Health Statistics and Epidemiology (CHN) PDF

NCM 113: COMMUNITY HEALTH NURSING 2 HEALTH STATISTICS AND United States 12.28 EPIDEMIOLOGY Canada 10.17 Somalia 37.98 Demography - Science which deals with the study of popula...

NCM 113: COMMUNITY HEALTH NURSING 2 HEALTH STATISTICS AND United States 12.28 EPIDEMIOLOGY Canada 10.17 Somalia 37.98 Demography - Science which deals with the study of population sizes, composition Death Rate - Average number of deaths in and distribution in space. a year for every 1000 people in a total population. Population - Refers to the number of Philippines 6.41 people in a given place or areas in a given Japan 11.59 time. United States 8.38 Canada 8.12 Household - Is a person or group of related or unrelated persons who live Natural Increase - Difference between the together in the same dwelling unit, who number of births and the number of acknowledge one adult male or female as Deaths occurring in a population in a the head of the household, who share the specific period of time. same housekeeping arrangements and NI = Births - Deaths (Specified Year) (Specified Year) (Specified Year) who are considered a single unit. SOURCES OF DEMOGRAPHIC Philippines INFORMATION  CBR= 22.28 1. Census— an official and periodic  CDR= 6.41 enumeration of population. Crude Birth Rate Two ways of assigning people during Ex. Compute for Crude Birth Rate Census:  In Kidapawan City, North Cotabato, De jure- when people are assigned there were 4567 births. The total to the place where they usually live population was 125,447. The CBR regardless of where they are at the is 36.4 per 1000 population time of the census. De facto- people usually present Crude Death Rate during time of the census regardless Ex. Compute the Crude Death Rate of their usual place of residence.  In the municipality of Balo-i, Lanao Del Norte, there were 5634 deaths. 2. Sample surveys The total population was 192,310. 3. Registration The CDR is 29.3 per 1000 population 2 METHODS OF MEASURING POPULATION CHANGES Rate of Natural Increase - Difference 1. Comparing the CBR and CDR Between the Crude Birth Rate (CBR) and 2. Comparison by Census Crude Death Rate (CDR) in a specific period of time. Birth Rate - Average number of live births NRI = CBR - CDR in a year for every 1000 people in a total population. DEMOGRAPHIC INDICATORS Philippines 22.28 Japan 6.95 Population Statistics 1 NCM 113: COMMUNITY HEALTH NURSING 2 Sex ratio Dependency ratio Density Population Size Vital Statistics BR (Birth Rate) DR (Death Rate) Population Composition Sex Composition Population Distribution Age Composition Urban Rural Distribution— Age and Sex Composition illustrates the proportion of the people living urban and rural areas Sex Ratio Crowding Index— describes the Number of females to the number of ease by which a communicable males in the population. disease will be transmitted from one Number of female per 1000 male host to another. Divide number of population persons in a house hold to the number of rooms Number of females x 1000 Population Density— will Number of males determine how congested a place is Calculate Sex Ratio and has implications in terms of Males 1,996,355 adequacy of basic health services. It Females 1,930,234 describes how crowded a place is. 967 Females per 1000 Males VITAL HEALTH STATISTICS Age Composition Nurse Function  Median - arrange age from smallest to 1. Collects data the highest, divide population into 2 equal equal parts & identify number in 2. Tabulates data between 3. Analyses data and interprets data Ex. you are trying to decide an activity for 4. Evaluates data a suitable for the majority group of people. 5. Recommends redirection and /or Age of the group are as follows. 12, 8, 13, strengthening of specific areas of 65, 10, 10, 9 health program. Median 8,9,10,10,12,13,65 Rates and Ratio Rate— shows the relationship bet. a Mean/Average vital event and those persons 8+9+10+10+12+13+65 exposed to the occurrence to the =127/7 said event with in a given area and =18 years old specific period of time Ratio— describe relationship between 2 numerical quantities or measures of events without taking 2 NCM 113: COMMUNITY HEALTH NURSING 2 particular considerations to the time IMR = # OF number of deaths in the first year of life in a year x1000 or place. Total number of livebirths Crude or General Rates— rates registered in the same year are referred to the total living population. Maternal Mortality Rate— Specific Rate— the relationship is measures the risk o dying for for a specific population class or causes related to pregnancy, group. childbirth and puerperium. MMR = # number of deaths from maternal Vital Statistics - Refers to the systematic causes registered given year x 1000 study of vital events such as births, illness, total number of livebirths registered in the same year marriages, divorces/separations and deaths. Fetal Death Rate— measures pregnancy wastage. Death of the Uses of Vital Statistics product of conception occurs prior Planning human development to its complete expulsion, Dynamics of reproduction irrespective of duration of Life-tables pregnancy. Risks of dying FDR = # fetal deaths registered