QUESTIONS TO ASK IN PROGNOSTIC STUDIES

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QUESTIONS TO ASK IN PROGNOSTIC STUDIES

• Onofre Morán MD, MSc.
• Professor, Faculty of Medicine, Universidad
  Autónoma de San Luis Potosí, S.L.P. México.
• PhD Candidate
• University of British Columbia, Vancouver, Canada.

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Questions to ask in Prognostic studies

• WHY
• Justified?
• Hypothesis/purpose of the study?
• HOW
• Was an inception cohort assembled?
• Were objective outcome criteria used?
• Was the outcome assessment blind?
• Were DIAGNOSTIC SUSPICION BIAS and EXPECTATION
  BIAS avoided?

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Questions to ask in Prognostic studies

• WHO
• Is the studied sample CLEARLY described?
• Is the referral pattern described?
• Is there evidence of REFERRAL FILTER BIAS or
  DIAGNOSTIC ACCESS BIAS?
• Do the authors account for every patient who was
  eligible for the study but did NOT enter it?
• Was complete follow-up achieved?

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Questions to ask in Prognostic studies

• WHAT
• Was adjustment for known prognostic factors
  carried out (THERAPEUTIC ACCESS BIAS)?
• Was there LEAD TIME BIAS considered?
• Were losses to follow-up handled appropriately
  and was their clinical status determined?
• Were all clinically relevant outcomes reported?

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Questions to ask in Prognostic studies

• HOW MANY?
• Was statistical significance considered?
• Were statistical test applied appropriately?
• Was any measurement of risk provided?
• Was the study large enough to detect important
  outcomes?
• If no increased risk was found, was there any
  consideration of the power of the study?

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Questions to ask in Prognostic studies

• SO WHAT?
• Are the results clinically significant?
• Are the results (and patients) sufficiently
  described to be generalized to the clinical
  practice?
• Is the therapeutic intervention feasible in your
  practice?