Measure
Data Collection Plan
Carry CTQC definitions into practical collection methods, sampling plans and ownership.
Control · Interactive CI tool
Control Chart Builder
A control chart plots observations in time order against limits estimated from a chosen baseline. It helps distinguish routine variation from patterns that warrant investigation.
Read freely. Creating a worksheet requires a verified free beta account. No payment or manual beta approval.
When this tool helps
Use it when repeated observations have comparable definitions and a defensible sequence or subgroup structure.
It supports more disciplined responses than treating every rise or fall as a process change.
When to choose another method
Use Pareto for category priorities and Process Capability to compare a sufficiently supported process model with specifications. Control limits are not customer acceptance limits.
How to use it in CI Tools
- Read the guide and agree the question, definitions and required starting information.
- Open a separate blank worksheet or the built-in synthetic practice sample. Follow the tool-specific steps and review its warnings.
- Check the interpretation and save an editable .citools file to your computer. Keep reports as separate exports.
Fictional example snapshot
Packaging defect proportion
A fictional supplier has 20 baseline samples of 100 inspected units each, with defective-unit counts 8, 10, 12, 10 repeated five times. The pooled baseline proportion is 200/2,000 = 10%.
| Sample of 80 | 18 defective units = 22.5%; upper proportion-chart limit is approximately 20.06% |
|---|---|
| Sample of 120 | 12 defective units = 10%; upper limit is approximately 18.22% |
| Completed conclusion | The first sample exceeds its upper limit; the second does not. Investigate the first sample without claiming a specific cause. |
These figures illustrate the method; they are not clinical instructions, universal targets or verified results from a real organization.
Read the complete worked example and its interpretationLearn the method, then put it into practice
The full guide includes prerequisites, interface-specific steps, two fictional examples, common mistakes and interpretation help. It is available without registration.
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