in a Population growth dynamics given calendar year x 1000 Population projections Total Number of Live births Monitoring & evaluating registered in a same year interventions Neonatal Death Rate— risk of Can facilitate information for dying the 1st month of life. NDR = # of deaths under 28 days Provision of services for vulnerable of age registered x 1000 populations (i.e. single mothers & number of livebirths reg. children) in the same year Regional & urban/rural comparisons Attack Rate - Measures the risk of Allocation of resources (i.e. health exposure. Useful in epidemiological care, education, & social security) investigation. AR = number of person acquiring the disease x 1000 number of exposed to the same Crude Birth Rate— Natural growth disease in same year and increase of Population. CBR = # OF Registered livebirth in a year x 1000 estimated population in the same year Check Slide 37-39 Crude Death Rate— mortality from Case Fatality Rate - Killing power of the all causes of Population. disease CDR = # OF Registered deaths in a year x 1000 CFR = No. of registered Deaths estimated population in the same year from a specific disease for a given year x 1000 No. of registered cases Infant Mortality Rate— risk of from specific disease in dying during the first year of life. same year Incidence and Prevalence 3 NCM 113: COMMUNITY HEALTH NURSING 2  INCIDENCE RATE— Measures the Determinants frequency of occurrence of the Factors that influence disease or phenomenon during a given period of health events time. Deals only with New Cases. assumption: Disease does not occur IR = No. of New Cases of RANDOMLY particular disease analytic epidemiology provide “why” Registered during a specific period of time x 1000 and “how” to provide evidence to Population at risk of direct, prompt and effective developing the disease Application  PREVALENCE RATE— Measures the applying the knowledge gained by proportion of the population which the studies to community-based exhibits a particular disease at a practice particular time. An outbreak, needs epidemiologic PR = No. of New and old cases judgment of local conditions of a certain disease registered at a given time x 1000 Number of persons examined Objectives of Epidemiology at same time To identify the etiology or the cause of the disease and the risk factors. INTRODUCTION TO BASIC To determine extent of disease EPIDEMIOLOGY found in the community. To study the natural history and Epidemiology prognosis of disease. originated from the Greek words To evaluate existing and new “epi”- meaning on or upon, meaning preventive and therapeutic people and “ logos” meaning study measures and modes of health care of. delivery. is the study of the distribution and To provide foundation for developing determinants of health-related public policy and regulatory states or events in specified decisions relating to environmental populations, and the application of problems. this study to the control of health problems. Uses of Epidemiology Study the health History of the Study population Scientific discipline Assessing the community’s health Data driven and relies on systematic Relevant sources of data: approach  What are actual and potential Basic science of public health health problems? Provide foundation for practical and  Where are they occurring? appropriate public health action  Which populations are at risk? Basic for casual reasoning in public  Which problems are increasing health or decreasing over time?  How do these patterns relate to Distribution public health services available? Frequency Diagnose the Community and the Pattern condition of the people 4 NCM 113: COMMUNITY HEALTH NURSING 2 Assess evaluate the effectivity of 2. Field Investigation health services A phone call to confirm or clarify Completing a clinical picture circumstances of reported case Epidemiologists rely on clinicians Coordinated efforts of people to and laboratorians for proper characterize extent of an epidemic diagnosis but also contribute to or physicians’ understanding of identify cause clinical picture and natural history Objectives for investigations may of disease. vary Core Epidemiology Function 3. Analytic Studies 1. Public Health Surveillance Rigorous methods than surveillance 2. Field Investigation and outbreak investigation 3. Analytic Studies Hallmark of analytic study is use of 4. Evaluation a comparison group 5. Linkages 6. Policy Development 4. Evaluation process of determining, as 1. Public Health Surveillance systematically and objectively as refers to the ongoing, systematic possible, the relevance, effectiveness, collection, analysis, interpretation efficiency, and impact of activities and timely dissemination of health with respect to established goals. data for the planning, implementation and evaluation of Effectiveness refers to the ability of public health program. The use of a program to produce the intended information based from these data or expected results in the field; to disease prevention and health effectiveness differs from efficacy, promotion program completes the which is the ability to produce surveillance cycle in public health. results under ideal conditions. “The essence of public health Efficiency refers to the ability of surveillance is the use of data to the program to produce the monitor health problems to facilitate intended results with a minimum their prevention or control. expenditure of time and resources. 