2.7 Writing RQs: An example

RQs emerge from observations, which leads to asking questions, and the need for evidence to answer that question (Tully 2014).

For example, suppose you notice that many people take echinacea when they get a cold; it is reasonable to ask if there is evidence that echinacea helps with a cold in any way. This may lead to an initial RQ (based on Barrett et al. (2010)):

Is it better to take echinacea when you have a cold?

This RQ is clearly poor, but serves as a starting point.

RQs often start as a basic idea, which can be refined by clarifying the POCI elements. For example, what population could we study? Many options exist:

  • ‘You’ is implied by the question… but this is not a useful or practical population.
  • All Australians.
  • Australians adults with a specific “cold.”

What outcome could be used to to determine echinacea’s effectiveness? Again, many options exist:

  • Average cold duration.
  • Average severity of cold symptoms.
  • Percentage of people who take days off work.

The initial RQ cannot be answered because ‘better’ is ambiguous: better than what? We could decide to compare an outcome across different groups, or connect it to something else. For example, the comparison could be:

  • Between taking echinacea and taking no medication.
  • Between taking echinacea and taking another medication.
  • Between taking different doses of echinacea.

Furthermore, we could decide to intervene or not. Whether we decide to include an intervention or not has implications for how the study is conducted and how the results are interpreted.

If we decided not to intervene, the subjects in the study would decide for themselves how to treat their cold. If we did decide to intervene, various interventions could be used:

  • Imposing how frequently the dose was taken; and/or
  • Imposing what doses of echinacea to take.

After making some decisions about P, O, C and I, consider this revised RQ:

Among Australian teenagers with a common cold, is the duration of cold symptoms shorter for teens taking a daily dose of echinacea compared to teens taking no medication?

The P, O, C and I do not have to be comprehensively described in the RQ; some information could be provided later as operational definitions (e.g., dose).

This RQ is much better, but it is still not correct. The outcome is a numerical summary across subsets of the population, not of individuals. So consider this revised RQ (based on Barrett et al. (2010)):

Among Australian teenagers with a common cold, is the average duration of cold symptoms shorter for teens given a daily dose of echinacea compared to teenagers given no medication?

This is a better RQ.

Think 2.8 (POCI) For this RQ above, identify the Population, Outcome, Comparison or Connection, and the Intervention (if any).
Population: Australian teens with a common cold. Outcome: Average duration of the cold. Comparison: Between teens taking echinacea to those not taking echinacea. Intervention: Probably, since the medications are described as being given to the teenagers.

The following short video may help explain some of these concepts:


Barrett B, Brown R, Rakel D, Mundt M, Bone K, Barlow S, et al. Echinacea for treating the common cold: A randomized trial. Annals of Internal Medicine. 2010;153(12):769–77.
Tully MP. Articulating questions, generating hypotheses, and choosing study designs. The Canadian Journal of Hospital Pharmacy. 2014;67(1):31.