รวมเล่ม_PowerPoint_ว.ระบาดวิทยาฯ 2565 (Wanpen)

The distribution of a disease 2 in a population

✓ Time ✓ Place ✓ Certain individual characteristics of the people Picture from https://www.facebook.com/Phonics1st/photos/a.281604888539275/1988561864510227/

➢ The distribution by various geographic areas ➢ The frequency of the disease distribution by age, sex, race, socioeconomic class, and individual living habits (such as smoking, alcohol consumption, etc.)

1 Epidemiologic triad The nature of a disease in a 2 population (man)

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The contents of this chapter Web of causation of disease The occurrence of non-communicable diseases/ chronic diseases

Web of causation of disease ➢ Causation of disease: any disease is not caused by only one factor. Agent •ปัจจยั กอ่ โรค Host •มนษุ ย์ Environme •สงิ่ แวดลอ้ ม nt

Epidemiologic triad (ปัจจยั สามทางวทิ ยาการระบาด) Agent • ปัจจยั ก่อโรค Host • มนษุ ย์ Environment • ส่งิ แวดลอ้ ม

Web of causation of disease ➢ The concept of disease etiology is a \"web of causation\" which includes all the predisposing factors of any type and their complex relations with each other and with the disease. สาเหตุ cause10 cause1 cause2 cause3 cause9 Outcome/disease cause4 cause11 cause8 cause6 cause5 cause11 cause7

Web of causation of disease Source: Friedman, D. G. (1974). Primer of Epidemiology. USA: A Blakiston publication. P.4..

The occurrence of non-communicable diseases OR chronic diseases

Non-communicable disease/Chronic diseases Definition of non-communicable disease NCD medical condition ➢ Cardiovascular diseases cannot be passed (like heart attacks and from person to person stroke), ➢ Cancer, chronic diseases ➢ Chronic respiratory diseases long duration and slow (such as chronic obstructed progression pulmonary disease and asthma) and ➢ Diabetes ➢ Hypertension ➢ etc

The occurrence of non-communicable diseases/Chronic diseases

✓ Genetics ✓ Age 1. Non-modification ✓ Gender

2. Modification ❖ Tobacco consumption ❖ Drinking alcohol ❖ Improper food intake ❖ Inadequate physical ❖ Air pollution

❑ Hyperlipidemia ❑ High blood pressure ❑ High blood sugar ❑ Overweight / Obesity

➢ Globalization ➢ Urbanization ➢ Elderly society

The occurrence of non-communicable diseases/Chronic diseases ✓ Genetics ❖ Tobacco consumption ✓ Age ❖ Drinking alcohol ✓ Gender ❖ Improper food intake ❑ Hyperlipidemia ❑ High blood pressure ❖ Inadequate physical ❑ High blood sugar ❖ Air pollution ❑ Overweight / Obesity ➢ Globalization ➢ Elderly society ➢ Urbanization

Risk Factors of Disease: BEINGS Model The ➢“B”—BIOLOGIC AND BEHAVIORAL FACTORS acronym ➢“E”—ENVIRONMENTAL FACTORS BEINGS can ➢“I”—IMMUNOLOGIC FACTORS such as chemotherapy serve as a mnemonic of cancer and the long-term use of corticosteroids device for the major produce immunodeficiency categories ➢“N”—NUTRITIONAL FACTORS of risk ➢“G”—GENETIC FACTORS factors for ➢“S”—SERVICES, SOCIAL FACTORS, AND SPIRITUAL disease FACTORS From: Joann Elmore, Dorothea Wild, Heidi Nelson, David Katz. (2020). Jekel's Epidemiology, Biostatistics, Preventive Medicine, and Public Health. 5th Edition. Philadelphia: Saunders, p5-7.

Natural History of NCD in Man Prepathogenesis Pathogenesis Period Period Recovery No-disease period Chronic state Disability Defect Death Factors that produce Interaction Host reaction disease stimulation of host stimulation Source: Department of Epidemiology, Faculty of Public Health, Mahidol University, (2012). Learning Module PHEP 602 Principles of Epidemiology. Volume 1, p2-8.

