Fluent Essays

Please help me with my discussion on  principles of epidemiology Overview This discussion board is aligned with the module objective “Demonstrate community assessments and apply the principles of epidemiology.” As part of the discussion you will: · Review the concepts of epidemiology in disease control and prevention (p. 70-78). · Apply ecosocial epidemiology paradigm (macro-level) to one of your chosen diagnosis from module 1 written assignment (p.72). Your initial post must be posted before you can view and respond to colleagues, must contain minimum of two (2) references, in addition to examples from your personal experiences to augment the topic. The goal is to make your post interesting and engaging so others will want to read/respond to it. Synthesize and summarize from your resources in order to avoid the use of direct quotes, which can often be dry and boring. No direct quotes are allowed in the discussion board posts. Post a thoughtful response to at least two (2) other colleagues' initial postings. Responses to colleagues should be supportive and helpful (examples of an acceptable comment are: "This is interesting - in my practice, we treated or resolved (diagnosis or issue) with (x, y, z meds, theory, management principle) and according to the literature..." and add supportive reference. Avoid comments such as "I agree" or "good comment." Points: 30 Due Dates: · Initial Post: Fri, Sep 3 by 11:59 p.m. Eastern Standard Time (EST) of the US. · Response Post: Sun, Sep 5 by 11:59 p.m. Eastern Standard Time (EST) of the US - (the response posts cannot be done on the same day as the initial post). References: · Initial Post: Minimum of two (2) total references: one (1) from required course materials and one (1) from peer-reviewed references. · Response posts: Minimum of one (1) total reference: one (1) from peer-reviewed or course materials reference per response. Words Limits · Initial Post: Minimum 200 words excluding references (approximately one (1) page) · Response posts: Minimum 100 words excluding references. Chapter 5 Epidemiology Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. Epidemiology Is … … the study of the distribution and determinants of health and disease in human populations (Harkness, 1995) … the principal science of public health Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 2 Historical Perspective  Investigations of disease pattern in the community; comparing people who had disease or who remained healthy  Person-Place-Time Model  Person: “Who” factors, such as demographic characteristics, health, and disease status  Place: “Where” factors, such as geographic location, climate and environmental conditions, political and social environment  Time: “When” factors, such as times of day, week, or month and secular trends over months and year Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 3 Different Types of Epidemiology  Descriptive Epidemiology  Study of the amount and distribution of disease  Used by public health professionals  Identified patterns frequently indicate possible causes of disease  Analytic Epidemiology  Examine complex relationships among the many determinants of disease  Investigation of the causes of disease, or etiology Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 4 Epidemiological Triangle Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 5 Figure 5-1 Agent of Disease (Etiologic Factors)  Nutritive elements  Excesses, deficiencies  Chemical agents  Poisons, allergens  Physical agents  Ionizing radiation, mechanical  Infectious agents  Metazoa, protozoa, bacteria, fungi, rickettsia, viruses Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 6 Host Factors–Intrinsic Factors (Susceptibility, or Response to Agent)  Genetic  Age  Sex  Ethnic group  Physiological state  Prior immunological experience  Active/, passive  Intercurrent or preexisting disease  Human behavior Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 7 Environmental Factors— Extrinsic Factors… … influence existence of the agent, exposure, or susceptibility to agent  Physical environment  Biological environment  Human populations, flora, fauna  Socioeconomic environment  Occupation, urbanization and economic development, disruption Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 8 Wheel Model of Human-Environment Interaction Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 9 Figure 5-2 Redrawn from Mausner JS, Kramer S: Mausner and Bahn epidemiology: an introductory text, ed 2, Philadelphia, 1985, Saunders. Web of Causation Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 10 Figure 5-3 From Friedman GD: Primer of epidemiology, ed 4, New York, 1994, McGraw-Hill. Ecosocial Approach  Emphasize the role of evolving macro-level socioenvironmental factors along with microbiological process in understanding health and illness (Smith & Lincoln, 2011)  Challenges the more individually focused risk factor approach to understanding disease