special cause variation does. Input/output focuses more on the transfer of information or materials across processes rather than variations in performance arising from outside factors. Processes refer to the series of actions involved in operating a system but do not specifically denote the type of variation in question. Therefore, the identification of special cause variation as the correct answer