A periodic time frame can be used to arrange for Control Limit and Center Line calculations with good SPC implementation in a process.

The statement is correct. A fundamental principle of Statistical Process Control (SPC) is the monitoring of a process over time to ensure it remains in a state of statistical control. This is accomplished using control charts, which require data to be collected in rational subgroups at regular, periodic intervals (e.g., hourly, per shift). This time-ordered, periodic data collection is essential for calculating the Center Line and Control Limits and for detecting trends, shifts, or patterns that indicate the presence of special cause variation. A good SPC implementation depends on this systematic approach.

B. False: This is incorrect. SPC fundamentally relies on time-ordered data collected periodically. A non-periodic or random sampling scheme would make it impossible to effectively analyze process performance over time and detect meaningful trends or shifts.

1. Montgomery, D. C. (2013). Introduction to statistical quality control (7th ed.). John Wiley & Sons. In Chapter 6, Section 6.2, "Rational Subgroups," the text explains that subgroups are samples collected over a short time interval to represent a "snapshot" of the process, and these subgroups are then selected at periodic intervals to construct the control chart. This time-based structure is critical for chart interpretation.

2. MIT OpenCourseWare. (2004). 2.854 Introduction to Manufacturing Systems, Lecture 10: Statistical Process Control. Massachusetts Institute of Technology. Retrieved from https://ocw.mit.edu/courses/2-854-introduction-to-manufacturing-systems-fall-2004/resources/lec10/. The lecture notes state, "Samples of size n are taken from the process periodically in time," directly confirming the principle described in the question.

3. Antony, J., & Taner, T. (2003). A conceptual framework for the effective implementation of statistical process control. The TQM Magazine, 15(3), 151-159. https://doi.org/10.1108/09544780310469273. This peer-reviewed article discusses critical success factors for SPC implementation, implicitly and explicitly referencing the standard practice of periodic data collection for monitoring process behavior over time.