Epidemiology EPI 2004 Handout Lecture 2 PDF

EPIDEMIOLOGY EPI 2004 LECTURER: MRS. C. BECKFORD HARVEY RN,RM,PHN,MPH,THM,( PHD CANDIDATE) OBJECTIVES AT THE END OF THE UNIT, THE STUDENT SHOULD: DEFINE THE TERMS EPIDEMIOLOGY AND THE EPIDEMIOLOGIC APPROACH. DISCUSS THE AIMS, USES AND VARIABLES IN EPIDEMIOLOGY. EXPLAIN EACH PHASE...

EPIDEMIOLOGY EPI 2004 LECTURER: MRS. C. BECKFORD HARVEY RN,RM,PHN,MPH,THM,( PHD CANDIDATE) OBJECTIVES AT THE END OF THE UNIT, THE STUDENT SHOULD: DEFINE THE TERMS EPIDEMIOLOGY AND THE EPIDEMIOLOGIC APPROACH. DISCUSS THE AIMS, USES AND VARIABLES IN EPIDEMIOLOGY. EXPLAIN EACH PHASE OF THE EPIDEMIOLOGIC APPROACH. INTERPRET THE KEY COMPONENTS OF EPIDEMIOLOGIC DATA. OBJECTIVES ANALYSE THE SOURCES OF INFORMATION FOR DISEASE SURVEILLANCE/EPIDEMIOLOGY DATA CALCULATE VARIOUS RATES AND RATIOS RELATED TO EPIDEMIOLOGY DISTINGUISH BETWEEN INCIDENCE AND PREVALENCE RATES EXAMINE SCREENING TESTS REGARDING THEIR VALIDITY RELIABILITY AND AS A MEASURE TO DETECT DISEASES. DESCRIBE THE TYPES AND METHODS OF SURVEILLANCE. CONSTRUCT TABLES AND FIGURES USED TO REPRESENT EPIDEMIOLOGY DATA DISCUSS THE AIMS, USES AND VARIABLES IN EPIDEMIOLOGY CONT’D WHAT IS A VARIABLE AND WHY IS IT IMPORTANT? RATIO VARIABLE NOMINAL/ CATEGORICAL VARIABLE ORDINAL VARIABLE INTERVAL VARIABLE DISCRETE VARIABLE BINARY/DICHOTOMOUS VARIABLE CONTINUOUS VARIABLE SEE HANDOUT DISCUSS THE AIMS, USES AND VARIABLES IN EPIDEMIOLOGY CONT’D VARIABLES IN EPIDEMIOLOGY: PERSON VARIABLES IMPORTANCE: TO DETERMINE HIGH RISK GROUPS PLACE VARIABLES GEOGRAPHIC LOCATION IMPORTANCE: PROVIDES POWERFUL EVIDENCE ABOUT THE CAUSE AND TRANSMISSION OF THE AGENT.  DISCUSS THE AIMS, USES AND VARIABLES IN EPIDEMIOLOGY CONT’D TIME VARIABLES SEASONALITY TRENDS OVER TIME EXPOSURE VARIABLES: LIFESTYLE FACTORS BIOLOGICAL FACTORS SOCIAL FACTORS  EXPLAIN EACH PHASE OF THE EPIDEMIOLOGIC APPROACH. PHASES - DESCRIPTIVE, ANALYTICAL, EXPERIMENTAL, AND EVALUATION PHASE 1 – DESCRIPTIVE EPIDEMIOLOGY - IDENTIFYING THE PROBLEM EXPLAIN EACH PHASE OF THE EPIDEMIOLOGIC APPROACH DESCRIPTIVE CONT’D KEY ELEMENTS: PERSON PLACE TIME NEVER TRIES TO ANSWER THE “ WHY” QUESTION. EXPLAIN EACH PHASE OF THE EPIDEMIOLOGIC APPROACH PHASE 2 - ANALYTICAL FOCUSES ON DETERMINING THE CAUSES AND ESTABLISHING ASSOCIATIONS.  EXPLAIN EACH PHASE OF THE EPIDEMIOLOGIC APPROACH PHASE 3- EXPERIMENTAL THIS IS WHERE INTERVENTIONS ARE DEVELOPED, TESTED, AND IMPLEMENTED.  