The 4M Change Management Framework in Medical Device Regulation

Understanding the 4M Framework

The 4M framework is a method for analyzing processes and systems by considering four essential elements: Man (人), Machine (機械), Material (材料), and Method (方法). The acronym “4M” is derived from the first letter of each element in English.

Man (People)

Man refers to the operators and staff working on the production floor. Maintaining consistent product quality requires continuous maintenance and management of the workforce’s capabilities and competencies.

In manufacturing processes, specialized technical skills and expertise are essential for machine operation and control, material selection and procurement, and implementation of accurate and timely procedures. To ensure quality, organizations must analyze and understand each operator’s and staff member’s skill level and aptitude, manage them effectively, and assign appropriately qualified personnel to specific tasks based on their competencies.

Since machinery, materials, and methods all depend on human execution, Man represents the fundamental foundation of the 4M framework and is considered its most critical element.

Machine (Equipment and Facilities)

Manufacturing production floors employ various machines and facilities to enable manufacturing operations. To maintain stable and consistent product quality, the following aspects of equipment management are essential: introduction and development of state-of-the-art machinery and facilities, maintenance and inspection protocols, appropriate layout and positioning of equipment, and allocation of personnel with the expertise to operate these systems effectively.

Material (Raw Materials and Components)

Manufacturing products requires procurement of various raw materials, components, and other resources. To ensure stable manufacturing and effective quality management, organizations must implement comprehensive material management including the following: control of procurement quantities to prevent opportunity losses and excess inventory, management of procurement methods including supplier selection, distribution channels, and purchase pricing, and inspection of materials to verify the absence of defects or shortages.

Method (Manufacturing Processes and Procedures)

Method refers to the processes and procedures used to manufacture products. In quality management systems, standardization of each manufacturing step—establishing clearly defined procedures and methods—is essential. This requires the creation of standard operating manuals and periodic review and update of these documents.

The 5M+E Framework

In addition to the 4M framework, organizations frequently incorporate two additional elements: Measurement (計測) and Environment (環境), creating the 5M+E framework. The total quality variation across all these elements collectively determines the final product quality. Measurement encompasses precision management of measuring instruments and standardization of measurement methods, while Environment includes manufacturing environmental parameters such as temperature, humidity, and cleanliness levels.

The 4M Change Management Concept

General Industrial Definition

In general manufacturing industries, 4M change management is defined as follows: “Man” refers to operator staffing changes, “Machine” refers to changes to manufacturing equipment and tooling, “Material” refers to changes to raw materials and components, and “Method” refers to changes to work procedures, process steps, and measurement methods.

4M Changes in Medical Device Regulation

In medical device regulation, however, the critical elements for design changes (process changes) are Machine, Material, Method, and Measurement—notably excluding Man. This distinction reflects the regulatory reality that design changes in medical devices directly impact the quality of finished products and the safety of patients and users. Therefore, all changes must be implemented with strict rigor and meticulously documented. Furthermore, medical device regulations prohibit any deviation from user requirements, regulatory requirements, or applicable international standards.

In general medical device design contexts, Man is not considered a target for change management. This reflects the regulatory principle that when processes are properly designed and validated, changes in individual operators should not impact product quality or safety.

The Exception: Critical Process Operations

However, in critical process operations—defined as processes involving destructive testing where only sampling inspection can be performed, such as soldering, sterilization, crimping, adhesive bonding, welding, and staking—the management of Man becomes critically important. Critical process operations require pre-validation of the process according to international standards and regulatory guidance, and this process validation must be performed by qualified individuals with appropriate training and experience. The reason is straightforward: if the operator performing process validation differs from the operator who will perform manufacturing, equivalent results may not be achieved in subsequent production runs. Therefore, ensuring the competency and continuity of qualified operators becomes a critical element of change management in these specialized processes.