Evaluating Data on Lung Disease\

Question 1

A risk factor is any

Answer 1

factor that correlates with (is linked to) an increased chance of suffering from a particular condition or disease
Example of risk factors for the incidence of lung disease is exposure to smoking and pollution

Question 2

The incidence of disease describes the

Answer 2

number of cases of a disease that occur in within a particular group of people within a given time

Question 3

Prospective studies involve collecting data

and its advantages and disadvantages

Answer 3

as it becomes available

It can be beneficial in that more accurate data can be obtained

It can be highly time-consuming

Question 4

Retrospective studies involve collecting data from the

Answer 4

past
The data collected may be unreliable as people forget details or alter them
Results can be obtained more rapidly

Question 5

Collecting data for studies from the population can be very difficult for a number of reasons
Controlled experiments where only one variable is investigated can’t be carried out on humans due to ethical implications. For example, it would be immoral to ask a random group of people to smoke exactly 10 cigarettes every day for 10 years, while the control group is banned from smoking
Finding people with sufficiently similar lifestyles can be difficult
Long term studies with multiple follow-ups take a lot of time and money
It is important to remember that those that make one healthy life choices that is being monitored (e.g. don’t smoke) may be more likely to live generally healthier lives (e.g. regularly exercise) which also may have an effect on their risk of disease compared to others that chose other lifestyles

Question 6

Sample size:

Answer 6

the number of people involved in the study is very important. A study with a large sample size will have more reliable results

Question 7

Individuals in the sample: if the study only has women aged 20-40 this data is not able to suggest the effect on a male or an older woman, it is therefore important to state the who the data is referring to when

Answer 7

when evaluating it

Question 8

Levels of exposure: make sure to pay attention to the different levels of

Answer 8

exposure to the risk factor that has been included in the study. Eg. 10 cigarettes a day, 20 cigarettes a day, no cigarettes and for how long

Question 9

Control group: identify if the control group matches the other groups closely enough. The people in the control group should be

Answer 9

be of a similar age and background to those in the other groups

Question 10

Statistical significance: try to determine if the differences between groups are

Answer 10

sufficiently large and whether any statistical tests have been carried out to test the significance of the results

Question 11

The influence of other factors/variables: bear in mind that there are many variables that have not been controlled due to moral reason. This means there may be a combination of factors that are interacting with each other to influence the results:

Answer 11

Genetics
Secondary exposure to smoking
Other factors that have not been controlled that has an effect on lung health (e.g. exercise

Question 12

Calculating the Relative Risk
If the incidence or mortality rate of the disease for different groups has been provided, it can be helpful to calculate the relative risk of each group for comparison
For example, the percentage chance of a person

Question 13

Remember that some diseases developed slowly so there may be a delay between exposure to a risk factor and the disease becoming visible in the population