Title: SAMPLE SIZE DETERMINATION AND SAMPLING TECHNIQUE

Presenter: Nurse Mary Oluwabukumi Abiona

Date: 7th May 2022

Time: 10am

Venue: Zoom

Moderator: Nurse Ruth Atoki

Introduction

Nurse Atoki welcomed participants to the meeting and informed the group members to register their presence, while others followed suit as the meeting progressed. She introduced the guest speaker and handed it over to her at 10: 10 am. 

Presentation/Lecture

Overview: Sampling is a technique that selects the representative units of a population that will participate in a study. It is divided into two broad parts: 

I. Sampling in qualitative research: This is also known as non-probability sampling.

II. Sampling in quantitative: This is also known as probability sampling.

Sampling in qualitative research or non-probability sampling includes the following types:

Convenience sampling, Purposive or purposeful sampling, Snowball sampling, Theoretical sampling, Extreme or Deviant sampling, Homogeneous sampling, Opportunistic sampling, and Volunteer sampling.

Quantitative research or probability sampling is divided into:

Simple random sampling

Stratified random sampling 

Cluster sampling

Systematic sampling

She further explained that the criteria for a good sample size include:

I. Level of precision.

II. Level of confidence or risk.

III. The degree of variability in the attributes being measured.

There are different formulae to determine definite sample size. Each formula is used in different instances for different studies. However, she advised that the researcher could contact the data analyst for the appropriate formula if unsure of which formula to use.

– The questions asked after the presentation include:

Question: Is it possible to use more than one sampling technique e.g snowball and extreme/deviants sampling for drug addicts?

Answer: Either of the two sampling methods can be used, but the snowball is advisable, then interview respondents individually

Question: What is the difference between the criterion and purpose sampling method?

Answer: both sampling methods are almost the same because both are based on the researcher having a research goal in mind, but the criterion is more inclusive; there are distinct characteristics the respondents must possess that fit the research study for the goal to be achieved.

Question: What are the differences between quota sampling and stratified sampling methods?

Answer: There is no randomization in quota sampling, but everyone has the chance of being selected in the stratified sampling method. There may be bias in quota sampling while there is no bias in stratified sampling.

Question: Why is the need for using a formula to determine the sample size, if the population of a study group is already known and convenient?

Answer: Total sampling is used when the total population is not large e.g 300, but there is a need for the use of the formula to determine the sample size that represents the total population if the population is large e.g 10,000.

Question: Can the interview be used as an instrument for data collection in quantitative research?

Answer: No, the interview is used mainly for qualitative research. 

However, if the researcher wants to carry out an in-depth study using a mixed method (e.g major qualitative, minor quantitative, and vice versa), the findings from the interview method may be used to corroborate the findings obtained from the quantitative data collection.

– Further Announcements/End of meeting: The guest speaker handed over to the moderator after answering the questions, while the moderator appreciated the participants present, and the meeting ended at 11:37 am. 

Reporting member: Nurse Salako Faith.