Web of causation of disease The occurrence of non-communicable diseases/ chronic diseases

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The contents of this chapter 1 Overview of biostatistics 2 The epidemiological measurements 2.1 Measures of disease frequency



What are statistics and biostatistics? ❖ Statistics is the ❖Biostatistics is the practice or science of application of statistical collecting and analyzing techniques to scientific numerical data in large research in health- quantities, especially for related fields, including the purpose of inferring medicine, biology, and proportions in a whole public health, and the from those in a development of new representative sample. tools to study these areas.

Biostatistics ▪ Biostatistics deals with the study and methods of collection, presentation, analysis, and interpretation of data for biological research. ▪ Biostatistics is considered one of the foundational disciplines in public health. ▪ Biostatisticians conduct quantitative and qualitative research to help identify population health trends and risk factors.

Types of biostatistics Descriptive พรรณนา Two types of biostatistics อา้ งองิ statistics Inferential statistics have two main Descriptive statistics uses: summarize and organize the characteristics of a data set. 1. Making estimates about populations A data set is a collection of 2. Testing hypotheses to draw conclusions responses or observations from a sample or entire about populations population (ประชากรทงั้ หมด). ✓ Hypothesis tests ✓ Confidence intervals

Inferential Inferential statistics help you to make predictions (“inferences”) Statistics from that data. With inferential statistics, you take data from samples and make generalizations about a population. Source: https://www.pinterest.com/pin/326299935485508303/

Types of data Qualitative or Quantitative or ✓ Pulse Categorical data Numeric data ✓ Weight ✓ Length Normal scale Ordinal or ✓ Temperature Ranking scale ✓ pH Ratio scale ✓ SAT score Interval scale ✓ Gender ✓ Socio-economic status (“low”,” middle”,” high”) ✓ Home town ✓ Education level (“high school”,” BS”,”MS”,” Ph.D.”)

Statistical Process There are four steps of the statistical process: 1. data collection, 2. data analysis, 3. data presentation, and 4. interpretation.

data analysis Two types of biostatistics อา้ งองิ ➢ Mean (ค่าเฉล่ยี ) ➢ Median (มธั ยฐาน) ➢ Mode (ฐานนิยม) Descriptive พรรณนา statistics ➢ Standard deviation ➢ Range (พสิ ยั ) ➢ Variance (ความแปรปรวน)

Source: HYPERTENSION CARE IN THAILAND - WHO | World Health ...https://apps.who.int

Source: HYPERTENSION CARE IN THAILAND - WHO | World Health ...https://apps.who.int

1.2



Types of epidemiological measurements 1. Measures of disease frequency EP.1 2. Measures of association EP.2 3. Measures of potential impact EP.2

Basic tools for epidemiological measurements 1. Count 2. Ratio 3. Proportion or number or (อัตราสว่ น) Proportional frequency Rate (สัดส่วน) 6. Risk Ratio, or 5. Index (ดชั นี) 4. Rate (อัตรา) Relative Risk, Odd Ratio (ความเสีย่ งสัมพัทธ์) * สพุ รรณี ธรากลุ , 2562; วิฑรู ย์ โลห่ ์สนุ ทร, 2561; Jekel, Katz, Elmore, & Wild, 2007

Basic tools for epidemiological measurements 1. Count number or Counting the number of actual events in the population frequency of interest or have some characteristics in common at a given area and during the study period. 2. Ratio (อตั ราส่วน) The relationship between two groups or amounts expresses how 3. Proportion or Proportional much bigger one is than the other Rate (สดั ส่วน) The ratio formula for any two quantities say a and b is given as, a : b = a / b. Since a and b are individual amounts for two quantities, the total quantity combined is given as (a + b) Proportion, in general, is referred to as a part, share, or number considered in comparative relation to a whole, (total value) Proportion = ������ or Proportion a+b+c+ …������……..(total×) 100 = a+b+c+ ………..(total)

Basic tools for epidemiological measurements 4. Rate Rate = ������ x ������ (อัตรา) ������+������ ������ = Numerator (เลขตวั ตง้ั ) ������ + ������ = Denominator (เลขตัวหาร) The value of ������ (constant) can be 100, 1,000, 10,000, 100,000.

