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Optometry and Vision Science Research Guide: Asking and answering clinical questions

Research resources and information for vision science.
  Evidence-based research and practice / Asking and answering clinical questions

Recommended Reading

The 49 Clinical Questions series: Experts and practitioners ask a series of structured questions based on clinical scenarios. 

Answering clinical questions with evidence


Clinical questions can fall into two categories; (1) background questions, and (2) foreground questions. To examine how these questions can arise, let's consider the following patient encounter:

Clinical Scenario  
Smiling child wearing glasses and an eyepatch

A 4-year-old patient with amblyopia is in your office with his Dad. 

Treatment plan: corrective lenses and schedule a follow-up at which point you may prescribe an eyepatch. 

You now have some additional questions that you would like answered by the evidence, prior to the follow-up appointment. These clinical questions are background and foreground questions. 

Background questions help us improve our understanding of a topic. These types of questions ask for general knowledge about a condition or a thing. 


  1. Does amblyopia present different in pediatric patients?
  2. After successful treatment, can amblyopia reoccur? What is the likelihood of this happening? 

Foreground questions "ask for specific knowledge to inform clinical decisions or actions."2

These questions are usually more complex as they contain several concepts such as a specific population, intervention, comparison and outcome. The organization of these concepts in a clinical questions, is referred to as PICO. For example:

P Population Pediatric patient presenting with amblyopia
I Intervention Eye-patch
C Comparison Glasses
O Outcome Improvement of condition

Example of a PICO-structured foreground question:

Is an eyepatch recommended for the treatment of a child with amblyopia who is already being treated with glasses?


Formulating complex PICO questions takes practice. If you need help, please contact the Optometry and Vision Science Librarian

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