The beginning of the PhD journey, the end, and all that is in between depends to a large extent on your research question. Get it wrong and you are in for three or more years of pain.  Get it right, and the journey becomes immeasurably easier.  So how do you choose a suitable research question?

Firstly, the research question has to lead to a doable PhD. For example, take the following research question: “Does taking once daily probiotics protect against Parkinson’s Disease?” There is nothing wrong per se with the question itself, assuming it is biologically plausible.  It is a perfectly valid and laudable research question.  It is just that Parkinson’s might take 40 years to develop after exposure -  clearly not a feasible time frame for a PhD.  Here is another example: “Do women with only one breast after mastectomy have greater trouble breastfeeding than women with both breasts intact?” Since breast cancer is more often than not a disease of older age, you would have a great deal of trouble recruiting enough younger women with a mastectomy still breastfeeding.

Secondly, the research question cannot be too broad. For example, “Why are men reluctant to express their emotions?” Another perfectly valid research question, but you are likely to have grey hair and your supervisors retired before you complete your PhD!

Thirdly, your research question should not be too tight or closed. For example, “What is the prevalence of refugees from Yemen in South Australia?” – not nearly enough there for a PhD.

Finally, your research question has to generate something new - you cannot simply replicate what someone else has done; unless you can demonstrate that their work was flawed.

Where do you find a good research question? If you come from a clinical background, then you are in a good position to know what the major clinical problems are, and which aspects of your clinical practice lack evidence (usually most of it!). If you are from a non-clinical discipline, then have a look at recent editions of publications in your field. Most published studies end up with a conclusion something like “Clearly, more research is required in this area.” If you are joining a research centre with grant funding, then your research question might be given to you as part of the grant. Finally, a good supervisor should be able to sit down with you and help you develop your question.