Starter

Activity

The aim of this lesson:

• To evaluate [make an appraisal by weighing up the strengths and limitations] life expectancy, infant mortality rate (IMR) and child mortality, HALE (health-adjusted life expectancy), calorie intake, access to safe water and access to health services as indicators of health.

This section contains a range of information and associated weblinks for a number of health indicators. These are not the only sources of information on these indicators and you should supplement this with additional research.

Remember that with any statistical measure, care needs to be taken about the data collection techniques, and the accuracy and nature of their standardisation of data collection. When dealing with the health of an entire nation, this becomes even more significant.

The IB Five

Evaluation Task

You should be able to define each of these terms and outline their value as indicators of overall health. Some of these factors will be explored in more detail in the next section(s) of this Food and Health Unit.

Following the information on each factor, the evaluation task is explained.

Life Expectancy

This can be defined as the average length of time that a person can expect to live, based on key demographic indicators.

How effective do you think it is as a measure of overall health ? Remember the Gapminder work that you did. There are large variations in values between those countries where people live the longest, and those with the shortest life expectancy.

Are people who live to an old age necessarily ‘healthy’?

Age-specific mortality data is needed to fully explore regional variations within a country. Life expectancy figures can be affected by a high Infant Mortality Rate. If people survive infancy they could live much longer than the life expectancy figures suggest. There may also be differences between cohorts (age groups) in the population which relates to improvements over time. It is important to remember that a low life expectancy may be the result of factors that aren’t health related, including conflict, air pollution, natural hazards, sanitation and the locations where people live. There are also ethnic variations within countries. Male life expectancy is generally lower than female life expectancy, so the demographics of an area also play a part. There are various reasons for this, which include lifestyle, increased suicide rate among young men and greater chance of a road traffic accident.

It is also worth remembering that before the Industrial Revolution, many cities in the United Kingdom had a lower life expectancy than the worst-performing countries today. Life expectancy is improved by vaccination programmes, particularly those on a large scale. However, the HIV/AIDS epidemic has dramatically lowered the life expectancy in sub-Saharan Africa.

Infant Mortality Rate (IMR)

This relates particularly to the proportion of babies who die before they reach their first birthday, per 1000 of the population.

It is generally recognised that the early years are a dangerous time, particular in the immediate post-natal period, where access to proper pediatric services may be limited in some regions or countries. These deaths are often easily preventable, if appropriate medical support was available. It is affected by the age of the mother, the nature of the household the child is born into, education and sanitation. Because of this, the indicator is a good measure of the level of development of a country.

Do you remember how early deaths in Burundi dramatically lowered the average life expectancy in the earlier example?

This could be an area to focus on for a statistical improvement, but the scale of births in some countries such as India, means that there is unlikely to be sufficient budget to implement all the measures. There may also be issues with registering births and deaths in some areas which may affect the reliability of figures used in calculations. Large scale migrations, such as the ones caused by the 2011 famine in Somalia which we will return to later in the unit, also complicate the accurate measurement of deaths.

There are also countries, where a significant proportion of the population is under the age of 15. Where countries have a high proportion of young people (or old people) many of the indicators become less reliable.

Health Adjusted Life Expectancy (HALE)

Health-adjusted life expectancy is a variation on the life expectancy featured above. It is a general indicator of the overall health of a population, but is also related to quality of life. There is an adjustment to the average figure for the time that is spent in ill health.

HALE may also be affected by endogenetic factors (from inside) – these include congenital diseases (from birth), and degenerative diseases resulting from old age. A person may be alive, but not in full health for periods of time at various stages during their life.

In addition to the average life expectancy values, it includes some additional statistical data. This works out the equivalent number of years in full health that a newborn child can expect to live based on the current mortality and morbidity rates for the country.

• Disability-adjusted life years (DALYs) measures number of years of potential or productive life, which are lost to poor health or disability.
• YLDs are years lived with a disability

HALE is therefore a measure of quality as well as quantity of life, which perhaps makes it a more effective measure.

