BradfordHill'scriteriaofcausationare:
A. Temporality—cause precedes an effect in time
B. Dose–response relationship
Coherence—does not conflict with the current knowledge about the association of interest
D. Analogy—a phenomenon from one area can be applied to another area
The scientific methods for research include:
A. Identify the importance and possible impact of your research, identify what has been so far demonstrated by other colleagues
B. Define a research question that is meaningful and researchable, develop a hypothesis and provide a rationale for it
C. Define specific aims which are measurable and focused, choose an appropriate research design, analyze the data, draw conclusions
D. Communicate the findings, evaluation of communication impact, transformation through changing policy and practice
A quantitative research:
A. Uses the analysis of numerical data
B. Involves large number of participants representative of the population of interest
C. Aims at using statistics to explain the observations
D. Uses various instruments to collect data (questionnaires, monitors, other tools)
Aqualitativeresearch:
A. Data are in the form of words, pictures, and objects
B. Involves small number of participants
C. Aims at providing a complete and detailed description
D. Researcher serves as data-gathering instrument
In a cross-sectional study,
A. Exposure and outcome are assessed at the same time, it is used to study the prevalence of diseases and risk factors in a population
B. Advantages: relatively quick, easy, and inexpensive, can study multiple exposures and outcomes
C. Disadvantages: temporal sequence and causal association between exposure and outcome cannot be established
D. Examples: Health Survey for England (UK) and National Health and Nutrition Examination Survey (NHANES in the US) are both being conducted as a series of cross-sectional examination
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