EXPLAIN EACH PHASE OF THE EPIDEMIOLOGIC APPROACH PHASE 4- EVALUATION EVALUATION HELPS ENSURE THAT RESOURCES ARE USED EFFECTIVELY, INTERVENTIONS ACHIEVE THEIR INTENDED OUTCOMES, AND PUBLIC HEALTH STRATEGIES ARE INFORMED BY EVIDENCE.  TYPES OF EVALUATION IN EPIDEMIOLOGY FORMATIVE EVALUATION PROCESS EVALUATION OUTCOME EVALUATION IMPACT EVALUATION  FORMATIVE EVALUATION IDENTIFIES POTENTIAL ISSUES, FEASIBILITY, AND STAKEHOLDER NEEDS, AND HELPS IN DESIGNING THE INTERVENTION EFFECTIVELY. CONDUCTED DURING THE DEVELOPMENT OR EARLY IMPLEMENTATION OF A PROGRAM OR INTERVENTION TO REFINE AND IMPROVE IT BEFORE FULL-SCALE IMPLEMENTATION.  PROCESS EVALUATION LOOKS AT THE FIDELITY OF IMPLEMENTATION, THE REACH OF THE PROGRAM, AND THE RESOURCES USED. ASSESSES HOW A PROGRAM OR INTERVENTION IS BEING IMPLEMENTED AND WHETHER IT IS REACHING THE INTENDED POPULATION AS PLANNED.  OUTCOME EVALUATION EVALUATES WHETHER THE INTERVENTION ACHIEVED ITS SPECIFIC OBJECTIVES OR OUTCOMES, SUCH AS CHANGES IN KNOWLEDGE, BEHAVIOR, OR HEALTH STATUS. MEASURES THE SHORT-TERM AND IMMEDIATE EFFECTS OF A PROGRAM OR INTERVENTION ON THE TARGET POPULATION.  IMPACT EVALUATION LOOKS AT THE BROADER CHANGES IN HEALTH OUTCOMES, SOCIAL DETERMINANTS OF HEALTH, OR OVERALL WELL-BEING THAT RESULT FROM THE INTERVENTION. EXAMINES THE LONG-TERM EFFECTS AND OVERALL IMPACT OF A PROGRAM OR INTERVENTION, INCLUDING UNINTENDED CONSEQUENCES. SURVEILLANCE  DESCRIBE THE TYPES AND METHODS OF SURVEILLANCE SURVEILLANCE IN EPIDEMIOLOGY REFERS TO THE CONTINUOUS, SYSTEMATIC COLLECTION, COLLATION, ANALYSIS, INTERPRETATION, AND DISSEMINATION OF HEALTH-RELATED DATA. THE PRIMARY GOAL OF SURVEILLANCE IS TO MONITOR THE HEALTH OF POPULATIONS, DETECT AND RESPOND TO POTENTIAL PUBLIC HEALTH THREATS, TRACK DISEASE TRENDS OVER TIME, AND EVALUATE THE EFFECTIVENESS OF PUBLIC HEALTH INTERVENTIONS. BY MAINTAINING A CONSTANT FLOW OF INFORMATION, SURVEILLANCE SYSTEMS HELP PUBLIC HEALTH AUTHORITIES MAKE INFORMED DECISIONS ABOUT DISEASE PREVENTION, CONTROL STRATEGIES, AND RESOURCE ALLOCATION. SURVEILLANCE CAN FOCUS ON INFECTIOUS DISEASES, CHRONIC CONDITIONS, INJURIES, ENVIRONMENTAL EXPOSURES, AND OTHER HEALTH-RELATED EVENTS. METHODS OF SURVEILLANCE PASSIVE SURVEILLANCE ACTIVE SURVEILLANCE HOSPITAL ACTIVE SURVEILLANCE) SENTINEL SURVEILLANCE SYNDROMIC SURVEILLANCE LABORATORY-BASED SURVEILLANCE  PASSIVE SURVEILLANCE DATA IS ROUTINELY COLLECTED FROM HEALTHCARE PROVIDERS, LABORATORIES, OR