A quantitatively managed process is a defined process that is controlled using statistical and other quantitative techniques. The product quality, service quality, and process-performance attributes are measurable and controlled throughout the project.

Quantitative objectives are established based on the capability of the organization’s set of standard processes; the organization’s business objectives; and the needs of the customer, end users, organization, and process implementers, subject to the availability of resources. The people performing the process are directly involved in quantitatively managing the process.

Quantitative management is performed on the overall set of processes that produces a product. The subprocesses that are significant contributors to overall process performance are statistically managed. For these selected subprocesses, detailed measures of process performance are collected and statistically analyzed. Special causes of process variation are identified and, where appropriate, the source of the special cause is addressed to prevent its recurrence.

The quality and process-performance measures are incorporated into the organization’s measurement repository to support future fact-based decision making.

Activities for quantitatively managing the performance of a process include the following:

·   Identifying the subprocesses that are to be brought under statistical management

·   Identifying and measuring product and process attributes that are important contributors to quality and process performance

·   Identifying and addressing special causes of subprocess variations (based on the selected product and process attributes and subprocesses selected for statistical management)

·   Managing each of the selected subprocesses, with the objective of bringing their performance within natural bounds (i.e., making the subprocess performance statistically stable and predictable based on the selected product and process attributes)

·   Predicting the ability of the process to satisfy established quantitative quality and process-performance objectives

·   Taking appropriate corrective actions when it is determined that the established quantitative quality and process-performance objectives will not be satisfied

These corrective actions include changing the objectives or ensuring that relevant stakeholders have a quantitative understanding of, and have agreed to, the performance shortfall.

A critical distinction between a defined process and a quantitatively managed process is the predictability of process performance. The term quantitatively managed implies using appropriate statistical and other quantitative techniques to manage the performance of one or more critical subprocesses so that the performance of the process can be predicted. A defined process provides only qualitative predictability.