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Community Health Assessment Part I: Measuring Health. NMDOH Community Health Assessment Program (CHAP). Overview. Community Health Assessment What is it? Measurement basics Common public health measures. Public Health Assessment. The core functions of government in public health:
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Community Health Assessment Part I: Measuring Health NMDOH Community Health Assessment Program (CHAP)
Overview • Community Health Assessment • What is it? • Measurement basics • Common public health measures New Mexico Department of Health
Public Health Assessment • The core functions of government in public health: • to develop policy that supports the health of populations, • to assure access to health care and the quality of that care, and • to assess the health status of the population. Institute of Medicine; Committee for the Study of the Future of Public Health; Division of Health Care Services (1988) The Future of Public Health. Washington, D.C.: National Academies Press. New Mexico Department of Health
Assessment Function of Public Health • Assessmentis the regular andsystematic collection, assembly, analysis, and dissemination of information about the health of a community. Institute of Medicine (1988) The Future of Public Health, National Academies Press. New Mexico Department of Health
Assessment “An understanding of the determinants of health and of the nature and extent of community need is a fundamental prerequisite to sound decision-making about health. Accurate information serves the interests both of justice and the efficient use of available resources. Assessment is therefore a core governmental obligation in public health.” (emphasis mine) Institute of Medicine (1988) The Future of Public Health, National Academies Press. New Mexico Department of Health
Health • World Health Organization definition of health: “Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.” WHO Definition of Health, downloaded from http://www.who.int/about/definition /en/print.html on 7/6/09. New Mexico Department of Health
Fundamental Considerations in Measuring Community Health Status
Measuring Community Health • Health Conditions: Medical, social, and economic • Not all “Health-related Conditions” are medical (e.g., poverty, education, environment) • Population at Risk • Include demographic measures to help identify at-risk populations within the community. (e.g., age, sex, language) New Mexico Department of Health
Measuring Community Health • Clinical prevention, early detection • Certain conditions are interesting primarily because they may be prevented or detected early, before complications arise (e.g., vaccine-preventable diseases, dental caries, breast cancer) Mooney, A. and Rives, N.W. (1978). Measures of community health status for health planning. Hospital Research and Educational Trust, (Summer), pp 129-145. New Mexico Department of Health
Types of Prevention • Primary Prevention • Reducing the incidence of a condition (e.g., vaccine) • Secondary Prevention • Reducing the complications of an illness (e.g., treating high blood pressure) • Tertiary Prevention • Reducing levels of residual disability or other long-term effects, given that an illness has already occurred (e.g., managing diabetes) New Mexico Department of Health
Morbidity versus Mortality • Morbidity is another term for illness. Morbidities are not deaths, and occur among the population of living persons. Examples of morbidities include Alzheimer's disease, diabetes, and traumatic brain injury. • Mortality is another term for death. A mortality rate is the number of deaths due to a disease divided by the number of persons in the population. A mortality rate is typically multiplied by a factor of ten (e.g, 100,000) so that the rate may be expressed as a whole number. New Mexico Department of Health
Incidence Versus Prevalence • Incidence is the number of new cases (of disease) in a given period of time. (e.g., cancer incidence is the number of new cases of cancer during the time period) • Prevalence is the number of existing cases (e.g., of a disease or risk factor) in a given period of time. (e.g., prevalence of high blood pressure, prevalence of obesity) New Mexico Department of Health
Measurement Basics • Example: Age Distribution of This Class. • On a blank sheet of paper, write your age. (If you don’t want to divulge your age, you can write a different age.) • Arrange yourselves in the back and sides of the classroom, from youngest to oldest. • Where there is more than one person of the same age, stand in front of one another. • Where there are gaps, with no person of a certain age, leave a space for that age. New Mexico Department of Health
Mode: 37 Median: 41.5 Mean: 48.8 Age Distribution Histogram New Mexico Department of Health
Age Distribution Histogram New Mexico Department of Health
Distribution “Curve” New Mexico Department of Health
Distribution “Curve” New Mexico Department of Health
The “Normal” Distribution New Mexico Department of Health
Measurement and “True Scores” • Why do we look at data? • Sometimes we just use the number at face value. “If one obstetrician can serve 100 pregnant women and the births of their babies in a given year, and our community has had 883 births, on average, in the last 5 years, then we will need to ensure availability of 9 O.B.s for the women of this community.” New Mexico Department of Health
Measurement and “True Scores” • More often, we use the data to tell us something about RISK. • Which of these communities has the higher diabetes death risk? New Mexico Department of Health
Measurement and “True Scores” • Which of these communities has the higher diabetes death risk? New Mexico Department of Health