origins Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 11 Calculation of Rates  Rates are arithmetic expressions that help practitioners consider a count of an event relative to the size of the population from which it is extracted  Number of health events in a specified period  Population in same area in same specified period • Proportion multiplied by a constant (k) • For example, the rate can be the number of cases of a disease occurring for every 1000, 10,000 or 100,000 people in the population  Can make meaningful comparisons Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 12 Morbidity Rates  Incidence rates  New cases or conditions  Attack rate • Number of new cases of those exposed to the disease  Prevalence rates  All cases of a specific disease or condition at a given time Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 13 Prevalence Pot The relationship between incidence and prevalence Figure 5-4 Redrawn from Morton RF, Hebel JR, McCarter RJ: A study guide to epidemiology and biostatistics, ed 3, Gaithersburg, MD, 1990, Aspen Publishers. Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 14 Morbidity Rates (Cont.) Incidence Rate Prevalence Rate Number of existing cases Total Population _____ Number of new cases _in given time period Population at risk in same time period ___75___ 4000–250 × 1000 = 0.02 0.02 × 1,000 = 20 per 1000 per time period 250 4000 = 0.0625 0.0625 × 1000 = 62.5 per 1000 Mortality Rates (routinely collected birth and death rates)  Other rates  Crude rates  Age-specific rates  Age-adjusted rates or standardization of rates  Proportionate mortality ratio (PMR) Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 15 Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 16 Number of deaths in year Total population size _1720_ 200,000 × 100,000 = 0.0086 Number of births in year Total population size _2900_ 200,000 × 100,000 = 0.0145 Concept of Risk  Risk—probability of an adverse event  Risk factor  Refers to the specific exposure factor  Often external to the individual  Attributable risk  Estimate of the disease burden in a population  Relative risk ratio  Divide the incidence rate of disease in the exposed population by the incidence rate of disease in the nonexposed population. Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 17 Use of Epidemiology  Disease prevention  Primary prevention • Health promotion and specific prevention  Secondary and tertiary prevention  Establishing causality  Screening  Surveillance Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 18 Use of Epidemiology (Cont.)  Health services  Used to describe the distribution of disease and its determinants in populations  Study population health care delivery  Evaluate use of community health services  Nurses must apply findings in practice  Incorporate results into prevention programs for communities and at-risk populations  Extend application into major health policy decisions Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 19 Community health nurses should exercise “social responsibility” in applying epidemiological findings, but this will require the active involvement of the consumer. Community health nurses collaborating with community members can combine epidemiological knowledge and aggregate-level strategies to affect change on the broadest scale. Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 20 Epidemiological Methods  Descriptive epidemiology  Focuses on the amount and distribution of health and health problems within a population  Analytic epidemiology  Investigates the causes of disease by determining why a disease rate is lower in one population group than in another Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 21 Analytic Epidemiology  Observational studies  Descriptive purposes  Etiology of disease  No manipulation by investigator  Cross-sectional studies  Sometimes called prevalence or correlational studies  Examine relationships between potential causal factors and disease at a specific time  Impossible to make causal inferences Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 22 Analytic Epidemiology (Cont.)  Retrospective studies  Compare individuals with a particular condition or disease with those who do not have the disease  Data collection extends back in time  Prospective studies  Monitor a group of disease-free individuals to determine if and when disease occurs  Cohort shares a common experience within a defined time period  Monitors cohort for disease development Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 23 Analytic Epidemiology (Cont.)  Experimental design  Also called a Randomized Clinical Trial (RCT) • Subjects assigned to experimental or control group • Apply experimental methods to test treatment and prevention strategies • Ethical considerations with human subject rights review  Also useful for investigating chronic disease prevention Copyright © 2015, 2011, 2007, 2001, 1997, 1993 by Saunders, an imprint of Elsevier Inc. 24