OTHER REPORTING SOURCES WITHOUT ACTIVE SOLICITATION. THE DATA IS THEN SUBMITTED TO PUBLIC HEALTH AUTHORITIES. KEY FEATURES: VOLUNTARY REPORTING: HEALTHCARE PROVIDERS, HOSPITALS, AND LABS REPORT CASES OF SPECIFIC DISEASES OR HEALTH EVENTS TO PUBLIC HEALTH AGENCIES AS REQUIRED BY LAW OR REGULATION. LOW COST: IT IS LESS RESOURCE-INTENSIVE AND RELATIVELY EASY TO MAINTAIN BECAUSE IT RELIES ON EXISTING DATA SOURCES. LIMITATIONS: MAY UNDERREPORT CASES BECAUSE IT DEPENDS ON HEALTHCARE PROVIDERS' COMPLIANCE AND THE HEALTH-SEEKING BEHAVIOR OF THE POPULATION.  ACTIVE SURVEILLANCE ACTIVE SURVEILLANCE INVOLVES PROACTIVE EFFORTS BY PUBLIC HEALTH AUTHORITIES TO IDENTIFY CASES OR HEALTH EVENTS. ( EXAMPLE - HOSPITAL ACTIVE SURVEILLANCE) THIS MAY INCLUDE DIRECT CONTACT WITH HEALTHCARE PROVIDERS, REGULAR SURVEYS, OR VISITS TO HEALTHCARE FACILITIES TO COLLECT DATA. INVOLVES ACTIVE DATA COLLECTION PUBLIC HEALTH OFFICIALS ACTIVELY SEEK OUT CASES, ENSURING MORE COMPLETE AND ACCURATE DATA COLLECTION. IS MORE RESOURCE-INTENSIVE-REQUIRES MORE RESOURCES, INCLUDING PERSONNEL AND TIME, BUT OFTEN RESULTS IN MORE RELIABLE DATA. HIGH SENSITIVITY - MORE LIKELY TO DETECT CASES, INCLUDING MILD OR ASYMPTOMATIC ONES THAT MIGHT BE MISSED IN PASSIVE SURVEILLANCE.  SENTINEL SURVEILLANCE SENTINEL SURVEILLANCE USES SELECTED INSTITUTIONS, HEALTHCARE PROVIDERS, OR COMMUNITIES (REFERRED TO AS "SENTINEL SITES") TO MONITOR AND COLLECT DATA ON SPECIFIC DISEASES OR HEALTH INDICATORS. INVOLVES TARGETED DATA COLLECTION- FOCUSES ON HIGH-QUALITY DATA FROM A SMALL, REPRESENTATIVE SAMPLE OF REPORTING SITES. IT IS EFFICIENT IN THAT IT PROVIDES TIMELY DATA THAT CAN BE USED FOR EARLY WARNING OF OUTBREAKS OR MONITORING TRENDS WITHOUT THE NEED FOR SYSTEM-WIDE DATA COLLECTION. HOWEVER IT HAS ITS LIMITATIONS.  LABORATORY-BASED SURVEILLANCE LABORATORY-BASED SURVEILLANCE INVOLVES THE COLLECTION AND ANALYSIS OF DATA FROM LABORATORY TESTS TO MONITOR THE PREVALENCE OF DISEASES, ESPECIALLY THOSE THAT REQUIRE CONFIRMATION THROUGH LABORATORY DIAGNOSTICS. EXAMPLES ? ACCURATE DIAGNOSIS- PROVIDES DATA BASED ON CONFIRMED CASES, ENSURING THAT SURVEILLANCE IS BASED ON PRECISE AND RELIABLE DIAGNOSTIC CRITERIA. SPECIALIZED SURVEILLANCE: OFTEN USED FOR DISEASES THAT REQUIRE SPECIFIC LABORATORY TESTS FOR DIAGNOSIS, SUCH AS HIV, TUBERCULOSIS, OR BACTERIAL INFECTIONS.  