A5.2 Explain the use of quantitative methods in analysing loss data

Question 1

What are the definitions of incidence and prevalence?

Answer 1

Incidence - reflects the number of new cases of a particular event in a population over a given time and is often used to describe accidents.

Prevalence - the total number of cases in a particular population as a proportion of the total population. Often used to represent ill health statistics as it includes those who continue to suffer.

Question 2

How does one calculate the ‘accident frequency rate’, the ‘accident incidence rate’, the ‘accident severity rate’ and the ‘ill health prevalence rate’?

Answer 2

ACCIDENT FREQUENCY RATE

• number of work related injuries
  ————————————————- * 100,000
  total number of worker hours worked
• it is a measure of number of accidents per 100,000 hours worked

ACCIDENT INCIDENCE RATE

number of work-related injuries
—————————————————- * 1000
average number of persons employed

-it is a measure of the number of injuries per 1000 employed in a defined period

ACCIDENT SEVERITY RATE

total number of days lost
————————————- * 1,000
total number of worker hours worked

• it a measure of the average number of days lost per 1,000 worked and gives an average number of days lost per accident

ILL HEALTH PREVALENCE RATE

total number of cases of ill health in population
—————————————————————— * 100
number of persons at risk

the calculation gives the percentage of the population with the disease.

Question 3

What are the ways data can be presented?

Answer 3

• Histograms
• Pie charts
• Line graphs