Lab Module 1-4 Flashcards
branch of applied statistics directed toward application in health sciences and biology.
Biostatistics
the study of diseases in population
Epidemiology
refers to the science dealing w/ the collection, organization,
analysis and interpretation of
numerical data
Statistics
refers to the
application of statistical methods to
the life sciences like biology, medicine
and public health.
Biostatistics
set of data or a
mass of observations, like public health
statistics - plural sense
the body of
methods or techniques for the organization &
analysis of collected information
statistics - singular sense
data on vital events as to the
number of birth, death &
marriages.
- bookkeeping of humanity.
Vital statistics
3 Important Uses of Vital Statistics
- legal use
- source material
- health units
in claiming life insurance upon the
death of the benefactor
death registration
6 Special Uses of Vital Statistics
- accidents
- suicides
- communicable disease control
- maternal and infant mortality
- occupational statistics
- value of periodic medical exam
– logbook where data are written.
- it contains data of birth & death
registration for mortality & natality statistics.
Source Material
– refer to the health workers who take
part in the administration of gov’t health
programs.
Health Units
it keeps information pertains to health.
Health Statistics
The Application of Health Statistics to
Public Health Data are as follows:
- nutrition
- sanitation
- industrial hygiene
- dentistry
- laboratory
- epidemiology
- maternal child hygiene
uses different methods of
statistics to summarize and present data in
narrative form.
Descriptive statistics
methods of tabulation
- graphical presentation
- computation of averages
- measures of variability
uses generalizations & conclusions
about a target population w/c is based on
results from a sample
Inferential Statistics
- experimental method
tendency of
measurable characteristics to change from
one individual or setting w/in the same
individual or setting.
Phenomena of Variation
i.e. person’s blood pressure
values remain the same from time to
time.
Constant
i.e. – minutes in an hour
- number of days a week
measured
according to quantity or values and are
expressed numerically.
Independent/dependent variable
i.e. – birthweight
- hospital bed capacity
- arm circumference
- population size
variables w/c can
assume only integral values or whole number
discrete variable
i.e. - books
variables w/c can
attain values in terms of fraction or decimals.
continuous variables
i.e. – birthweight
- arm circumference
numbers or symbols used to classify
an object, person or characteristics into
categories.
Nominal
i.e. – collection of yes, no, undecided
responses to a medical survey question
data are arranged in some order but
differences between data values cannot
be determined.
Ordinal
i.e. – size of T-shirt
- socio economic status
- in 10 urine samples 6 were rated normal, 4
pathological
characterized by a common and
constant unit and measurement.
- the distances between any two
numbers on the scale are known
sizes.
Interval
i.e. - temp. reading of 15ºC and 35ºC
has a true zero point wherein the
number zero indicates the absence of the
characteristics under considerations.
Ratio
i.e. – height in meters
- weight in kilograms
CENTRO ESCOLAR UNIVERSITY 13
obtained first hand by the
investigator from first hand sources.
Primary data
i.e. – thesis & dissertations
- interview and questionnaire
- letters, diaries and autobiographies
- experimentation
- journals and newspapers
are finished products taken from
raw materials.
- data w/c are already existing.
Secondary data
i.e. – data obtained from registry of cases of
hospitals
- documented materials
- book of factual information i.e. textbooks
oral type of
questionnaire w/ a face to face contact
bet. the researcher and the respondents.
Direct or Interview method
requires an appointment w/ the
respondents
Formal
by chance interview
Informal
involves a patient & his health provider
Clinical
wider & deeper coverage as in
investigative or detective cases.
In-depth
solicits views and opinions from a group of
people
Focus
interviewed person has given the
task of providing pieces of advice.
Non- Directed
i.e. – counselling given by guidance counsellor
set of written & planned
questions related to a particular topic intended to answer the problem of the study
Indirect or Questionnaire
answerable through options
or choices
Close ended
questions that require further
explanation in phrases or paragraphs.
Open ended
i.e. narrative responses
data obtained through births, deaths,
marriages, licenses and census.
Registration
used by scientific researches.
Experimental
the act of studying only a portion of the
population to represent the whole.
Sampling
i.e. diagnosing a patient based on his blood count
a sampling procedure
wherein the probability of each element being
included in the sample is unknown.
- as a result there is no way of assessing the
reliability of the sample results.
Non probability sample
any sampling procedure wherein
each element in the population has a known probability
of being included in the sample.
Probability sample
a representative
sample of the population is selected based on
an expert’s subjective judgment or on some
pre-specified criteria.
