Statistical Procedures for the Medical Device Industry

$295.00$325.00

 

This book provides statistical procedures designed to ensure that all statistical regulatory requirements for medical devices are met.  This includes the following applications:

  • Statistical Policy
  • Process Validation
  • Design Verification
  • Component/Material Qualifications
  • Design Validation
  • Audits and Effectiveness Checks
  • Test Method Validation
  • Manufacturing Acceptance Sampling Plans and Inspections
  • Trending Data
  • Setting Specifications

The book is intended for a single user.  While it can be loaned to someone, it should not be given to multiple individuals at the same time.  The pdf includes the name and email of the owner on each page.

Company Licenses to the procedures are also available.

Description

ISBN 978-0-9635122-9-1,  8.5 x 11, 592 pages
By: Dr. Wayne A. Taylor

Provides statistical procedures designed to ensure that all statistical regulatory requirements for medical devices are met. These regulatory requirements can be found in:

  • Code of Federal Regulation 21CFR, Part 820 Quality System Regulations
  • ISO 13485:2016, Medical devices – Quality management systems – Requirements for regulatory purposes

This book is designed for engineers and scientists in the medical device industry.  However, it is also useful for any engineer or scientists involved in product design, process development or manufacturing.

Aids and References:

Tables: The procedures include extensive tables of sampling plans for both validation and manufacturing.

Spreadsheets:  On the spreadsheet tab.

Technical Briefs: While the procedures provide rationales and justifications supporting the recommended approaches.  They also reference the following technical briefs:

Books:  Further details about the statistical techniques covered by the procedures are available in the following books:

CoursesTraining on all the procedures is available.

List of Procedures

Policy and General: STAT-01 is the general policy procedure and STAT-02 provides definitions used by the procedures.

STAT-01     Statistical Policy
STAT-02     Glossary of Statistical Terms

Areas of Application: STAT-03 to STAT-11 describe the statistical requirements for each area of application. They may also provide statistical techniques that are specific to that area of application or reference a supporting statistical technique procedure.

STAT-03     Statistical Techniques for Process Validation
STAT-04     Statistical Techniques for Design Verification
STAT-05     Statistical Techniques for Component/Material Qualifications
STAT-06     Statistical Techniques for Design Validation
STAT-07     Statistical Techniques for Audits and Effectiveness Checks
STAT-08     Statistical Techniques for Test Method Validation
STAT-09     Manufacturing Acceptance Sampling Plans and Inspections
STAT-10     Statistical Techniques for Trending Data
STAT-11     Statistical Techniques for Setting Specifications

Supporting Statistical Techniques: STAT-12 to STAT-19 describe specific statistical techniques. They do not specify any additional requirements beyond those in the policy and application procedures.

STAT-12     Verification/Validation Sampling Plans for Proportion Nonconforming
STAT-13     Verification/Validation Sampling Plans for Rate of Nonconformities
STAT-14     Verification/Validation Sampling Plans for Average
STAT-15     Verification/Validation Sampling Plans for Standard Deviation and RSD
STAT-16     Statistical Techniques for Equivalence Testing
STAT-17     Statistical Techniques for Reliability Life Testing
STAT-18     Statistical Techniques for Normality Testing and Transformations
STAT-19     Rounding of Data

Statistical Techniques

This book includes step-by-step instruction for executing the 43 statistical techniques included below.  For many of the procedures validated spreadsheets are provided.  For selecting sampling plans, extensive tables are provided.  Otherwise, instructions are provided for executing the procedure in Minitab, Distribution Analyzer, Change-Point Analyzer, Sampling Plan Analyzer and VarTran® software packages.