Measurement and True Scores • What has this got to do with measurement and true risk? • Each of the three communities in the previous examples has an underlying risk for diabetes death. • The 3 communities have different RISK levels because of a variety of factors, including lifestyle (diet and exercise), medical care (diagnosis and disease management), and other factors. New Mexico Department of Health
Measurement and True Scores • What has this got to do with measurement and true risk? • The OBSERVED number of diabetes deaths, and the diabetes death rates are a MEASURE of the diabetes death RISK. • The TRUE RISK is the actual risk level. It can not be measured directly. We use death data to estimate, or INFER the diabetes death risk. New Mexico Department of Health
Measurement and True Scores • What has this got to do with measurement and true risk? • While the actual risk changes slowly, in response to changes in the contributing factors, the measure (observed diabetes deaths) can very considerably from year to year, especially in a small population. New Mexico Department of Health
Trend Lines for Two Communities New Mexico Department of Health
Calculating Some Statistics • Counts • Incidence is the number of new cases (e.g., of disease) in a given period of time. • Prevalence is the number of existing cases (e.g., of a disease or risk factor) in a given period of time. New Mexico Department of Health
Count • Get a count of the prevalence of green M&Ms in your sample. (Count the green M&Ms.) New Mexico Department of Health
Calculating Some Statistics • Rate • A rate is a fraction, in which the numerator is the number of people (or M&Ms) among whom an event occurred during a certain period of time, and the denominator is the total number of people (or M&Ms) in the population at risk for the same period of time. Rates are typically multiplied by some factor of ten so that the result is a whole number. New Mexico Department of Health
Example Formula # Green M&Ms Total # M&Ms in the package 8 25 = 0.32 Rate • Count the green M&Ms. • Count the total number of M&Ms. • Divide the number of green M&Ms by the total number of M&Ms. New Mexico Department of Health
Calculating Some Statistics • Percentage • A percentage is a rate in which the quotient is multiplied by 100. • Using your green M&M prevalence rate, multiply it by 100 to get the percentage of green M&Ms in your sample. New Mexico Department of Health
Confidence Interval • A confidence interval is a range around a measurement that conveys how precise the measurement is. • the possible range around the estimate • how stable the estimate is • A stable estimate is one that would be close to the same value if the measurement were repeated. • An unstable estimate is one that would vary from one measurement to another. New Mexico Department of Health
Trend Lines for Two Communities New Mexico Department of Health
Trend Lines for Two Communities New Mexico Department of Health
Trend Lines for Two Communities New Mexico Department of Health
Community Health Assessment Part 2: Documenting Health Status NMDOH Community Health Assessment Program (CHAP)
Population-Based • Population-based: Covers the entire population. • Population-based: • Residents of New Mexico • Children in Mora County • Why are these NOT Population-based? • Clinic patients • WIC recipients New Mexico Department of Health
Mortality Risk Inferred from Mortality Data • Life expectancy • Death Rates • Years of Potential Life Lost • YPLL stands for "Years of Potential Life Lost," and is a measure of premature mortality. It is calculated as the difference, across all persons in a population, between the actual age at death and age 65. It can also be calculated as the sum of the remaining years of life expectancy for all decedents in a population. New Mexico Department of Health
Morbidity Risk Inferred from Mortality Data • Cause-specific deaths • Diabetes-related deaths • Alcohol-related motor vehicle crash deaths • Heart disease deaths • Chronic liver disease and cirrhosis • Suicide deaths • Chronic obstructive pulmonary disease (emphysema) New Mexico Department of Health
Calculating a Death Rate New Mexico Department of Health
Calculating a Death Rate • A rate has four components: • A specified time period. • The numerator, the number of people in whom an event occurred during a given period of time, and • The denominator, the total number of people in the population at risk for the same period of time. This is also referred to as the "person-years at risk." • A constant. The result of the fraction is usually multiplied by some factor of 10 (such as 100,000), so that the rate may be expressed as a whole number. New Mexico Department of Health
The Numerator: Causes of Death • National Center for Health Statistics, 50 Leading Causes of Death • In order to provide a consistent ranking standard the NCHS (National Center for Health Statistics, part of the CDC) prepared a list of 113 selected causes of death. The NCHS 50 leading causes of death are taken from the list of 113. For more information about the NCHS rankings, see Cause of Death Ranking on the NCHS website. New Mexico Department of Health
The Numerator: Causes of Death New Mexico Department of Health
The Numerator: Causes of Death New Mexico Department of Health
The Numerator: Causes of Death New Mexico Department of Health
International Classification of Disease, Version 10 (ICD-10) New Mexico Department of Health
The Numerator: Causes of Death New Mexico Department of Health
Calculating a Death Rate New Mexico Department of Health
Calculating a Death Rate • The calculation for the death rate for Heart Disease in Region 1 looks like this: • Do the division: • Multiply by the ‘constant’: New Mexico Department of Health