Judgment or Purposive sampling
i.e. an area is selected bec. the community leaders
are known to the investigators.
if the researcher
used in his study whatever items come at hand or
whoever is available
Accidental or Haphazard sampling
i.e. he may interview the first 50 people who enters a
department store or he may ask for volunteers.
collection of data continues
until the pre-specified quota is met.
Quota sampling
i.e. house to house interview
used in confidential researches
wherein the other respondents are picked out by
the previous respondent.
- frequently used when studying “ hidden
population” like drug users & prostitutes, w/ HIV
positive individual.
Snowball technique
there is an equal
chance for every member of the population
of being included in the sample
Simple random sampling
draw lots
method.
fish bowl technique or lottery method
i.e. rolling pieces of paper w/ the names of the
population & have it selected by draw lots
done when the
population is large
table of random numbers
i.e. w/ eyes closed using a pencil pinpoint at any
location a number in the table by chance.
a technique for
selecting members of a sample by picking out
every Kth of the population.
Systematic probability sampling
systematic probability sampling formula
K= N/n where:
K = ratio of the population
N = total population
n = sample population
a pop. w/c is
composed of several strata or subgroups.
Stratified random sampling
samples per group or strata
i.e. – department store, location, industry type
stratified random sampling w/ equal allocation
samples per group depends on the pop.
per group.
i.e. – the bigger the pop., the more the samples;
the smaller the pop., the smaller the
sample.
Stratified random sampling with proportional
allocation
pop. w/c is divided into separate group of
elements called clusters.
i.e. – area sampling such as 5 city blocks, a
clusters or group of students.
Cluster
Sloven’s Formula
n = N/1+Ne^2
where: either 0.05 or o.01 (values chosen to be
consistent w/ the level of significance used
in the tests of hypothesis)
paragraph form
Narrative or Textual
in graph
i.e. bar graph, histogram, pie graph, line
diagram
Graphical
data w/c include lots of figures &
makes use of a statistical table.
Tabular
the sum of all the cases divided by the
number of cases.
Mean
the middle most score in a distribution.
Median
the midpoint of the interval containing
the largest number of cases.
Mode
the
exact values of the observations are
retained.
Ungrouped data or Raw or Scattered
they are cast in a frequency
distribution
Grouped data
Median formula
Md = N+1/2
tabular
arrangement of data into classes or
categories together w/ their corresponding
class frequency.
Frequency distribution table
often called the average, of a numerical set of
data, is simply the sum of the data values divided by the
number of values
Mean
the number that falls in the middle position
once the data has been organized. Organized data means the
numbers are arranged from smallest to largest or from largest to
smallest.
Median
set of data is simply the value that
appears most frequently in the set.
Mode
Data consists of values that can be placed into nonnumeric categories
Qualitative
i.e subjects in college, education level
Data consists of values representing counts or measurements can be measured by tool or scale or count
Quantitative
i.e. grades in biostats, number of students, temperature
No natural ranking or ordering of the data exists
Nominal level (by name)
Can’t get a precise mathematical difference between
levels. ( Could be coded mathematically)
Ordinal level (by order)
can take on any value in an
interval but could also have decimals
(weight, home value, height and 2.45) while
discrete can take on only particular values
(shoe size, number of students and number
of prerequisite courses)
Continuous
Intervals of equal length signify equal differences in the
characteristic.
▪ Differences make sense, but ratios do not.
▪ 100° Fahrenheit is not twice as hot as 50° Fahrenheit.
Occurs when a numerical scale does not have a ‘true zero’ start point
▪ Does 0° Fahrenheit represent an absence of heat?
* Equal interval
Interval ( subtraction level)
EXAMPLES: Temperature, Calendar year and IQ test
At this level, both differences and ratios are meaningful.
* 2 oz glasses of water IS equal to one 4 oz glass of water “ 4oz
of water is twice as much as 2 oz of water.
* Occurs when scale does have a ‘true zero’ start point.
* 0 oz of water is a ‘true zero’ as it is empty, absence of water.
* Ratios involve division (or multiplication) rather than addition
or subtraction
Order
Examples: Mass, Length and Time
is the statistical study of human populations
Demography
the number or body of inhabitants in a place belonging to a specific social,
cultural, socioeconomic, ethnic, or racial subgroup
Population
is a technique used to develop an understanding of the age,
sex, and racial composition of a population and how it has changed over time through
the basic demographic processes of birth, death, and migration.
Demographic Analysis
is broadly defined as the scientific study of
human populations.
Population Studies
Major areas studied include:
-broad population dynamics
- fertility and family dynamics
-health, aging, and mortality
-human capital and labor markets
the absolute number of a population or any demographic event occurring in a specified area in
a specified time period.