5. Linkages During an investigation an epidemiologist usually participates as either a member or the leader of a multidisciplinary team. Other team members may be laboratorians, sanitarians, infection control personnel, nurses or other clinical staff, and, computer information specialists. 6. Policy Development 5 NCM 113: COMMUNITY HEALTH NURSING 2 Public health workers regularly clues about many diseases have provide input, testimony, and come from comparing geographic- recommendations regarding disease specific mortality rates. control strategies, reportable disease regulations, and health-care policy. Descriptive Epidemiology  Descriptive epidemiology characterizes as to time, place, person through comprehensive characterization. It identifies population at risk for the disease and provide clues about etiology, source and modes of transmission. This will be used to begin Person intervention and prevention Variation in disease rates by person measures. variables suggests differences in the opportunity for exposure to the The W’s of descriptive Epidemiology: agent or differences in their What: Health issue of concern susceptibility once exposed. This Who: Person element pertains to personal Where: Place characteristics which may affect When: Time illness. Epidemic Curve Check slide 66-69 Variability in disease occurrence can also be analyzed from different CONCEPTS OF PUBLIC HEALTH points of view. These observations SURVEILLANCE are organized and illustrated as an Epidemic Curve. Surveillance Surveillance came from “sur” meaning over and “veller” meaning to watch. “close and continuous observation of one or more persons for the purpose of direction, supervision, or control Continued watchfulness over the Place distribution and trends of incidence Disease pattern by place can be [of a disease] through the analyzed by place-related difference systematic collection, consolidation, based on geographic localities or and evaluation of morbidity and characteristics common in a locality. mortality reports and other relevant Examples are urbanicity, economic data.” – by Alexander Langmuir, development and climate type. Early 1963 6 NCM 113: COMMUNITY HEALTH NURSING 2 General application of surveillance to public health problems. Roles of a Nurse in Surveillance 1. Identify, define and measure the health problem of interest 2. Collect and compile data about the problem 3. Analyze and interpret these data 4. Provide these data and their interpretation stakeholders/ program managers 5. Monitor and periodically evaluate the usefulness and quality of National Surveillance System surveillance Check last page (table) Core process of Public Health Surveillance Nurse Function in Epidemiology Maintains surveillance of the occurrence of notifiable disease Coordinates with other members of the health team during outbreaks Participates in case finding and collection of laboratory specimen. Isolates cases or communicable diseases Nursing care teaching & supervises care Teaches household concurrent and terminate disinfection Follow up cases and contacts Education campaign Referral of cases Coordinates with other concerned IDENTIFYING AND SELECTING A community agencies HEALTH PROBLEM FOR Accomplishes reports and keeps SURVEILLANCE records submits it to proper office. a. Public health importance EPIDEMIOLOGICAL INVESTIGATION  Incidence, prevalence, severity, disabilities, morality, Outbreak or an Epidemic socioeconomic impact, Is the occurrence of more cases of Community, outbreak potential, disease than expected in a given Ability to prevent, control, or treat area or among a specific group of Capacity of health systems people over a particular period of Speed and response, economics, time. availability of response, 7 NCM 113: COMMUNITY HEALTH NURSING 2 EPIDEMIC to situations involving Online of Plan for Epidemiological larger numbers of people over a Investigation wide geographic area. 1. Establish fact of presence of OUTBREAK as an epidemic limited Epidemic to localized increase in the  Verify Diagnosis incidence of disease, e.g., village, a. Is the disease that which it is town, or closed institution. reported to be? b. Are all the cases due to the Sporadic same disease refers to a disease that occurs  Reporting infrequently and irregularly. a. Is it reasonably complete? b. Is the data accurate Endemic  Unusual prevalence of the disease refers to the constant presence a. Past experience of the disease and/or usual prevalence of a b. Relation to nature of the disease disease or infectious agent in a population within a geographic area. 2. Establish time and space relationship of the disease Clustering Are cases limited or is an aggregation of cases in a given concentrated by place area over a particular period Relationship by onset of time without regard to whether the number of cases is more than 3. Relations to characteristic of the expected. group community