SYNDROMIC SURVEILLANCE SYNDROMIC SURVEILLANCE FOCUSES ON THE EARLY DETECTION OF OUTBREAKS BY MONITORING NON- SPECIFIC HEALTH INDICATORS (SUCH AS SYMPTOMS OR BEHAVIORS) THAT MAY INDICATE THE ONSET OF AN EPIDEMIC BEFORE A SPECIFIC DIAGNOSIS IS MADE. REAL-TIME DATA: OFTEN USES DATA FROM EMERGENCY DEPARTMENTS, PHARMACIES, OR EVEN ABSENTEEISM RECORDS TO DETECT UNUSUAL PATTERNS THAT MIGHT SUGGEST AN OUTBREAK. EARLY DETECTION - CAN PROVIDE EARLY WARNING OF POTENTIAL PUBLIC HEALTH THREATS BEFORE THEY ARE CONFIRMED BY LABORATORY TESTS.  COMMUNITY-BASED SURVEILLANCE INVOLVES THE ACTIVE PARTICIPATION OF COMMUNITIES IN MONITORING AND REPORTING HEALTH EVENTS. COMMUNITY MEMBERS ARE TRAINED TO RECOGNIZE AND REPORT CASES OF DISEASES OR OTHER HEALTH EVENTS. KEY FEATURES: ENGAGEMENT: ACTIVELY INVOLVES THE COMMUNITY, WHICH CAN LEAD TO INCREASED AWARENESS AND QUICKER REPORTING OF HEALTH EVENTS. TIMELINESS: CAN BE PARTICULARLY EFFECTIVE IN DETECTING OUTBREAKS IN REMOTE OR UNDERSERVED AREAS WHERE FORMAL HEALTHCARE INFRASTRUCTURE IS  INTEGRATED SURVEILLANCE INTEGRATED SURVEILLANCE COMBINES DATA FROM MULTIPLE SOURCES, INCLUDING PASSIVE, ACTIVE, SENTINEL, SYNDROMIC, AND LABORATORY-BASED SURVEILLANCE, TO PROVIDE A MORE COMPREHENSIVE VIEW OF PUBLIC HEALTH. ADVANTAGES:- COMPREHENSIVE DATA: PROVIDES A MORE COMPLETE PICTURE BY INTEGRATING DIFFERENT TYPES OF DATA AND SURVEILLANCE SYSTEMS. COORDINATION: REQUIRES COORDINATION BETWEEN VARIOUS SURVEILLANCE SYSTEMS AND DATA SOURCES, WHICH CAN BE CHALLENGING. ALLOWS FOR MORE SOPHISTICATED ANALYSIS OF TRENDS AND PATTERNS ACROSS DIFFERENT DATA (ENHANCED ANALYSIS)  EXAMINE SCREENING TESTS REGARDING THEIR VALIDITY RELIABILITY AND AS A MEASURE TO DETECT DISEASES. DEFINITION –WHAT IS SCREENING? THE PRESUMPTIVE IDENTIFICATION OF UNRECOGNIZED DISEASE OR DEFECTS BY THE APPLICATION OF TESTS, EXAMINATION OR OTHER PROCEDURES THAT CAN BE APPLIED RAPIDLY. DIAGNOSTIC CONFIRMATION IS REQUIRED ( MORE THOROUGH CLINICAL EXAMINATION OR ADDITIONAL TESTS)  SCREENING TEST DEFINED A SCREENING TEST IS A MEDICAL PROCEDURE OR TEST PERFORMED ON INDIVIDUALS WHO ARE ASYMPTOMATIC WITH THE GOAL OF IDENTIFYING THOSE WHO MAY BE AT AN INCREASED RISK OF DEVELOPING A PARTICULAR DISEASE. THE PURPOSE IS TO DETECT THE POTENTIAL PRESENCE OF A HEALTH PROBLEM AT AN EARLY STAGE WHEN IT MAY BE MORE TREATABLE OR MANAGEABLE. NON-DIAGNOSTIC I.E SCREENING TESTS ARE NOT DEFINITIVE; A POSITIVE RESULT USUALLY LEADS TO FURTHER DIAGNOSTIC TESTING TO CONFIRM THE PRESENCE OF THE DISEASE OR CONDITION. THEY FACILITATE EARLY DETECTION: THE TEST AIMS TO IDENTIFY CONDITIONS EARLY TO IMPROVE OUTCOMES, SUCH AS TREATMENT OPTIONS AND SURVIVAL RATES.  