Surveys: Number of Responses

Thread Attachment browser
N

Nadeem A.

#1
#1
Number of responses

Hi,

What should be the minimum number of responses to analyze any kind of survey statistically? Somebody told me 25, Is there any formula associated to this number or it is fixed?

Your reply with reference will be highly appreciated?

Regards,
 
12 questions to ask before buying a QMS
Elsmar Forum Sponsor
D

D.Scott

#2
#2
Automotive recommends a minimum of 25 subgroups with at least 100 samples.

Be sure though that the process is stable before taking your sub-sets.

Dave
 
N

Nadeem A.

#3
#3
Thanks Dave for the response. Let me make it clear that I am going to analyze some hypotheses related to the ISO 9001:2000. In order to do that research, a survey sheet has been distributed to 138 companies in Quebec and Ontario. We have got 26 responses so far through mail.

Should I start analyzing the responses as I have already got the minimum number of required responses (n=25)?

I am not a statistics guru so that's why I wanted to ensure from any stats champion.
 
D

D.Scott

#4
#4
Hmmmm, I guess I misunderstood the original question. It would be my experience from my old promotional advertising days that a 19 % response to a survey is fantastic. I would do your analysis of that survey whenever you are ready with little expectation of receiving more responses.

I guess I don't see how a statistical analysis of the answers you receive will be valid unless you are going to simply use the % per responses. Statistical analysis as I am used to it in automotive processes just doesn't appear to fit. Unless of course I am missing something - which happens quite often.

Dave
 
Darius

Darius

Quite Involved in Discussions
#5
#5
Nadeem

I don't know for the Automotive industry but as far as I know there is not a constant for the number of responses

The two factors that determine the sample size of a survey are:

* the confidence level
* the precision (or reliability) range.

I added a Handbook, read page 24-28 of the original document could be of any help.

darius.
 

Attachments

G

Graeme

#6
#6
There are methods to analyze small samples (number of responses) from different kinds of surveys. After all, that is what the large polling organizations (Gallup, Harris, Nielsen & etc.) do for a living. The drawback of having a small sample size is that your confidence interval (uncertainty) is larger than what is normally seen in an industrial environment.

The only applicable reference I have on my desk right now is Handbook of Statistical Methods for Engineers and Scientists (Harrison M. Wadsworth, 1990.) In particular, see chapter 9, "Survey Sampling Methods."

Other useful references for the type of methods you need would be those that deal with statistical analyses in medical research or the social sciences, or other fields where small samples are the norm. In an ISO 9000 context, there are several publications on measuring customer satisfaction that may have useful methods.
 
N

Nadeem A.

#7
#7
Thankyou very much to all of you for comments and help. I will search the attachment file and the Hand book of Statitistical Analysis for Scientist and Engineers to initiate my work in the right direction.

Also, I am going for the next step of calling companies to send us back the survey sheet. That will help in increasing the responses bit more.

Thanks Dave for your help in the analysis. I am working on it and will share on this forum.
 