Basic tools for epidemiological measurements 5. Index is an approximate value of the rate (ดัชน)ี ➢It is often used only when the true denominator cannot be found. ➢The value of something else that is relevant must be used instead. ❑ Maternal death rate = 0.08/100 live births/year ❑ Death rate = 5.16/1,000 population/year

6. Relative RReislkaotirveRisRkisRkat(iคoา่ (คRวRา)มOเสdีย่dงRสaัมtพioทั (ธค)์่าความเส่ยี งสัมพทั ธ)์ Relative Risk (RR) A relative risk (RR), also called risk ratio, compares the risk of a health event (disease, injury, risk factor, or death) among one group with the risk among another group. The formula for RR is: Relative Risk (RR) = ������������������������ ������������ ������������������������������������������ (������������������������������������������������������ ������������������������������������������������������������,������������������������������������ ������������������������) ������������ ������������������������������ ������������ ������������������������������������������ (������������������������������������������ ������������������������������������������������) ������������������������ ������������ ������������������������������������������ (������������������������������������������������������ ������������������������������������������������������������,������������������������������������ ������������������������) ������������ ������������������������������ ������������ ������������������������������������������������������ (������������������������������������������������������������ ������������������������������)



Measurement of disease frequency (Measure of morbidity..การป่วย..) 1. Prevalence rate 2. Incidence rate (อัตราความชุก) (อตั ราอบุ ตั กิ ารณ)์ is the proportion of persons in a • Incidence rate XK population who have a particular disease or attribute at =• =ปรจะาชนาวกนรขทองั้ งหผมปู้ ด่วทย่ีเใสห่ียมงท่ต่ีเอ่ กกิขานึ้ รใเนปร็นะโยรคะเใวนลราะทย่ีทะเาวกลาารเศดกึยี ษวกานั × ������ a specified point in time or over a specified period of time. • Incidence refers to the occurrence of new cases of disease or injury in a = XK population over a specified period of time. The value of ������ (constant) can be 100, 1000, 10,000

❖ Point prevalence is a ❖Period prevalence is measure of the the number of proportion of people in a individuals identified population who have a as cases during a disease or condition at a specified period of particular time, such as time, divided by the a particular month or total number of date. It is like a snapshot people in that of the disease in time. population.

Prevalence Rate 1. Point prevalence 2. Period prevalence ➢ Point prevalence measures • Prevalence is a useful the proportion of existing measure to quantify the people with a disease in a burden of disease in a defined population at a population at a given point in single point in time. time. = XK The value of ������ (constant) can be 100, 1000, 10,000

Incidence Rate 1. Cumulative • = จานวนผทู้ ่ีเร่มิ ป่ วยในชว่ งระยะเวลาท่ีทาการศกึ ษา Incidence (CI): จานวนประชากรเม่ือเรม่ิ ตน้ การศกึ ษา∗ 2. Incidence Density (ID) • Incidence Density (ID) = จานวน จานวนผทู้ ่ีเร่มิ ป่วยในระยะเวลาท่ีทาการศกึ ษา × ������ or Person-time Incidence person−time at risk∗ ตลอดระยะเวลาท่ีทาการศกึ ษา * personS-timuemat risko=fผลtรวhมขeองระpยะeเวลrาsทส่ี oงั เกnต (-หtรือiรmะยะเeวลาทoี่สมัfผสั tปัจhจยั eเสยี่ aง) ขtอ-งผrู้ถiกู sสงั kเกตแตล่ ะราย population (Person-time at risk)

Source: Incidence Rate https://www.cdc.gov/c sels/dsepd/ss1978/les 3.1 Primary Attack Rate son3/section2.html 3. Attack Rate ( ัอตราโจมจับ) จานวนผู้ป่วยรายแรก ๆ (∗) ที่เกดิ ข้ึนในช่วงเวลาท่ีศกึ ษา × 100 = = จานวนประชากรทเ่ี สี่ยงในระยะเวลาเดียวกัน (*) หมายถงึ ผปู้ ว่ ยรายแรกทีพ่ บและนาโรคเขา้ มาในครอบครัวหรือชมุ ชน 3.2 Secondary Attack Rate แล้วเกิดการปว่ ยขึน้ ภายในช่วงระยะฟักตวั ของโรค∗ * จานวนผู้ท่ีมีภมู ไิ วรับท่ีสัมผสั กับผู้ป่วยรายแรก∗∗ == × 100 ** * กลมุ่ ผูป้ ่วยที่อาจไดร้ บั เชื้อจากกล่มุ ผูป้ ่วยปฐมภมู ิ ** ไมน่ ับผปู้ ่วยรายแรก (หรอื ชดุ แรก) และรายทม่ี ีภมู ติ า้ นทาน

3. Attack Rate Primary attack rate