n Fraction calculated from numerator divided by denominator

สดสวนคออะไร ? n Fraction calculated from numerator divided by denominator (which contains numerator) n Example: n In this room has 164 member, of which 68 are female and 96 are male. n Fraction female? n 68 / (68+96) = 0. 415

อตรา คออะไร ? n. Number of events (numerator) divided by the population time or person-time (denominators). n Example: n 400 new TB cases occur in a community of 25, 000 people over a period of 2. 5 years n How many of TB incidence rate?

rate? n 400 new TB cases occur in a community of 25, 000 people over a period of 2. 5 years n 400/ (25, 000 x 2. 5) = 0. 0064 person-year n or 6. 4 cases per 1, 000 person-years observation n or 640 cases per 100, 000 person-years observation

อตราสวนคออะไร ? n Result of division of one number (numerator) by another number (denominator) ( which dose not usually contain numerator) n Example: n In this room has 164 member, of which 68 are female and 96 are male. n Female-to-male ratio? Male-to-female ratio? n 68 / 96 = 0. 708 or 96 / 68 = 1. 412

☺ What is formula of mean? n Mean = x = ∑ xi n n This formula is read as “x-bar equals the sum of the x’s divided by n. ” n Example …. . next ⇛ ⇛ ⇛

In this example we will demonstrate how to calculate the mean incubation period for the hepatitis outbreak. n In an outbreak of hepatitis A, 6 persons became ill with clinical symptoms 24 to 31 days after exposure. n The incubation periods for the affected persons (xi) were 29, 31, 24, 29, 30, and 25 days. x = 29 + 31 + 24 + 29 + 30 + 25 = 168 n n=6 n Mean = 168 / 6 = 28. 0 days n ∑ i

What is geometric mean? n n n The geometric mean is …. the mean or average of a set of data measured on a logarithmic scale. calculated as the nth root of the product of n observations. used when the logarithms of the observations are distributed normally rather than the observations themselves. This situation is typical in dilution assays, such as serum antibodies described above, and in environmental sampling data.

What is formula of geometric mean? x 1 x X 2 x X 3 x… Xn n Geometric mean = geo x = n In practice, the geometric mean is calculated as: n = antilog ( 1/n ∑ Log Xi )

The variance and standard deviation are measures of the deviation or dispersion of observations around the mean of a distribution. Variance is the mean of the squared differences of the observations from the mean. . The standard deviation is the square root of the variance. It is usually represented in formulas as s.

����������������. . . n การเลอกและประยกตใชใหเ หมาะสม n Choose and apply the appropriate measure of central location and of dispersion

การวดการปวย (Measures of Morbidity)

�������� � n ������ (Association) n => Positive association => Negative association => No association n Positive association n ===> ������� (Artifactual) ===> ���� (Real) n n n

�������� ��� Positive association Statistical association Non-statistical association Causal association Non-causal association Direct association Indirect causal association

�������� � • ��������� (Strength of association) • ���������� (Consistency of association) • ����� (Specificity of association) • ����� (Time sequence of association) • ������ (Coherence association)

������ (Attributable risk) �������� = �������������� ����� • Absolute exposure attributable risk • Population attributable risk (PAR) PAR = Pe (R-1) x 100 % 1 + Pe (R-1)

���������� (Descriptive Epidemiology) ���������� ��� � ������������ ����� (Retrospective descriptive study) (Prospective descriptive study) ���������� (Cross-sectional descriptive study)

Design of a case-control study TIME Direction f inquiry Exposed Not exposed Cases (people with disease) Population Exposed Not Exposed Controls (people without disease)

Design of cohort study TIME Direction of inquiry disease Population People without the disease Exposed No disease Not exposed disease No disease

������� ���. 1 Common-Source epidemics : ������� 2. Propagated-Source epidemics: �������

Lung Liver Colon Bladder Oral cavity Oesophagus Stomach NPC Rectum Larynx Liver Lung Colon Stomach Skin Leukaemia Oral Cavity Nasopharynx Bladder Lymphoma ������ �� ������� Lung Liver Stomach Bladder Larynx Skin Oral cavity Prostate Lymphoma Colon ASR per 100, 000 Lung Liver Oesophagus Oral cavity Colon Larynx Prostate Skin Nasopharynx Larynx ������ � ������������� 10 ������������� (

Cervix Breast Lung Colon Ovary Oral Cavity Corpus Uteri Liver Leukaemia Thyroid ������ �� Lung Cervix Breast Liver Stomach Oral Cavity Ovary Leukaemia Skin Colon ������� �� ASR per 100, 000 Liver Cervix Breast Oral Cavity Ovary Thyroid Skin Lung Colon Leukaemia ������ � Cervix Breast Oral Cavity Lung Thyroid Skin Leukaemoa Ovary Oesophagus Colon ��������������� 10 ��������������� (���� )

Female Male Thailand, Khon. Kaen China, Qidong Mali, Bamako Japan, Osaka Japan, Hiroshima Japan, Saga Thailand (Est. ) Hong Kong Zimbabwe, Harare African: Japan, Nagasaki China, Shanghai Korea, Kangwha Philippines, Manila US, Los Angles : Korean China, Tianjin Singapore : Chinese US, San Francisco Chinese: Vietnam, Hanoi Thailand, Chiang Mai Thailand, Songkhla Thailand, Khon Kaen Zimbabwe, African Harare : China, Qidong Mali, Bamako Thailand (Est. ) Japan, Osaka Japan, Hiroshima Japan, Saga China, Shanghai Thailand, Chiang Mai Hong Kong China, Tianjin Japan, Nagasaki Philippines, Manila Korea, Kangwha US, San Francisco : Chuinese Peru, Trujillo Singapore : Chinese US, Los Angles : Korean Thailand, Songkhla ASR (World) ��������� �

Thank you for your attention