You must log in or register to reply here.
Thread starter Similar threads Forum Replies Date
R Supplier/Vendor Surveys (360) Supplier Quality Assurance and other Supplier Issues 1
G How to assess Customer Satisfaction without using surveys ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 14
S Paperless Temperature Recorder for Temperature Surveys on Heat Treatment Ovens General Measurement Device and Calibration Topics 6
G Simplifying Supplier Surveys and the time they take to be completed Supplier Quality Assurance and other Supplier Issues 15
C Commercial Grade Supplier Surveys - Not qualifed 10CFR50 Appendix B or NQA-1 Other ISO and International Standards and European Regulations 2
B Can we stop Customer Surveys as they are generating low return rates ? Customer Complaints 16
W Customer Satisfaction Surveys in Oil Industry Customer Complaints 8
Crusader Inter-Departmental Customer Service Surveys Quality Tools, Improvement and Analysis 1
M Customer Satisfaction Surveys - User Friendly & Online methods. ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 2
S Customer Satisfaction Surveys - Response Rate, Analysis, Customer Feedback ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 14
S Supplier Quality Survey - Why are those surveys still sent out? Supplier Quality Assurance and other Supplier Issues 13
P Survey's without Response Rate - Surveys distributed by discussion forums Misc. Quality Assurance and Business Systems Related Topics 8
A Company Safety Culture Assessment - How should I structure the Surveys & Interviews? Human Factors and Ergonomics in Engineering 7
D Other ways to Measure Customer Perception apart from Surveys ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 12
J Pyrometry Field Test Instrument to perform TUS (Temperature Uniformity Surveys) AS9100, IAQG, NADCAP and Aerospace related Standards and Requirements 11
K Are Surveys and Interviews considered Objective Measurements? Internal Auditing 25
A Marketing Survey Analysis of Customer Surveys using Minitab Using Minitab Software 1
L Surveys for post-market clinical follow-up EU Medical Device Regulations 1
QMMike Surveys - Customer, Supplier, Custom... ect.... Quality Tools, Improvement and Analysis 1
T How to monitor customer satisfaction without surveys? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 16
D Suppliers and all applicable standards - Supplier Surveys Supplier Quality Assurance and other Supplier Issues 8
W Quantitative Customer Satisfaction Surveys - Templates or Forms? Benchmarking 4
N How to evaluate and analyze Customer Satisfaction Surveys Quality Tools, Improvement and Analysis 16
N Customer Satisfaction Surveys in Seaside Resorts - Servqual? Service Industry Specific Topics 3
R Surveys about Quality Management and Lean Manufacturing The Reading Room 0
M Analysis of Customer Surveys - Auditor not satisfied IATF 16949 - Automotive Quality Systems Standard 10
P Supplier Assessment Surveys - Where I can see some good examples? Supplier Quality Assurance and other Supplier Issues 9
M Grandfathering suppliers to approved supplier list - Have to send out surveys? Supplier Quality Assurance and other Supplier Issues 11
Q Customer Satisfaction Surveys - Are they required by TS16949? IATF 16949 - Automotive Quality Systems Standard 14
A Looking for Customer satisfaction surveys for PDR and CDR. Document Control Systems, Procedures, Forms and Templates 3
L Retention of vendor surveys - Surveys to our company, sent by our vendors Records and Data - Quality, Legal and Other Evidence 5
sardonyx How do you control your clinical documents, like surveys, consents, authorizations? ISO 13485:2016 - Medical Device Quality Management Systems 18
Marc Customer Satisfaction Surveys - A brief .ppt Powerpoint file General Information Resources 0
R Customer Satisfaction - No Surveys or Phone Questions - System implementation ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 17
Marc Customer Surveys - Validity? Fraud? Are they really of any value? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 5
M Customer Satisfaction: We're Doing Surveys - What Else Should We Do? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 2
Sean Kelley How to measure customer satisfaction? Sending out surveys by email? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 21
D customer surveys ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 5
D Supplier Surveys - A controlled document? I say it's a Record Supplier Quality Assurance and other Supplier Issues 19
D Customer Surveys and Feedback - Company ScoreCard Report Misc. Quality Assurance and Business Systems Related Topics 9
V Customer Survey Software - Software or a web host to perform customer surveys Quality Assurance and Compliance Software Tools and Solutions 2
T ISO 9001 + HACCP implementation - Statistics and/or surveys on Combined Registrations Food Safety - ISO 22000, HACCP (21 CFR 120) 15
A Employee and Customer Satisfaction Surveys ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 8
L Customer Satisfaction Surveys - Examples Attached ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 52
K Why 'FD&C act section number' and 'section number' in the title of the act are different? US Food and Drug Administration (FDA) 1
A Risk Number for each software requirement IEC 62304 - Medical Device Software Life Cycle Processes 7
K Adding the Notified Body Number CE Marking (Conformité Européene) / CB Scheme 2
C Quantifying risk in choosing the number of parts, operators and replicates in a GR&R Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 4
Jane's Like-for-like critical raw material change qualification - type of testing/ number of lots required ISO 13485:2016 - Medical Device Quality Management Systems 4
Q LOT or Serial Number Symbol not used when the information is contained in the UDI? 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 1

Similar threads

Top Bottom