# The Naked Scientists Forum

### Author Topic: How do you calculate the sample size for a survey?  (Read 2393 times)

#### Doni12

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• Posts: 1
##### How do you calculate the sample size for a survey?
« on: 03/04/2008 15:09:17 »
Dear friends,

I am not if this is the right way to go about posting here but I need some assistance. Does anyone here have experience in surveys? I need some guidance. I am designing a nationwide survey on students dietary habits. Let's say the country is divided into 5 parishes with the following number of schools and students:

Parishes----Schools-----School population
A -----------20 ---------8,000
B ------------9 ---------20,000
C -----------40 ---------10,000
D -----------10 ---------20,000
E -----------6 ----------6,000

1. How do I select a reasonable nationwide sample of students from
the entire school population for this study?

2. Parish Based Approach.
Would it be reasonable enough if I randomly select a specific number
of schools (for example 5 schools) from each parish then add up
the number students from these five schools and randomly choose a
determined amount of students for the study? What should be my
sample size?

« Last Edit: 05/04/2008 10:42:27 by chris »

#### DoctorBeaver

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##### Re: How do you calculate the sample size for a survey?
« Reply #1 on: 03/04/2008 21:03:22 »
I don't know if this site will help...

http://www.surveysystem.com/sscalc.htm

Hopefully it will.

Are you doing this survey as part of a course?

#### The Naked Scientists Forum

##### Re: How do you calculate the sample size for a survey?
« Reply #1 on: 03/04/2008 21:03:22 »