Chapter 21 - Mortality and morbidity

Question 1

Explain why it is necessary to have different mortality tables for different classes of lives

Answer 1

When a life table is constructed it is assumed to reflect the mortality experience of a HOMOGENEOUS group of lives. In other words, all the lives to whom the table applies follow the same stochastic model of mortality represented by the rates in the table. This means that the table can be used to model the mortality experience of a homogeneous group of lives that is expected to have a similar experience.

If the table is constructed for a heterogeneous group, then the mortality experience will be depend on the exact mixture of the lives in that group. Such a table could only be used to model mortality in a group of lives with the same population structure as the group used to produce the table. Hence the table will have very restricted uses.

Question 2

List factors that directly affect mortality and morbidity rates

Answer 2

PHONECARD HM GG

• POLITICAL unrest
• HOUSING status
• OCCUPATION
• NUTRITION
• EDUCATION
• CLIMATE / geography
• AGE
• RELIGIOUS attributes
• DANGEROUS activities
• HIV status
• MARITAL status
• GENETICS
• GENDER

Question 3

List the main forms of selection

Answer 3

TASTiC

• Temporary initial selection
• Adverse selection
• Spurious selection
• Time selection
• Class selection

Question 4

Temporary initial selection

Answer 4

It is usually the case that mortality / morbidity rates depend on the duration since some event, up to some duration s. After duration s they are independent of duration.

This phenomenon is called temporary initial selection, and s is called the length of the select period.

Question 5

Class selection

Answer 5

Class selection occurs where each group is categorized by the nature of a particular characteristic of the population.

Examples include:
- gender
- occupation
- age

Question 6

Time selection

Answer 6

Where a select group is taken from a population of individuals from different calendar years

Question 7

Selection/anti-selection or adverse selection

Answer 7

taking advantage of inefficiencies in a provider’s pricing basis to secure better terms than might otherwise be justified, normally at the expense of the product provider

Question 8

Spurious selection

Answer 8

Ascribing mortality differences to groups formed by factors that are not the true causes of these differences..

Examples include:
- mortality improvements that are actually due to increasing the strictness of underwriting
- geographical mortality differences that are actually due to a different balance of high and low risk occupations

Question 9

Describe the concept of mortality convergence

Answer 9

Variations in mortality between different subgroups are most noticeable at working ages.

For older populations, mortality in retirement is less variable between different groups.

This convergence of mortality between subgroups at higher ages is referred to as mortality convergence.