Relation of case by person (age, Even if the current number of reported sex, occupation etc.) cases exceed rhe expected number, the Relation to vital health facilities excess may not necessarily indicate an Relation to food and water outbreak Relation to other cases Increase in cases may be due to the following: 4. Correlation of all data obtained changes in local reporting Build final case and conclusion procedures Provision of control measures changes in the case definition increased interest because of local Steps in Outbreak Investigation or national awareness, 1. Prepare for field work improvements in diagnostic 2. Establish the existence of an procedures outbreak A new physician, infection control 3. Verify the diagnosis nurse, or healthcare facility may 4. Construct a working case definition more consistently report cases 5. Find cases systematically and result of misdiagnosis or laboratory record information error 6. Perform descriptive epidemiology sudden changes in population size 7. Develop hypotheses 8. Evaluate hypotheses epidemiologically 8 NCM 113: COMMUNITY HEALTH NURSING 2 9. As necessary, reconsider, refine, Agent - Infectious microorganism or and re-evaluate hypotheses pathogen: a virus, bacterium, parasite, or 10.Compare and reconcile with other microbe. laboratory and/or environmental Bacteria- Tuberculosis, studies Salmonellosis, Stryptococcal 11.Implement control and prevention infections measures Viruses - Ex. Viral hepatitis A, 12.Initiate or maintain surveillance influenza, viral meningitis 13.Communicate finding Mycoses- diseases caused by fungi (Ex. Ringworm, athlete’s foot, candidiasis) Protozoa- Malaria, Amoebiasis Helminths- Schistosomiasis Characteristics of Infectious Disease Agents: INFECTIVITY - capacity of the agent to enter and multiply in a susceptible host to produce infection or disease. Poliomyelitis Epidemiological Triad and measles are diseases with high a model that describes the infectivity. causation of a disease PATHOGENICITY- capacity of the agent to cause disease in the infected host VIRULENCE- refers to the severity of the disease TOXIGENICITY- capacity of the agent to produce toxin or poison RESISTANCE- ability of the agent to survive adverse environmental conditions ANTIGENICITY- ability of the agent to induce antibody production in the host. Host refers to the human who can get the disease. Example of host factors are: age, race, sex, socioeconomic status, and behaviors (smoking, drug abuse, lifestyle, sexual practices and contraception, eating habits), genetic composition, nutritional and immunologic status, anatomic 9 NCM 113: COMMUNITY HEALTH NURSING 2 structure, presence of disease or medications, and psychological makeup are some of the host factors which affect a person’s susceptibility and response to an agent. Environment refers to the extrinsic factors that affect the agent and the opportunity for exposure. Environmental factors include physical factors such as geology and climate, biologic factors such as insects that transmit the agent, and socioeconomic factors such as crowding, sanitation, and the availability of health services. 10 NCM 113: COMMUNITY HEALTH NURSING 2 Surveillance System Description 1. Philippine Integrated A functional integrated disease surveillance and Disease Surveillance response system that would result in considerable and Response reduction in morbidity, disability and mortality (PIDSR) caused by communicable diseases and other conditions. 2. Event-based Established to complement the indicator-based Surveillance and surveillance of PIDSR in detecting International Response (ESR) Health regulation (IHR) events with rapid reporting, wider scope, and greater geographic spread at a relatively low cost. 3. Field Health Service A major component of the network information Information System sources developed by DOH to enable it to better (FHSIS) manage its nationwide health service delivery activities. This has been designed to peovide the basic service data needed to monitor activities in each programs. 4. National HIV/STI Objectives include: Measure the magnitude of the Surveillance and HIV situation in the Philippines; monitor & Strategic Information evaluate the health sector's overall response to the Unit (NHSSS) HIV epidemic; provide the necessary information for planning programs, improving health service delivery strategies, and health policy development; and assess and enhance the different health information systems' performance in meeting the STI & HIV data needs of the health system. HIV/AIDS Registry includes reported HIV/AIDS cases diagnosed in hospitals, clinics, laboratories and blood banks accredited for HIV screening. This system captures cases who submit themselves for testing. 5. Online National ONEISS is the information system being Electronic Injury implemented by the DOH in support of the injury Surveillance System Program. (ONEISS) 6. Philippine Health Coordinated efforts of Philippine Statistics Statistics (PHS) Authority (PSA), DOH and local health units which summarizes, analyses, interprets and presents statistical data on births, deaths and population estimates and notifiable diseases. 11