Maths - Bar charts
Scientists use graphical and Collection and interpretation of data. methods to analyse patterns of data related to disease.
Drawing bar charts
Data are often displayed in a graph or chart. These might display trends that are not as clear when just looking at data in a table.
Bar charts show data collected for separate groups. The height of the bar is proportional to the measured number or The total number of times an event occurs..
This table of data and bar chart show the number of deaths that could be avoided in England in 2023 from different causes.
| Cause of death | Number of deaths that could be avoided, rate per 100,000 of population |
| Cancer | 74.9 |
| Cardiovascular disease | 66.1 |
| Alcohol and drug-related | 27.3 |
| Infectious diseases | 4.2 |
| Injury | 18.3 |
| Respiratory disease | 30.1 |
| Other | 17 |
| Cause of death | Cancer |
|---|---|
| Number of deaths that could be avoided, rate per 100,000 of population | 74.9 |
| Cause of death | Cardiovascular disease |
|---|---|
| Number of deaths that could be avoided, rate per 100,000 of population | 66.1 |
| Cause of death | Alcohol and drug-related |
|---|---|
| Number of deaths that could be avoided, rate per 100,000 of population | 27.3 |
| Cause of death | Infectious diseases |
|---|---|
| Number of deaths that could be avoided, rate per 100,000 of population | 4.2 |
| Cause of death | Injury |
|---|---|
| Number of deaths that could be avoided, rate per 100,000 of population | 18.3 |
| Cause of death | Respiratory disease |
|---|---|
| Number of deaths that could be avoided, rate per 100,000 of population | 30.1 |
| Cause of death | Other |
|---|---|
| Number of deaths that could be avoided, rate per 100,000 of population | 17 |
Question
Use the information in the bar chart to find out the number of deaths that could be avoided resulting from causes other than those in the table.
Seventeen per 100 000 of population.
Note that bar charts are sometimes displayed horizontally.
Histograms
A graphical representation of the distribution of numerical data. look similar to bar charts, but show how frequently data occur within certain ranges.
The The variable that is changed, to investigate its effect on the dependent variable in an experiment. is therefore continuous and is divided into sub-sections or classes.
This histogram shows data from a Scottish study of the proportion of people of different ages with depression who consult their doctor. The independent variable here is age, but the histogram shows different groups within the variable of range allowing the data to be visually comparable.