Topic 2: Global Health Metrics Flashcards
Why do we need health metrics?
- Monitor progress already made in global health,
- Gain insight on differences and remaining challenges
- Design effective approaches to mitigate existing and emerging health challenges
How do we measure health and disease?
- First task is to count occurrence
- Most useful approach depends on the nature of the condition and the purpose for which it is counted – counts versus rates (or absolute versus relative measure).
How do we measure mortality?
- Traditionally, mortality has been the most important indicator of the health status of a population.
- The simplest measure of mortality at the population level is the crude death rate (CDR)
- The crude death rate, also called the mortality rate, is the annual number of deaths per 1000 people (other units, such as per 100,000 people are also used).
What is the crude birth rate (CBR)?
is the annual number of births per 1000 people in the total population.
What is crude death rate (CDR)?
The simplest measure of mortality at the population level is the crude death rate (CDR
What does: CBR>CDR mean?
Natural increase… population increase (in the absence of excess emigration).
What is Age standardization?
Technique used to allow populations to be compared when the age profiles on the populations are quite different.
Explain life expectancy?
represents the average number of years that a newborn is expected to live if current mortality rates continue to apply..
If life expectancy is a refined measure why is not used routinely?
• Iife expectancy estimates are generated using life tables age, sex data complete birth and death registration/reliable population data
o It doesn’t account the health aspects
• More refined mortality estimates also require the causes from which people died from cause-specific life tables.
What is HALE?
Healthy life expectancy (HALE) summarizes expected number of years that an average individual born into the population can expect to live without disability
How to calculate HALE?
• the years of ill health are weighted according to severity and subtracted life expectancy.
What is Cumulative incidence, or incidence proportions?
The number of a new cases of the disease occurring in a time period divided by the total number of people at risk for that disease in that time period.
What are the necessary components of incidence proportions?
♣ Definition of the onset of event (i.e. NEW cases of diseases)
♣ A defined population (i.e. every one included in the denominator must have the potential to become part of the group that is counted in the numerator) and
♣ A particular time period (i.e. any time unit can be used by needs to be consistent for denominator and numerator).
Define incidence density?
• ew cases of the disease per unit of person-time
o Most useful measure of disease frequency
Explain prevalence rate.
is a measure of present status rather than on newly occurring disease. It is defined as the number of total existing cases, whether newly-diagnosed or long-established, divided by the total number of people in the population at the time the prevalence is measured.
Define YLD’s
Years Lived with Disability = the burden to a population from nonfatal health conditions that cause significant short-or long-term reduction in health status.
Define YLL’s
Years of Life Lost = the burden from premature mortality in a population.
Define DALY
Disability-adjusted life year (DALY) = the total burden of disease in a population from both premature deaths and disability.
Explain: DALY = YLL + YLD
- Indicates losses due to illness, disability and premature death in a population.
- A health-gap measure.
- Main issue (weights) used in measuring severity while benefit is it highlights the high burden of non-fatal causes.
If life expectancy, HALE and DALYs are refined measures why is it not that they are not used routinely?
- DALYs and HALE further require information on health status of populations.
- Nevertheless, in many low-income countries birth and death registration data are either unavailable or unreliable – completeness and coverage issues.
Describe demographic transition
describes the change in birth and death rates that historically have accompanied the shift from a traditional society to a more modern society.
Explain Health transitions or epidemiological transition
describes a population shift from a stage in which undernutrition deficiencies are prevalent to a stage in which overweight and obesity are the dominant nutritional disorders.
Explain Demographic Transition
• The theory of demographic transition is based on the actual population trends of advanced countries of the world. This theory states that every country passes through different stages of population development.
• According to Blacker, the five stages are:
o High stationary
o Early expanding
o Late expanding
o Low stationary
o Declining phase
What are the three major stages of episode of epidemiologic transition?
o Age of pestilence and famine: mortality is high and fluctuating (life expectancy 20-40 years); premodern pattern of health; major determinants are: epidemic/infectious diseases, famine and wars.
o Age of Receding pandemics: steady decline of infectious disease, epidemic peaks become less frequent or disappear (life expectancy 30-50 years).
o Age of degenerative and manmade diseases: mortality continues to decline and eventually approaches stability at a relatively low level; increase in chronic disorders associated with ageing (cardiovascular and cancer);
Explain nutritional transition
• Shift from a stage in which undernutrition and nutrient deficiencies are prevalent to an intermediate stage in which undernutrition and obesity are both problems in the population to a stage in which overweight and obesity are the dominant nutritional disorders.