Count
the frequency of demographic events in population during a specified time period divided by
the population “at risk” of the event occurring during that time period.
Rate
the relation of one population subgroup to the total population or to another subgroup; that is,
one subgroup divided by another
Ratio
the relation of a population subgroup to the entire population; that is, a population
subgroup divided by the entire population
Proportion
an unchanging, arbitrary number by which rates, ratios, or proportions can be multiplied to
express these measures in a more understandable fashion
Constant
-a statistic that measures events occurring to a COHORT (a group of people sharing a
common demographic experience) who are observed through time.
Cohort measure
a statistic that measures events occurring to all or part of a population during one
period of time.
Period Measure
is the description of a population
according to characteristics such as
age, sex, race or other factors.
Population composition
A population growing at a consistent rate is
expected to form a triangular shape (hence the
name).
population pyramid
are derived from information obtained at the time when the occurrences of
vital events and their characteristics are inscribed in a civil register.
Vital statistics
are the births, deaths, fetal deaths, marriages, and all such events
that have something to do with an individual’s entrance and departure from life
together with the changes in civil status that may occur to a person during his lifetime.
Vital acts and events
Recording of these events in the civil register
vital or civil registration
resulting documents
vital records
are used when these changes cannot be measured directly, as for example health or nutritional
status.
Demographic Indicators
should measure what they are supposed to measure
Valid
the answers should be the same if measured by different people in similar
circumstances
Reliable
should be sensitive in the situation concerned
Sensitive
should reflect changes only in the situation concerned
Specific
should have the ability to obtain data needed
Feasible
should contribute to the understanding of the phenomenon
Relevant
Death is the final common outcome of many health and
nutrition problems. It is a single indicator which can signal
a broad range of health problems
Mortality Indicators
counts all deaths
-all causes
-all ages and both sexes
denominator includes entire population
-all ages and both sexes
Crude mortality rate
counts only deaths in specific age group
-usually calculated for children less than 5 years of age
denominator includes only persons in that age group
Age-specific mortality rate
Counts deaths in children less than 12 months of age, divides by number
of live births in same time period
Infant mortality rate
Counts deaths in women due to pregnancy or child birth, divides by
number of live births in same time period
Maternal mortality rate
Counts deaths in the first 5 years of life, divides by number of live
births in the hypothetical cohort of newborns
Under-5 mortality rate
defined as any departure, subjective or objective, from a state of
physiological or psychological well-being. In practice, morbidity encompasses disease,
injury, and disability.
Morbidity
refers to the occurrence of new cases of disease or injury in a population over a specified period of
time. Although some epidemiologists use incidence to mean the number of new cases in a community, others
use incidence to mean the number of new cases per unit of population.
Incidence
interaction between individuals with a health condition (e.g.
cerebral palsy, Down syndrome and depression) and personal and
environmental factors (e.g. negative attitudes, inaccessible transportation and
public buildings, and limited social supports).
Disability
include obesity, overweight, underweight, and short stature
nutritional status indicators
reflect the equity of distribution of
health resources in different parts of the country
and provision of health care.
Healthcare Delivery Indicators
Doctor -population ratio
Doctor- bed ratio
Population -bed ratio
Population per health center/sub center
Population per traditional health attendant
actual coverage expressed as the proportion of people in need of a service who actually
receive it in a given period, usually a year
Utilization Rates
indicators such as various acts of violence, crime, suicide, homicide, road
accidents, juvenile delinquency, alcohol and drug abuse, smoking, consumption of
tranquillizers and other antisocial activities can be used as guides to improving social
health of the people
Social and Mental Health Indicators
these Indicators reflect the quality of physical and biological
environment in which diseases occur and in which people live.
Environmental Indicators
do not directly measure health. However, these are important in the interpretation of indicators of healthcare.
Socioeconomic Indicators
-rate of population increase
-per capita GNP
-level of unemployment
-dependency ratio
-literacy rates-female literacy
-family size
-housing-density of population at household level
-per capita calorie availability
Allocation of adequate resources to health sector is also an indicator of
political commitment to health.
Health Policy Indicators
he relevant indicators are
1. Proportion of GNP spent on health services
2. Proportion of GNP spent on health-related activities including water,
sanitation, nutrition
3. Proportion of total health resources devoted to primary health care.
defined as a composite measure of physical, mental
and social well-being as perceived by each individual or a group of
individuals including happiness, satisfaction and gratification in health,
marriage, family, work, financial situation, educational opportunities
etc.
Quality of Life Indicators