VALIDITY AND RELIABILITY OF SCREENING TESTS VALIDITY REFERS TO HOW WELL A SCREENING TEST MEASURES WHAT IT IS INTENDED TO MEASURE. IT IS CRUCIAL IN ENSURING THAT THE TEST IS USEFUL IN IDENTIFYING A CONDITION ACCURATELY. SENSITIVITY: THE ABILITY OF A TEST TO CORRECTLY IDENTIFY THOSE WITH THE DISEASE (TRUE POSITIVES). SPECIFICITY: THE ABILITY OF A TEST TO CORRECTLY IDENTIFY THOSE WITHOUT THE DISEASE (TRUE NEGATIVES).  VALIDITY AND RELIABILITY OF SCREENING TESTS POSITIVE PREDICTIVE VALUE (PPV): THE LIKELIHOOD THAT A PERSON WITH A POSITIVE TEST RESULT ACTUALLY HAS THE DISEASE. A TEST WITH HIGH PPV WILL MEAN MOST POSITIVE RESULTS TRULY REFLECT DISEASE PRESENCE. NEGATIVE PREDICTIVE VALUE (NPV): THE LIKELIHOOD THAT A PERSON WITH A NEGATIVE TEST RESULT TRULY DOES NOT HAVE THE DISEASE. HIGH NPV MEANS NEGATIVE RESULTS ARE TRUSTWORTHY FOR RULING OUT THE DISEASE. SEE HANDOUT  VALIDITY AND RELIABILITY OF SCREENING TESTS RELIABILITY REFERS TO THE CONSISTENCY OF THE TEST RESULTS WHEN REPEATED UNDER SIMILAR CONDITIONS. A RELIABLE TEST PRODUCES THE SAME OR SIMILAR RESULTS UPON REPEATED ADMINISTRATIONS. TEST-RETEST RELIABILITY: IF THE SCREENING TEST IS REPEATED ON THE SAME PERSON UNDER THE SAME CONDITIONS, THE RESULTS SHOULD BE CONSISTENT. INTER-OBSERVER RELIABILITY: WHEN DIFFERENT HEALTHCARE PROFESSIONALS PERFORM THE TEST, THEY SHOULD OBTAIN THE SAME RESULTS. INTRA-OBSERVER RELIABILITY: THE SAME HEALTHCARE PROVIDER SHOULD OBTAIN THE SAME RESULT WHEN REPEATING THE TEST ON THE SAME PATIENT.  SCREENING PROGRAM IT TARGETS PEOPLE WHO MAY APPEAR HEALTHY OR ASYMPTOMATIC. SCREENING PROGRAMS ARE SYSTEMATIC, ORGANIZED EFFORTS TO IDENTIFY INDIVIDUALS IN A POPULATION WHO MAY HAVE A SPECIFIC DISEASE OR CONDITION, OFTEN BEFORE SYMPTOMS APPEAR. THE PRIMARY GOAL OF A SCREENING PROGRAM IS EARLY DETECTION TO IMPROVE HEALTH OUTCOMES BY FACILITATING TIMELY INTERVENTION, TREATMENT, AND MANAGEMENT. THESE PROGRAMS ARE TYPICALLY IMPLEMENTED FOR CONDITIONS WHERE EARLY DIAGNOSIS CAN SIGNIFICANTLY REDUCE MORBIDITY, MORTALITY, AND HEALTHCARE COSTS.  SCREENING PROGRAM KEY FEATURES OF SCREENING PROGRAMS TARGET POPULATION: SCREENING PROGRAMS ARE DESIGNED FOR POPULATIONS AT RISK FOR A SPECIFIC DISEASE. THE TARGET GROUP MAY VARY BASED ON AGE, GENDER, LIFESTYLE, OR GENETIC FACTORS. EXAMPLE: WOMEN AGED 40 AND ABOVE, ARE THE TARGET FOR BREAST CANCER SCREENING PROGRAMS USING MAMMOGRAPHY.  