Read the summary and the most important questions on Research in Biomedical Science

• 1 Lecture 1 - Recap on IBMS

  This is a preview. There are 13 more flashcards available for chapter 1
  Show more cards here

• What is a confounding variable?

  A variable that is related to the independent variable, and therefore can influence the dependent variable (if you study the effect of heat on agression, a confounding variable would be 'amount of road traffic', because that can increase heat and therefore can cause agression)

• What are the two categories for variables?

  Categorical: no meaningful interpretation of differences
  Quantitative: meaningful interpretation of differences

• What are the two types of categorical variables?

  Nominal: there is no logical order in the category (if there are two options: dichotomous)
  Ordinal: there is a logical order in the category (ranked variable)

• What is an example of research in which you strictly spoken use ordinal variables, but you would treat them as if they are continuous?

  When people in the experiment rank things on a scale that is much higher than the number of categories (rate 4 categories from 1-100) (there has become some kind of meaningful interpretation of differences)

• What are two different types of research designs with regards to the differences between groups?

  - Dependent: the measured thing (for example, level of agression), is measured in all individuals of the group, and by calculating the differences in agression, you get your result (paired measurements)
  - Independent: you choose the abnormal or studied thing (for example, 'above a certain level of measurement'), and you rank them in 'present' or 'absent', and by calculating the number of times 'present' occurs in each group, you get your result (unpaired measurements)

• What are two types of experimental designs?

  • Randomized control design
    
  • Cross-over design

• What is the difference between the population and the sample?

  Population: the group you aim to generalize your conclusions to
  Sample: subset of population, the limited group in which you observe data

• What is the difference between frequency and proportion?

  Frequency: how often a value in a data set occurs
  Proportion: how often a value in a data set occurs in proportion to other values

• What is the interquartile range (IQR)?

  The difference between the values that cut off the bottom 25% (Q1) and the top 25% (Q3)

• What is the difference between a bar chart and a histogram?

  The bar chart displays separate categories (like 'men' and 'women'), and the histogram displays quantitative categories (most often ordinal).