My first response back to you would be "enough" for what? What is the purpose of the research? What is the population of possible respondents? Are you planning to make any inferences from the results? If so, 15 is a very small sample, unless for example, that's the total population. There are ways to compensate for small sample sizes. What are you planning to do with the interview and survey data? The best answer to your question is, it depends.

One bit of advice for you, if you plan to go forward with 5 and 15 respondents, is to criticize yourself thoroughly in any report of the work. Inform your audience of the weaknesses in the research design and the results. Inform them of the limits of any conclusions you take from the findings. The burden is on you to show your audience you know what you're doing.

A sample size of 5 is considered small for a qualitative research study, especially for an elite interview. Elite interviews are typically conducted with a small number of individuals who are considered experts in a particular field or have specialized knowledge about a specific topic. However, a sample size of 5 may not provide sufficient data to support the research question or generate rich and detailed findings. It is recommended to have a larger sample size (10-12) to ensure that the findings are generalizable and can be used to draw broader conclusions. Additionally, it is important to consider the characteristics of the participants and the research question when determining the appropriate sample size.

A lot depends on the availability of your potential participants. In particular, if there are very few of them, then a small sample may be all that is possible.

Another way to think of this is the extent to which your research will add knowledge to your field. So, if there are very few studies on this topic, then even a limited amount of data may be valuable.

Dikshita Deka For a qualitative research project, a sample size of 5 is considered modest, especially if the purpose is to conduct elite interviews. Elite interviews are frequently used to collect detailed information from people with specialized knowledge or skill on the study issue. In this scenario, a sample size of 5 may not be enough to offer a thorough grasp of the study issue.

It is also not suggested to have a sample size of 5 for a qualitative research study when the other research question of the same study has a survey sample with a sample size of 15 targeting different respondents. This is due to the fact that the sample size should be determined by the study methodology and the research questions being answered. To guarantee that the study is sufficiently powered to detect the effects being researched, the sample size should be acceptable for both research objectives.

It is vital to highlight that in qualitative research, the sample size is chosen by data saturation rather than statistical power estimates. The moment at which no new information is received from additional participants is referred to as saturation. If the study question can be answered with the information acquired from these 5 people, a sample size of 5 may be adequate. However, if the study issue is difficult, a higher number of participants may be required to reach saturation.

It depends on the size of the population and what you intend to do with the data. The population may well consist of 5 people.

I'd agree with what my colleagues rightly said above. The sample depends on the study population and the purpose of the research.

If your goal is to talk about the frequency of an action or opinion, then 5 is far too few (as also is 15). However, if you are looking for insights into an issue, then 5 might provide useful information. When pretesting survey questionnaires, I've found that people are likely to repeat what others have said after about 5 interviews. (That's not to say that 5 will give you everything you need.) Whatever the number, I'd strive for diversity among your interviewees in terms of their perspectives and situations in order to maximize the information you collect. As others have said, much depends on the nature of your research question, and be careful to note the limitations of your approach.

Dear Dikshita Deka

As you may know, the aim of increasing the number of participants in a qualitative study is to saturate the incoming data about a specific question. If the answers to a specific question are repeated again and again with no new information, then there is no reason to continue asking that question from the next participant. Then yes, you can have different sample sizes for different questions in a single survey.

However, this is only true if you don't want to test anything after the completion of data gathering and the only aim of the study is to descriptively demonstrate the possible answers to each question. If you want to assess some association between the responses of your interviewees and recommend some future quantitative researches in those directions, it is best to ask all the questions from all of them, despite receiving same old answers.

As a final note, I recommend you to increase your sample size either way, because I don't think that 5 interviews can saturate the information about any question.

Good Luck

Thank you everyone for your kind remarks and suggestions. It definitely helped me reading out different viewpoints. James Riggle Aria Behforouz Bradford Chaney Syed Walli Husnain David L Morgan Voke Efeotor Abdulhameed Ashuja'a Fatemeh Khozaei