# Understanding sample size for the success of your research study

In many research studies, there is something called a Sample size. It is a term used to refer to the total number of research participants. These participants represent the target audience. The sample size defines the total number of respondents in your research study.

In research studies, a decent degree of statistics is applied in determining useful mathematical relationships. The sample size is one of such mathematical relationships that is analysed with statistical analysis. The value of sample size will determine the level of accuracy of your research study.

Important determinants for sample size

When calculating the sample size for your research study, certain factors are important. They can be used to add context to the sample size and are used to calculate it. They are:

The margin of error: Also known as a confidence interval, this is a quantity that is used to determine how accurately your sample size can produce an accurate result that truly represents the entire population. A smaller margin of error value indicates exactness and accuracy.

Confidence Level: This is a value used to assess the degree of certainty or probability that the confidence interval would have the true parameter of the general population of multiple samples are randomly taken. It is expressed in percentages. The confidence level increases with larger sample sizes.

Standard Deviation: This is a useful quantity that is used to determine the distribution of a set of data from the mean. In estimating sample sizes, the standard deviation is used to express the degree of variance between individual responses as well as from the mean response. Standard deviation in research sampling is usually the degree of variation among responses.

Population Size: This is the whole group of people or items that your research study is based on. The sample is usually drawn from the population size. It is possible for the total population size of a research study to be known. In other research, the total population size may not be known. In each case, it is important to select a sample size that truly represents the true features of the total population.

Calculating the sample size for research surveys

You can learn how to calculate a sample size for any survey or you could just get a survey provider to do this on your behalf. Also, there are calculators for sample size calculation on most websites from survey providers. You can easily calculate the sample size of any survey if you know the key terms and if you can apply Andrew Fisher’s Formula.

Andrew Fisher’s Formula is applied in the calculation of sample sizes. However, before this is done, there are useful values that have to be obtained. Before calculating your sample size, you need to calculate or obtain, the population size, the confidence level, the margin of error, the standard deviation, and the Z-Score.

The Z-Score is a useful quantity that is derivable by converting the confidence level accurately. You have to know how this is done. The moment you obtain all of these important values, you can now put the values into the Andrew Fisher’s Formula. This will then easily produce your desired sample size.