HC1: Research questions

Medical research

The ultimate goal of medical research is to improve medical practice. There are different aspects of medical practice which form 4 classes of medical research:

• Etiology (prevention/risk factors of a medical disease)
  • Is a high caloric diet a risk factor for cardiovascular disease?
• Diagnosis
  • What is the probability of having a hip fracture if the affected leg is shorter and in exorotation?
• Treatment
  • Does chloroquine treatment reduce the risk of mortality among COVID-19 patients admitted to the ICU?
• Prognosis
  • What is the probability of dying within 5 years after breast cancer diagnosis?

Research questions

Research questions arise in practice. It is important to particularly articulate a research question → they are the starting point when designing a study or when reading a paper. A research question should be answerable and have standard elements/components.

Components:

Research questions can consist of several types of standard components:

• PICO: most often used
  • Patient (population)
  • Intervention
  • Comparator
  • Outcome
• DDO
  • Domain
  • Determinant
  • Outcome

Examples:

Examples of research questions are:

• To what extent does alemtuzumab compared to interferon-β improve the time until relapse occurs in patients with relapsing remitting MS?
  • Classification: treatment
  • Patients: patients with relapsing remitting MS
  • Intervention: alemtuzumab
  • Comparator: interferon-β
  • Outcome: time until relapse occurs
• What is the predictive value of a second ultrasound, in case a first ultrasound was inconclusive, in patients suspected of having an acute appendicitis?
  • Classification: diagnosis
  • Patients: patients suspected of having an acute appendicitis, in whom a first ultrasound was inconclusive
  • Intervention: second ultrasound
  • Comparator: /
  • Outcome: appendicitis
• Is smoking a risk factor for lung cancer?
  • Classification: etiology
  • Patients: humans
  • Intervention: smoking
  • Comparator: no smoking
  • Outcome: lung cancer