SCREENING PROGRAM SYSTEMATIC APPROACH: SCREENING PROGRAMS FOLLOW STRUCTURED PROTOCOLS FOR IDENTIFYING ELIGIBLE INDIVIDUALS, PERFORMING THE SCREENING TESTS, AND FOLLOWING UP WITH APPROPRIATE DIAGNOSTIC TESTS OR TREATMENTS. CRITERIA FOR SCREENING PROGRAMS: A SCREENING PROGRAM SHOULD MEET SPECIFIC CRITERIA TO ENSURE ITS EFFECTIVENESS AND SAFETY: SIGNIFICANT PUBLIC HEALTH PROBLEM: THE CONDITION SHOULD BE IMPORTANT AND PREVALENT ENOUGH TO JUSTIFY WIDESPREAD SCREENING..  SCREENING PROGRAM CONT’D EARLY DETECTION BENEFITS: THERE SHOULD BE A BENEFIT FROM DETECTING THE DISEASE EARLY (E.G., BETTER TREATMENT OUTCOMES, REDUCED MORTALITY).ACCURATE AND RELIABLE TEST: THE SCREENING TEST USED MUST BE VALID (SENSITIVE AND SPECIFIC) AND RELIABLE. COST-EFFECTIVENESS: THE PROGRAM SHOULD PROVIDE A FAVORABLE BALANCE BETWEEN COST AND BENEFITS TO THE HEALTHCARE SYSTEM AND THE POPULATION SOURCES OF INFORMATION FOR DISEASE SURVEILLANCE/EPIDEMIOLOGY CENSUS, VITAL STATISTICS, MORBIDITY DATA, MORTALITY DATA, NOTIFIABLE DISEASES REPORTS, HOSPITAL RECORDS, PRIVATE PHYSICIANS’ OFFICES, DISEASE REGISTERS, COMMUNITY, RESEARCH AND SURVEY FINDINGS, OTHER.  SOURCES OF INFORMATION FOR DISEASE SURVEILLANCE/EPIDEMIOLOGY CENSUS - A SYSTEMATIC COLLECTION OF DEMOGRAPHIC INFORMATION ON A POPULATION, TYPICALLY CONDUCTED BY GOVERNMENTS AT REGULAR INTERVALS (E.G., EVERY 10 YEARS). RELEVANCE TO DISEASE SURVEILLANCE: PROVIDES BASELINE POPULATION DATA, SUCH AS AGE, SEX, SOCIOECONOMIC STATUS, AND GEOGRAPHIC DISTRIBUTION, WHICH ARE ESSENTIAL FOR CALCULATING DISEASE RATES, IDENTIFYING AT-RISK POPULATIONS, AND PLANNING PUBLIC HEALTH INTERVENTIONS  SOURCES OF INFORMATION FOR DISEASE SURVEILLANCE/EPIDEMIOLOGY VITAL STATISTICS DATA RELATED TO VITAL EVENTS IN A POPULATION, SUCH AS BIRTHS, DEATHS, MARRIAGES, AND DIVORCES, OFTEN COLLECTED BY GOVERNMENT AGENCIES. RELEVANCE TO DISEASE SURVEILLANCE: DEATH AND BIRTH RECORDS ARE CRUCIAL FOR TRACKING MORTALITY RATES, FERTILITY RATES, AND LIFE EXPECTANCY, HELPING IDENTIFY TRENDS IN DISEASE-RELATED DEATHS (E.G., MATERNAL MORTALITY, INFANT MORTALITY).  