1 introduction to biostatistics

data
research literature
popular media

____ utilized and summarized frequently in ? ?

bad data

can be analyzed and summarized to provide incorrect or harmful of non-informative informative

statistics

science dealing with the collection, organization, analysis, and interpretation of data

public health statistics

refer to quantitative data needed as basis for planning, monitoring, and evaluation of health services

vital statistics

data on vital events (births, deaths, marriage)

health statistics

morbidity, hospital and clinical statistics, service statistics

morbidity

cause and frequency of illness

hospital and clinical statistics

no. of admissions and discharges, bed occupancy, length of stay

service statistics

no. of baby immunized, no. household with sanity toilet, no. of women practicing family planning

biostatistics

scientific discipline focused with the application of statistical principles concerning biological problems

• public health

• medical sciences

• agriculture

• environmental

• ecological sciences

data reduction
objective appraisal and evaluation
decision making
design and analyze research well

biostatistics can be useful in terms of being a:

assessment of the health status in the community
determination of disease causation
prevention and control of disease
monitoring and evaluation of health interventions
provision of health policy formulation and health care planning

role of biostatistics in public health

descriptive
inferential

major branches of statistics

descriptive

summarize and present data

• measures of central tendency

• measures of dispersion and location

• tabular presentation

• graphical presentation

inferential

predictions, generalizations, and conclusions

• estimation of parameters

• hypothesis testing

estimation

process by which a statistics computed from a random sample is used to approximate or estimate the corresponding parameter

estimation

generation of point or interval estimates

hypothesis testing

set of procedure that culminates in the rejection or non-rejection of the null hypothesis based on probability of occurrence of the sample results if the null hypothesis were true

expressed numerically
treated as a group of observations
subject to variation

statistical data must have the following characteristics

variability

tendency of a measurable characteristic or behavior to change

variable

measurement of characteristics of interest

constant

phenomenon whose value remains the same from person to person, from time to time, or from place to place

• pull of gravity

• speed of light

qualitative
quantitative

types of variables

qualitative

non-quantifiable categories

qualitative

numerical representation as labels or codes only

• sex

• education level

• disease status

• eyecolor

quantitative

values indicate quantity or amount

quantitative

either discrete or continuous

discrete variables

assume only integral or whole numbers

continuous variables

attain any value including fractions and decimals

nominal
ordinal
interval
ratio

levels of measurement

nominal

classificatory scale used only as labels

nominal

represent a set of mutually exclusive and exhaustive classes

ordinal

classes can be orders or ranked

interval

distances between all adjacent classes are equal

interval

does not have a true zero point (arbitrary)

ratio

meaningful zero point exists

ratio

ratio of two values can be meaningfully computed and interpreted