IDSB04 Chapter 5
Challenges of health data
•Summary statistics of average life expectancy or infant mortality rates do not reflect
variations within counties by social class, geographic location, occupation, and other
•Data costs money and the higher the quality, the greater the cost. In general, where
disease occurrence is highest, the numbers are the least trustworthy.
•The use of health statistics rest on two assumptions:
1.Disease and death are medicalized processes that are certified by trained
medical practitioners and publicly recorded.
2.There is an agreed upon nosology – a disease classification process
universally applied by doctors through common diagnostic procedures. (ICD –
International classification of disease)
Uses and Limitations of Health Data
•Health statistics, including the infant mortality rate, cases of notifiable illnesses,
numbers and causes of deaths, and certain health services, such as immunization
coverage, together with a few socioeconomic, geographic, and other measures,
typically make up the raw material for various health policy decisions.
oCountries such as Cuba and Sweden interpret health policy thought a more
comprehensive array of data such as influence of economics, educational,
occupational and housing conditions on health.
Gauging Trends and Needs
•A primary reason for health data is to track trends in population health status at
the level of countries, geographic regions, and subpopulations (such as particular
age groups or marginalized populations)
•The International Health Regulations (IHR) require that national governments
notify the WHO of cases or outbreaks of certain diseases, and of measures taken to
prevent their spread.
•Under the new IHR – a public health emergency is considered if it (A) constitutes a
public health risk to other states through the international spread of disease; and
(B) potentially requires a coordinated international response.
Limitations on Health Data
•One should always be cautious in interpreting data because it is difficult to define
the metrics, hard to get the numbers right, and there may be pressure on local and
regional officials and ministries of health to distort figures
Types of Health Data
•Population Data: the number of people in a population and their attributes (age sex,
•Vital statistics: Live births, deaths by sex, age, and cause; and marriages
•Health Statistics: Morbidity by type, severity, and outcome
•Health services statistics: Numbers and types of facilities and services available
•Data on social inequalities in health: social factors that lead to inequalities in health
– rate of absolute and relative poverty, levels of education, and occupational
conditions, among others
•Underlie the most health data because they provide the base numbers for
calculating relevant rates and ratios
•Population data are obtained in two ways:
oEnumeration is done by means of a census of the population, ideally every 10
oRegistration involves collecting vital statistics such as births, marriages, and
Census Procedures and costs
•The data obtained from census data permit a population to be characterized by a
variety of classifiers.
•The essential features of a national population census are as follows:
oSponsorship: A legal basis must be established to ensure compliance and
oDefined territory: The boundaries of national and sub national territorial
divisions must be clear
oUniversality: Every person physically present and/or residing in the territory
should be included
oIndividual enumeration: information should be collected form individuals and
oSimultaneity and specified time: the collected date should refer insofar as
possible to a single point in time.
Gauging trends and needs: a primary reason for health data is to track trends in population health status at the level of countries, geographic regions, and subpopulations (such as particular age groups or marginalized populations) Rate of absolute and relative poverty, levels of education, and occupational conditions, among others. Limitations on census data: appraising the completeness and accuracy of census data calls for careful checks and sophisticated techniques. Birth registration: the right to be registered at birth is recognized by different rights and amendments, almost 40% of births in the world are not registered. Classification of diseases and related health problems (icd: the latest edition, icd-10, was adopted by who member states in 1994. Indirect obstetric deaths: deaths resulting from previous existing disease that developed during pregnancy and which was not due to direct causes but which was aggravated by the physiologic effects of pregnancy.