Area/Statistical TechniqueWhere to Find
Confidence Intervals – 1 Group
   Upper Confidence Limit for Percent Conforming – Attribute DataSTAT-12, Appendix D
   Upper Confidence Limit for Percent Conforming – Variables DataSTAT-12, Appendix E
   Upper Confidence Limit for Rate of NonconformitiesSTAT-13, Appendix D
   Confidence Limits for the AverageSTAT-14, Appendix A
   Upper Confidence Limit for Standard DeviationsSTAT-15, Appendix I
   Upper Confidence Limit for Relative Standard DeviationsSTAT-15, Appendix J
Confidence Intervals – 2 Groups
   Confidence Limits for the Difference between Two AveragesSTAT-16, Appendix A
   Confidence Limits for the Difference between Two Averages – Paired DataSTAT-16, Appendix C
   Confidence Limits for the Ratio of Two Standard DeviationsSTAT-16, Appendix D
Equivalence Tests
   Equivalence Test for the AverageSTAT-14, Appendix B
   Equivalence Test for Two AveragesSTAT-16, Appendix B
   Equivalence Test for Two Averages – Paired DataSTAT-16, Appendix D
   Equivalence Test for Two Standard DeviationsSTAT-16, Appendix F
General Techniques
   Regression Analysis – Correlation Study for Substitute Measurement MethodsSTAT-08, Appendix I
   Analysis of Variance (ANOVA)STAT-18, Appendix E
   Kruskal-Wallis TestSTAT-18, Appendix F
   Capability StudySTAT-11, Appendix F
   Screening Experiment – Design of ExperimentSTAT-11, Appendix D
   Response Surface Study – Design of ExperimentsSTAT-11, Appendix E
Normality Test
   General Normality Tests (Anderson-Darling, Shapiro-Wilk and Skewness-Kurtosis All)STAT-18, Appendix A
   Skewness-Kurtosis Specific Normality TestSTAT-18, Appendix C
Sampling Plans (Also see Equivalence Tests)
   Attribute Single and Double Sampling Plans for Proportion NonconformingSTAT-07, Appendix A
STAT-09, Appendix A
STAT-12, Appendix A
   Variables Single and Double Sampling Plans for Proportion NonconformingSTAT-09, Appendix A
STAT-12, Appendix B
   Narrow Limit Gauging Single and Double Sampling Plans for Proportion NonconformingSTAT-09, Appendix A
   Single and Double Sampling Plans for Rate of NonconformitiesSTAT-07, Appendix B
STAT-13, Appendix A
   Single and Double Sampling Plans for Standard DeviationsSTAT-15, Appendix A
   Single and Double Sampling Plans for Relative Standard DeviationsSTAT-15, Appendix B
   Product Life Sampling Plans – Parametric with Specified Test TimeSTAT-17, Appendix A
   Product Life Sampling Plans – Censored Failure Time PlansSTAT-17, Appendix B
Specification Setting
   Tolerance AnalysisSTAT-11, Appendix A
   Tolerance Sensitivity AnalysisSTAT-11, Appendix B
   Robust Design using Tolerance AnalysisSTAT-11, Appendix C
Test Method Validations
   Gauge R&R StudySTAT-08, Appendix B
   Gauge Reproducibility Study (Variance Components Analysis)STAT-08, Appendix C
Trending Tools
   Pareto ChartSTAT-10, Appendix A
    or Average-Standard Deviation Control ChartSTAT-10, Appendix B
   Normalized IN Chart for Individual ValuesSTAT-10, Appendix C
   Box-Cox I ChartSTAT-10, Appendix D
   U Chart for Counts with Independent EventsSTAT-10, Appendix E
   P Chart for Pass/Fail Proportions with Independent EventsSTAT-10, Appendix F
   Laney U’ Chart for Counts with Dependent EventsSTAT-10, Appendix G
   Laney P’ Chart for Pass/Fail Proportions with Dependent EventsSTAT-10, Appendix H
   Change-Point AnalysisSTAT-10, Appendix I

Spreadsheets

The spreadsheets below are provided as part of purchasing or licensing the book Statistical Procedures for the Medical Device Industry.  Permission is granted to purchasers of the book to use and modify the spreadsheets for their personal use.  Permission is granted to companies licensing one of the procedures in the title of the Excel file to use and modify the spreadsheet for use within the company per the book’s licensing agreement.

There are two versions of each spreadsheet. The first is protected. Only cells required to enter data and select options can be altered. This is the version used for the validation as this ensures the formulas cannot be changed. However, tabs can be deleted and copied to customize the layout of the spreadsheet.  The second version is unprotected. This allows access to the formulas and allows the spreadsheets to be customized.

The protected versions have been validated as required in the medical device industry. The validation package can also be downloaded below.

