How many interviews do I need for qualitative PhD?

R

Hello,
As the title suggests, really. I am currently looking for participants for my study- which is a fairly narrow field. I have sent countless emails etc., and I have managed to secure 21 thus far. I was feeling pleased with this number, though I am aiming for 'saturation'. However, I have just been reading another qualitative study that completed 67. I'm not sure I can achieve this number- so I thought I'd ask for advice.
a. how many are you aiming for?
b. Do you know of any other methods to recruit?

H

The fact its qualitative means its about quality not quantity! How many you need depends on whether you get enough info out of your data to answer your research question, only you (with advice from your supervisors) will be able to decide if the number of interviews you have is enough. I have around 24 interviews, all around an hour long. I'm hoping its enough as my submission is in 4 weeks! Those interviews have resulted in masses of rich data, which alongside my literature review/ theory are able to explain the causal patterns in the programme I am researching. Basically, I feel they answer my research question sufficiently (not completely, as there will always be further questions that arise from the data). The number is less important than how you justify your decision, eg. have you recruited 21 just because its hard getting anymore, or because you feel its enough for what you want to achieve? Try not to compare your research with other peoples, I know its tempting, but it isn't helpful and can make you lose confidence in your own work! Would it be possible to leave yourself time so you can secure more interviews at a later date if you feel your analysis is lacking? As for methods to recruit - that's really difficult to comment on without knowing the context eg. group you are recruiting and what for, and any changes to recruitment methods may need an amendment to your ethical approval. My discipline is health/ social care, so for that area I would recommend engaging with/ advertising in the relevant local groups. Hope some of that helps! Good luck!!

D

Quite a common question. The answer is, it depends on the aim of your research question. My PhD was predominantly qualitative. Like hatemyphd84 says, the sampling rationale should specify your rules of inclusion. For my study, it was really important to speak to people who were actually involved in the processes I am interested in. For example, my PhD was interested in the emerging discourses around marriage equality in social and political contexts. I specifically marked differences in potential sampling groups between grassroots activists and campaign leaders as they held different levels of knowledge in terms of what was happening within the wider movement. Ultimately, I restricted my sample (n=10) to include only those who were closely involved in campaign communications (mind my study was mixed methods). So, it might be helpful to think - why are you talking to your current sample? And, why are there experiences important to your research? Hope this helps!

C

Really useful reply... commenting so I can refer back to it lol. Also like your username xD

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