One of the core concepts of evidence-based clinical practice (EBCP) is the development of a PICO question. You may have heard this term bandied about in discussion but may not have been exactly what is meant by it. Let me discuss that here.
One of the initial steps in applying the concepts of EBCP to clinical practice is formulate a clinical question. This is important for several reasons, one of the most important being that it helps you design an appropriate search strategy for locating information; that is, you need it to get a useful answer to the clinical question you are attempting to answer. This would occur, for example, if you were confronted with a patient for whom you are not sure how to proceed, not for one where you know exactly what you wish to do. Developing a PICO question is quite helpful in this regard.
PICO standards for: Patient (or Population or Problem), Intervention, Comparison (or Comparator) and Outcome.
P: Patient. What kind of patient is the focus of your question? That is, what is his or her diagnosis, population of problem? Typically, we are looking at a diagnostic question; we have a pteitn with a particular diagnosis that lies outside our area of general knowledge and we are trying to figure out what to do. The more carefully we can define this patient, the better we can search for information. Therefore, we need to look at not just the diagnosis, but perhaps at age range, gender, stage of illness, severity of illness, etc.
I: Intervention. What intervention are we considering using for this patient? In the case of chiropractic, it might include chiropractic adjustment, or perhaps it might involve some other supportive therapy such as physiotherapy of some sort, massage, mobilization or exercise. We could do the same if we were examining a new diagnostic test, to compare it against an established test.
C: Comparison. What do you wish to compare the intervention with? That is, what is the control you are looking at for your intervention? Normally, the comparison should be some established standard treatment for the condition of interest. At times, it might no treatment at all. For manipulation/adjustment, perhaps it would be an intervention for pain relief, such as NSAIDs, or perhaps some other form of conservative care such as exercise. It could even be surgical.
O: Outcome. What, ultimately, is the outcome you are interest in? Often in chiropractic it will be pain relief or reduction of disability, but it is certainly not limited to this. You could do the same approach for reduction of subluxation, remembering that you would compare your method of reduction measurement to some other measurement of same. You could look at sot issues, if you wanted.
Once you have the PICO question developed, it will help inform the search strategy you develop to locate information you can then assess and apply to your patient. The next step in the process of finding and applying evidence would be to conduct a literature search.