SOURCES OF INFORMATION FOR DISEASE SURVEILLANCE/EPIDEMIOLOGY MORBIDITY DATA - INFORMATION ON THE INCIDENCE AND PREVALENCE OF DISEASES OR HEALTH CONDITIONS WITHIN A POPULATION. MORTALITY DATA - INFORMATION ON THE NUMBER AND CAUSES OF DEATHS WITHIN A POPULATION, OFTEN COLLECTED FROM DEATH CERTIFICATES. NOTIFIABLE DISEASE REPORTS - REPORTS OF DISEASES THAT ARE LEGALLY REQUIRED TO BE REPORTED TO PUBLIC HEALTH AUTHORITIES BY HEALTHCARE PROVIDERS, LABORATORIES, OR OTHER ENTITIES. (E.G., TUBERCULOSIS, MEASLES, COVID-19 ( LINE LISTING OR REPORTING FORM)  SOURCES OF INFORMATION FOR DISEASE SURVEILLANCE/EPIDEMIOLOGY HOSPITAL RECORDS - MEDICAL RECORDS MAINTAINED BY HOSPITALS THAT CONTAIN INFORMATION ABOUT PATIENT DIAGNOSES, TREATMENTS, OUTCOMES, AND HOSPITALIZATIONS. (HOSPITAL ACTIVE SURVEILLANCE)  SOURCES OF INFORMATION FOR DISEASE SURVEILLANCE/EPIDEMIOLOGY PRIVATE PHYSICIANS’ OFFICES - MEDICAL RECORDS FROM PRIVATE PRACTICE PHYSICIANS WHO PROVIDE OUTPATIENT CARE TO INDIVIDUALS. DISEASE REGISTERS - DATABASES THAT SYSTEMATICALLY COLLECT INFORMATION ON INDIVIDUALS WITH SPECIFIC DISEASES, USUALLY CHRONIC OR RARE CONDITIONS (E.G., CANCER REGISTRIES, DIABETES REGISTRIES.  SOURCES OF INFORMATION FOR DISEASE SURVEILLANCE/EPIDEMIOLOGY COMMUNITY - INFORMATION COLLECTED FROM COMMUNITY HEALTH PROGRAMS, COMMUNITY HEALTH WORKERS, OR THROUGH DIRECT ENGAGEMENT WITH THE POPULATION. RELEVANCE TO DISEASE SURVEILLANCE: CAPTURES HEALTH DATA FROM UNDERSERVED OR HARD-TO-REACH POPULATIONS, INCLUDING DISEASE SYMPTOMS, HEALTH BEHAVIORS, AND LOCAL HEALTH CONCERNS THAT MAY NOT BE RECORDED IN FORMAL HEALTHCARE SETTINGS.  SOURCES OF INFORMATION FOR DISEASE SURVEILLANCE/EPIDEMIOLOGY RESEARCH AND SURVEY FINDING - DATA GENERATED FROM EPIDEMIOLOGICAL STUDIES, CLINICAL TRIALS, AND HEALTH SURVEYS CONDUCTED BY RESEARCHERS OR PUBLIC HEALTH ORGANIZATIONS. RELEVANCE TO DISEASE SURVEILLANCE: PROVIDES DETAILED, OFTEN POPULATION-SPECIFIC, DATA ON HEALTH BEHAVIORS, RISK FACTORS, DISEASE PREVALENCE, AND HEALTHCARE ACCESS, HELPING TO IDENTIFY EMERGING TRENDS AND REFINE PUBLIC HEALTH STRATEGIES. INTERPRETING KEY COMPONENTS OF EPIDEMIOLOGIC DATA WHAT, WHO, WHERE, WHEN, HOW, WHY RISK FACTORS DEFINITION: VARIABLES THAT INCREASE THE LIKELIHOOD OF DEVELOPING A DISEASE OR CONDITION. THESE CAN BE BEHAVIORAL, ENVIRONMENTAL, GENETIC, OR SOCIAL. INTERPRETATION: IDENTIFYING AND UNDERSTANDING RISK FACTORS HELPS IN TARGETING PREVENTION AND INTERVENTION STRATEGIES. FOR EXAMPLE, SMOKING IS A KNOWN RISK FACTOR FOR LUNG CANCER, AND ADDRESSING SMOKING CAN HELP REDUCE LUNG CANCER RATES.  THE END SEE EPIDEMIOLOGY MEASUREMENTS AND CALCULATIONS POWER POINT PRESENTATION