STAT-10 – Control Charts.xlsx

STAT-10 Excel

Download STAT-10 - Control Charts - Protected

Download STAT-10 - Control Charts - Unprotected

Download STAT-10 - Control Charts - Validation Report PDF

STAT-12 to 16 – Confidence Intervals and Equivalence Tests.xlsx

STAT-12 to 16 Excel

Download STAT-12 to 16 - Confidence Intervals and Equivalence Tests - Protected

Download STAT-12 to 16 - Confidence Intervals and Equivalence Tests - Unprotected

Download STAT-12 to 16 - Confidence Intervals and Equivalence Tests - Validation PDF

STAT-18 – Skewness Kurtosis Normality Tests.xlsx

STAT-18 Excel

Download STAT-18 - Skewness Kurtosis Normality Tests - Protected

Download STAT-18 - Skewness Kurtosis Normality Tests - Unprotected

Download STAT-18 - Skewness Kurtosis Normality Tests - Validation Report PDF

Errata

Errata for Second and First Printing

Multiple occurrences of the word gage should be replaced with gauge.

   STAT-02  Glossary of Statistical Terms 

Page 24, under definition for Distribution function, “average of 7” should be “average of 10.”

STAT-03  Statistical Techniques for Process Validation

Pages 35, 38 and 48, “OC characterization” should be “OQ characterization”

STAT-08     Statistical Techniques for Test Method Validation

Page 119, the guardband equations are in error and should read as shown below.

Lower guardband limit = LSL + Maxbias + K x UCLσ-guardband
Upper guardband limit = USL + Minbias – K x UCLσ-guardband

   STAT-12    Verification/Validation Sampling Plans for Proportion Nonconforming

Page 360, for 95/90 Variables—One-Sided Specification the Ppk acceptance criterion for n=15 can be reduced from 0.70 to 0.69.

   STAT-18    Statistical Techniques for Normality Testing and Transformations

Page 570, Section 6.1 should say: “For a single normality test, the test is
considered to pass if the p-value is > 0.05.”

 

Errata for First Printing

 They have been corrected in the current second printing.

   Table of Content and elsewhere

STAT-10 title has “tending” rather than “trending”.

   Introduction

Table 1 of page 3.  RNP should be RPN.

   STAT-02     Glossary

Page 25, kurtosis, as defined here, is sometimes referred to as the excess kurtosis and is the statistical kurtosis minus 3.

   STAT-08     Statistical Techniques for Test Method Validation

Page 101, the reference in Section 6.3.2 to Section 6.3 should be a reference to Section 6.3.1.

   STAT-09    Manufacturing Acceptance Sampling Plans and Inspections

Page 142, Example box should give n=80, a=2 as the “also use” sampling plan rather than n=80, a=3.

Page 162, the AQL=10%, L-3, Variables Single, σ unknown plan is in error.  Change MSD to 333.3%.

Page 173 the AQL=1%, L-8, Variables Single, σ unknown plan is in error.  Change MSD to 22.5%.

   STAT-10     Statistical Techniques for Trending

Page 200, the last sentence should reference Appendix I and not Appendix J.

Page 214 the equations for the control limit should be as shown below.

Control Limit Equation

Page 233 the equations for the control limits of the IN chart should be as shown below.

In Control Limits

Page 247, bottom right, 0.000502 should be 0.000557.

   STAT-13     Verification/Validation Sampling Plans for Rate of Nonconformities

Page 424 makes reference to the Beta distribution.  It should have referenced the Gamma distribution.  There are also some formatting issues.

   STAT-15     Verification/Validation Sampling Plans for Standard Deviation and RSD

Page 471 shows screenshots for 95% confidence rather than the 90% confidence stated in the text.  The confidence statements given in the text are correct but do not align with the graphic.

Page 472 shows formulas for the confidence intervals for the standard deviation.  These formulas use the CHIINV function in Excel, which returns the inverse of the right-tailed chi-squared distribution function.  These are the formulas used in the spreadsheet.  For the more common inverse of the left-tailed chi-squared distribution function, reverse the formulas for the upper and lower confidence limits.

   STAT-17    Statistical Techniques for Reliability Life Testing

Page 530, the last two paragraphs of the example should read:

To select a plan, use Appendix B of STAT-13. The ratio RQL/AQL = 4. The
resulting single sampling plan is n = 11.8424/RQL, a = 6. Plugging 2 in for the RQL
results in n = 5.9212. This can be rounded up to n = 6 years.

It is desired to complete the testing within 6 months. This requires testing 12 pumps
for half a year to produce 6 years of test time. If 6 or fewer service events occur,
the sampling plan passes, and it can be stated with 95% confidence that the rate of
service events is below 2 per year.

Page 531, the same changes should be made to the last two paragraphs of the example.

   STAT-18     Statistical Techniques for Normality Test and Transformations

Page 565 if states Zk is valid for n≥20.  Simulations demonstrate it is valid for n≥15.

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