The statistics use what is called Sullivan’s method, named after the demographer who identified the appropriate statistical adjustment that was required. The Sullivan health expectancy reflects the current health of a real population adjusted for mortality levels and independent of the age structure. Health expectancy calculated by Sullivan’s method is the number of remaining years, at a particular age, which an individual can expect to live in a healthy state (however health may be defined). For example, in 2004 in Belgium, women at age 65 could expect to live a further 20.0 years of which 12.4 years (62%) would be spent without disability.

Calorie Intake

Calorie intake relates to the energy that is contained in the food that people eat. Although there are minimum recommended calorie intake figures, the ‘type’ of food that is eaten is also significant. Someone who eats a lot of calories from fried fatty foods would potentially be more unhealthy than someone who ate lots of fruit and vegetables and had a lower daily calorie intake. The current recommended calorie intake per day is 2000 for women, and 2500 for men. There are certain areas such as Japan and the Mediterranean which are famed for their ‘healthy’ diet, but which aren’t necessarily high in calories.

Think back to the photo slideshow that you saw at the very start of the unit. Which of those foods would have had a high calorific value, but would not have been particularly healthy?

Identify countries which are well above and below the average for per capita calorie consumption

Access to safe water

Clean water is an essential element of health as not only are diseases spread by drinking contaminated water, but water is also a method of disease transmission for a range of insects and other organisms (some diseases don’t involve drinking water to become ill). Some of these are exogenetic (from outside), which means they are caused by environmental conditions, social habits and hazards.

Over 85% of the world’s population are thought to have access to safe water. Improvements in access to safe water is included in the Millennium Development Goals. There should be access to water that is affordable, in sufficient quantity for people’s needs and available without excessive effort and time required to collect it.

This immediately creates issues for many millions of people. Generally the water supply should be improved i.e. water is available from a tap, or pipe or pumped from a well. One issue with water is that it is not always possible to tell whether it is contaminated and dangerous to drink. When people are forced to drink dirty water, their chances of poor health increase dramatically, and their ability to recover is reduced substantially, as rehydration is required for diseases such as diarrhoea. Water is also involved in the transmission of certain diseases.

The main diseases linked with dirty water are also shown below [click for larger version]

Access to health services

There is uneven access to health care on a local, regional, national and international level. Some countries have free health care for all the population, but an increasing number have insurance based schemes, or require payment for treatment.

A raw figure is the number of people per doctor, or health worker or hospitals, or hospital beds. There may also be the use of figures relating to the number of doctors per 10 000 of the population. It is worth noting that the age structure of an area can impact on the accuracy of the figure.

Some countries are understood to have lower coverage than is required for adequate health care. An additional figure is health expenditure per capita.

Health services that are referred to here can include:

• Maternity services
• Pediatric care (young people)
• Geriatric care (an increasing issue for countries with ageing populations)
• Promotion of family planning measures, including contraception
• HIV AIDS treatments

The IB Five

Evaluation Task

Work with a partner to establish a judgment on each of these six indicators, and an overall judgment on the relative merits of each. Use a 'Plus, Minus and Interesting Chart' to record information about each of the indicators – consider the extent to which they do, or don’t provide a suitable indicator – it is important to include as much detail as possible here – you may wish to use websites to add some figures to enable a direct comparison. Some key words that you can use in your evaluation are included here as a word cloud for possible use.

You should refer to the following factors:

• How accurate is the data that is used, and how is it collected ?
• Can you make comparisons between indicators ?
• What is the data not telling us about the links with health?
• Is each indicator actually measuring health or is it a factor that can be said to affect health? (these data are called proxy data)

Review

The teacher will place you into a group of six people - one representing each of the indicators above. Each person needs to persuade the others that the indicator they are allocated is the ‘best’ one for indicating the overall health of a country.