EPIDEMIOLOGIC INVESTIGATION

1. Method of organising data

1.1. Ordering data

1.1.1. Tallies

1.1.2. Stem and leaf displays

1.2. Grouping data

1.2.1. Frequency distributions

1.2.1.1. Frequency

1.2.1.2. Cumulative frequency

1.2.1.3. Relative frequency

1.2.1.4. Cumulative relative frequency

1.3. Summarising data

1.3.1. Measures of central tendency

1.3.1.1. Mean, median, mode, percentiles, quartiles

1.3.1.1.1. Common percentiles are 25th, 50th, 75th

1.3.2. Measures of dispersion

1.3.2.1. Range, variance, standard deviation(s)

1.3.3. Box and whiskers plots

1.4. Displaying data

1.4.1. Tables

1.4.2. Histograms, bar diagrams

1.4.3. Pie charts

1.4.4. Scatterplots

1.4.5. Graphs

2. Data and variables

2.1. Variable

2.1.1. Quantitative

2.1.1.1. Counts

2.1.1.2. Interval

2.1.1.3. Ratio

2.1.2. Qualitative

2.1.2.1. Nominal

2.1.2.2. Ordinal

2.2. Random variable

2.2.1. Discrete

2.2.2. Continuous