Describe the indicators of health.

Nature and Uses of Health Indicators

• Their uses — to measure the health status of a population; to compare populations, regions and countries; to assess health care needs and allocate resources; to monitor and evaluate programmes; and to set and track targets
• The characteristics OF A good indicator are frequently examined and should be listed — it should be valid (it measures what it claims to measure); reliable and objective (the same answer when measured by different people); sensitive (it changes when the situation changes); specific (it reflects changes only in the condition of interest); feasible (obtainable with available resources); and relevant to the question being asked
• Mortality indicators — these have the advantage of being widely available and relatively reliable, but the disadvantage of reflecting only the extreme outcome and saying nothing about morbidity or quality of life
• Crude death rate — deaths per 1000 population per year; its weakness is that it is heavily influenced by the age structure, so a developed country with many elderly people may have a higher crude death rate than a developing country with a young population — which is why rates must be age-standardised before they are compared
• Infant mortality rate (IMR) — deaths under 1 year per 1000 live births in a year. It is regarded as one of the most sensitive indicators of the overall health and socio-economic status of a population, because it is influenced by maternal health, nutrition, sanitation, female literacy, income and access to care together
• It divides into neonatal (under 28 days) and post-neonatal (28 days to 1 year) — and the neonatal component reflects the quality of antenatal and obstetric care, while the post-neonatal component reflects the environment, nutrition and infection
• As the IMR falls, the neonatal proportion rises, because environmental deaths are the easier ones to prevent — which is why further reduction in India now depends chiefly on newborn care
• Under-five mortality rate — a good indicator in high-mortality settings; and perinatal mortality rate, which includes stillbirths from 28 weeks plus early neonatal deaths (under 7 days) per 1000 total births, and is the best indicator of obstetric care
• Maternal mortality ratio — maternal deaths per 100,000 live births; it is the indicator showing the widest disparity between rich and poor countries, and is therefore a powerful measure of inequity
• Note the distinction — the maternal mortality ratio uses live births as the denominator, the rate uses women of reproductive age
• Life expectancy at birth — the average number of years a newborn would live if current age-specific mortality persisted. It is a good summary indicator and is not affected by the age structure, which is its advantage over the crude death rate
• Case fatality rate and proportional mortality; and disease-specific mortality

Morbidity, Composite and Other Indicators

• Morbidity indicators exist because mortality alone misses non-fatal disease, which is most disease
• Incidence — new cases in a defined period, which measures the risk of developing disease and is the indicator for acute disease and for evaluating prevention
• Prevalence — all cases (new and old) at a point or over a period, which measures the burden of disease and is used for planning services
• The relationship, which must be known — prevalence = incidence × duration (for a stable situation)
• Its implication is important and counter-intuitive: a treatment that prolongs life without curing increases prevalence, so a rising prevalence may indicate success rather than failure — as with antiretroviral therapy for HIV
• Other morbidity indicators — notification rates, attendance and admission rates, duration of stay, and disability rates
• Disability indicators were developed to capture the fact that people may live many years in poor health:
• Sullivan’S index — expectation of life free of disability
• HALE (Health-Adjusted Life Expectancy) — the years expected to be lived in full health
• DALY (disability-adjusted life year) — the key composite indicator, representing one lost year of healthy life
• DALY = YLL + YLD — years of life lost due to premature mortality plus years lived with disability
• The point of the DALY is that it puts death and disability on a single scale, so that conditions that kill few but disable many — depression, back pain, blindness, hearing loss — become visible to planners in a way that mortality statistics never allowed. This transformed global health priorities
• QALY (quality-adjusted life year) — the counterpart used in economic evaluation, weighting years of life by quality; DALYs are averted (a benefit) whereas QALYs are gained
• Nutritional indicators — birth weight, low birth weight rate, stunting, wasting, underweight, anthropometry and anaemia prevalence
• Health care delivery indicators — doctor-population and nurse-population ratios, bed-population ratio, doctor-nurse ratio, and population per centre
• Utilisation indicators — immunisation coverage, antenatal care coverage, institutional deliveries, contraceptive prevalence rate, and bed occupancy
• Social and mental health indicators — literacy rate, per capita income, dependency ratio, housing, suicide rate, crime and substance abuse
• Environmental indicators — access to safe water and sanitation, and air quality
• Composite indices:
• The human development index (HDI) combines life expectancy at birth, education (mean and expected years of schooling) and gross national income per capita — a reminder that health, education and income are inseparable
• The physical quality of life index (PQLI) combines infant mortality, life expectancy at one year and literacy, each scaled 0 to 100 and averaged; notably it excludes income deliberately, to show that wealth and well-being are not the same
• The limitations of all indicators must be acknowledged — they depend on the completeness and quality of registration and reporting, which is a serious problem in India, where civil registration of births and deaths is incomplete and medical certification of the cause of death covers only a minority
• Averages conceal inequality — a national IMR of 30 may hide a range from under 10 in Kerala to over 40 elsewhere; so indicators should always be disaggregated by state, district, sex, caste, wealth quintile and rural or urban residence
• The main sources of these data in India — the census (decennial); the sample registration system (SRS), which provides reliable birth, death and infant mortality rates; the civil registration system; the national family health survey (NFHS); the Health Management Information System; disease surveillance (IDSP); and hospital and programme records
• The infant mortality rate is the most sensitive indicator, since it responds to nutrition, sanitation, literacy and income together
• Crude death rates must be age-standardised before comparison, or a developed country appears less healthy than a developing one
• Life expectancy is not affected by age structure, which is its advantage over the crude death rate as a summary
• The neonatal share rises as infant mortality falls, because environmental deaths are the easier ones to prevent
• Further reduction in India depends on newborn care, which follows directly from that shift in composition
• Perinatal mortality is the best indicator of obstetric care, combining stillbirths with early neonatal deaths
• Maternal mortality shows the widest global disparity of any health indicator, which makes it a powerful measure of inequity
• The ratio uses live births and the rate uses women, which is a distinction examiners like and students confuse
• Prevalence equals incidence times duration, which is the relationship to state and then to interpret
• Rising prevalence may mean success, since treatment that prolongs life without curing increases it
• Incidence measures risk and prevalence measures burden, so one evaluates prevention and the other plans services
• The DALY puts death and disability on one scale, which made depression, back pain and blindness visible to planners
• DALYs are averted and QALYs are gained, which is the simplest way to keep the two apart
• DALY equals years of life lost plus years lived with disability, and the formula should be stated rather than described
• PQLI deliberately excludes income, to demonstrate that wealth and well-being are not the same thing
• HDI combines health, education and income, a reminder that the three are inseparable in development
• Averages conceal inequality, so indicators must be disaggregated by state, sex, caste, wealth and residence
• Civil registration in India is incomplete, and medical certification of cause of death covers only a minority
• The Sample Registration System provides reliable rates for births, deaths and infant mortality where civil registration falls short
• A good indicator is valid, reliable, sensitive and feasible, and listing these characteristics is a standard sub-question
• Sensitivity and specificity apply to indicators too, not only to diagnostic tests, and mean the same things
• Mortality indicators miss most disease, since most illness does not kill, which is why morbidity indicators exist
• Utilisation indicators measure service performance, such as immunisation coverage and institutional delivery rates
• Literacy and income are health indicators, because the social determinants are part of what is being measured