**DEPARTMENT OF VETERANS BENEFITS MANUAL**

**QUALITY CONTROL**

WASHINGTON, D.C. 20420 AUGUST 22, 1966

M20-2 Department of Veterans Benefits

> Veterans Administration
>
> Washington, D.C. 204
>
> August 22, 1966

Department of Veterans Benefits Manual M20-2, \"Quality Control,\" is
published for compliance by all concerned.

When applicable, the instructions and procedures in this manual will be
referenced in other department administrative issues containing program
quality control and evaluation instructions.

> A.W. .STRATTON
>
> Chief Benefits Director

Distribution: RPC 2124 assigned

FD

August 22, 1966 M20-2

INTRODUCTION

This is a working manual. It provides basic department instructions and
procedures to be used in the development and maintenance of program and
field station quality control activities. It includes basic sampling
procedures which must be followed whenever samples are used to estimate
a quality level, make quality comparisons, or to determine compliance
with standards.

Quality control has assumed various forms in the past, but has always
had quality improvement as the primary objective. The Department of
Veterans Benefits previously introduced the use of statistical quality
control techniques, because it would provide, at minimum cost, the
information needed for quality improvement. Most quality control actions
and related decisions are based largely on information obtained from
samples. The cost of continuous 100 percent inspection of all work done
would be prohibitive. Sampling has the obvious advantage of economy and
speed. Since making inferences from samples is a basic function of
statistics, in this sense every quality control plan involving sampling
is statistical quality control.

This manual explains statistical quality control techniques in
sufficient detail for care­ful observance of sound sampling procedures
and other basic statistical principles. Just enough theory is included
to provide working rules for the application of the more commonly used
techniques and for recognizing also the limitations of such techniques.
It presents the management point of view toward quality control as well
as basic operating rules. In addi­tion, this manual may be used in the
following ways:

> 1\. As a guide for improving program and field station quality control
> methods.
>
> 2\. As a reference for operating personnel in conducting quality
> control activities.

3\. As a guide for estimating and evaluating quality levels to identify
improvement needs.

> 4\. As a text for use in conducting supervisory training sessions in
> quality control.

M20-2 August 22, 1966\
RESCISSIONS

1\. Interim Issue\
/Section V and appendix A, EM 28-2

2\. DVB Circular

> 20-64-17

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August 22, 1966 M20-2

CONTENTS

PARAGRAPH PAGE

CHAPTER 1. GENERAL QUALITY CONTROL INSTRUCTIONS

1.01
Quality - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
1-1

1.02 Quality,
Control - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
1-1

1.03 Objectives of Quality Control in
DVB - - - - - - - - - - - - - - - - - - 1-1

1.04 Byproducts of Effective Quality
Control - - - - - - - - - - - - - - - - - 1-1

1.05 Quality Control
Methods - - - - - - - - - - - - - - - - - - - - - - - - - - - 1-2

1.06
Responsibilities - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
1-2

1.07 Organizing for Quality
Control - - - - - - - - - - - - - - - - - - - - - - - 1-3

1.08 Quality Control
Principles - - - - - - - - - - - - - - - - - - - - - - - - - 1-4

1.09 Error or Quality
Defect - - - - - - - - - - - - - - - - - - - - - - - - - - - 1-5

1.10 Sampling
Procedures - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1-5

1.11 Feedback\--Key to Quality Planning and
Control - - - - - - - - - - - 1-7

1.12 Timeliness of
Operations - - - - - - - - - - - - - - - - - - - - - - - - - - 1-7

1.13 Complaints\--Significant Quality
Indicator - - - - - - - - - - - - - - - 1-7

> CHAPTER 2. STATISTICAL QUALITY CONTROL

2.01 SQC
Applications - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
2-1

2.02 Quality
Mindedness - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2-1

2.03 Functions of
SQC - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2-1

2.04 Cost of
Quality\--SQC - - - - - - - - - - - - - - - - - - - - - - - - - - - -
2-1

2.05 Developing an SQC
Plan - - - - - - - - - - - - - - - - - - - - - - - - - - - 2-2

2.06 SQC Measurements and
Standards - - - - - - - - - - - - - - - - - - - 2-3

2.07 Timeliness Measures and
Standards - - - - - - - - - - - - - - - - - - 2-3

2.08 Quality
Level - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
2-4

2.09 Revising Acceptable Quality Level or
Standard - - - - - - - - - - - - - - 2-4

CHAPTER 3. SAMPLING VARIATION IN QUALITY CONTROL

3.01 Recognition of Sampling
Variation - - - - - - - - - - - - - - - - - - - - - 3-1

3.02 Error Distribution\--Small Finite
Population - - - - - - - - - - - - - - - - 3-1

3.03 Characteristics of Sample
Combinations - - - - - - - - - - - - - - - - 3-1

3.04 Frequency of Occurrence of Possible Sample Combinations - - - 3-2

3.05 Variability in a Random Sample
Result - - - - - - - - - - - - - - - - 3-2

3.06 Applying Principles of Statistical Sampling to Quality
Control - - - - - - - 3-3

CHAPTER 4. TABLE OF THREE STANDARD DEVIATION CONTROL

LIMITS FOR PERCENT IN ERROR

4.01 Purpose of the
Table - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4-1

4.02 Control Limits Used in the
Table - - - - - - - - - - - - - - - - - - - - - - 4-1

4.03 What the Table
Shows - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4-1

4.04 Assumptions in Using the Table to Interpret Sample
Results - - - - - 4-2

4.05 Determining Whether a Process is in Statistical
Control - - - - - - - - 4-2

4.06 Determining Sampling
Error - - - - - - - - - - - - - - - - - - - - - - - 4-3

4.07 Determining Sample
Size - - - - - - - - - - - - - - - - - - - - - - - - - - 4-4

4.08 How to Use the Table When Quality Level (Percent in Error)

> Exceeds
> 500% - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
> 4-5

4.09 Use of Independent Samples and Table to Verify Reported Quality

> Levels - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
> 4-5

4.10 Review of Cases or Work Units Previously Quality Checked by the

Supervisor - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
4-7

4.11 Determining Compliance With Standards of
Timeliness - - - - - - - - - - 4-7

4.12 Mathematical Formulas Used to Develop the Table of Three Standard

> Deviation Control
> Limits - - - - - - - - - - - - - - - - - - - - - - - - - 4-10

M20-2 August 22, 1966

CONTENTS\--Continued

PARAGRAPH PAGE

> CHAPTER 5. SQC CHART FOR PERCENT IN ERROR

5.01 Management Value of SQC
Charts - - - - - - - - - - - - - - - - - - - - - - 5-1

5.02 SQC Chart Influence on Quality Improvement - - - - - - - - - - - -
5-1

5.03 SQC Chart
Design - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 5-1

5.04 Control Chart
Evidence - - - - - - - - - - - - - - - - - - - - - - - - - - - 5-2

5.05 SQC Chart Evidence of a Quality Level Better Than the Standard -
5-6

5.06 Tendency to Ignore Favorable SQC Chart Evidence - - - - - - - - - -
5-7

**APPENDIXES**

APPENDIX

> A Glossary of Terms - - App. A-1\
> B SQC Chart Illustration App. B- I\
> C Table of Random Sampling Numbers App. C-1\
> D Minimum Acceptable Sample Percentages for Specified Percentages
>
> of Work Units
> Processed - - - - - - - - - - - - - - - - - - - - - - - - - App. D- I\
> E Table of Three Standard Deviation Control Limits for Percent in
> Error App. E- I

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