LO5 May 21

name 5 tools that have helped consumers appraise research

CEBM, Consort, QUOROM, STARD, MOOSE

4 uses of statistics for dental professionals

designing, evaluating effectiveness, determining treatment, interpretation of scientific literature

What is statistics?

is the science of collecting, organizing, analyzing, and interpreting data in order to make decisions

two branches of statistics

descriptive and inferential

what is biostatistics?

data analysis and interpretation in health care research

What is data (singular: Datum)?

consists of information coming from observations, counts, measurements, or responses that the researcher collects

what is an item of data?

each piece of info

what’s a data set?

group of all data items

what’s raw data?

collected data/info that has not been organized numerically

what’s grouped data?

data/info that is organized and summarized

What’s a population?

the collection of all possible individuals, objects, measurements, or counts of interest

what’s a sample?

a portion, part or subset of the population of interest

what’s a parameter?

a numerical description of a population characteristic (data collected from entire population)

what’s a statistic?

a numerical description of a sample characteristic (data collected from a sample of the group being studied)

what’s an observational study?

a researcher observes and measures characteristics of interest of part of a population

what’s an experiment?

a treatment is applied to a part of a population, and responses are observes

what’s a survey?

an investigation of one ore more characteristics of a population

random samples are representative of the source _______

population

non random samples are NOT _____________: may be biased, regarding age, condition, socioeconomic status

representative

what’s a stratified sample?

has members from each segment of a population, ensures that each segment from the population is represented

what’s a systematic sample?

a sample in which each member of the population is assigned a number, a starting number is randomly selected and sample members are selected at regular intervals

What does N stand for?

how many data points are in your population

what does n stand for?

desired sample size

what’s a rth value?

sampling interval

how to calculate rth value

N/n

what’s a convenience sample?

consists only of available members of the population

what’s a judgement sample?

provides a sample through personal judgement of subjects who would be most appropriate and representative of a population

what’s a variable?

any characteristic that can be measured, observed, or manipulated in research

What’s an independent variable?

those variables that are manipulated or controlled by the researcher. The treatment or invention (x axis)

what’s a dependent variable?

those variables that are measured as an outcome or result of the manipulation (y-values on graph)

______ variable affects ______ variable

independent, dependent

what’s a controlled variable?

the characteristics that are kept the same in order to ensure that the independent variable is the influencing factor ie; age, gender

what’s an extraneous variable?

other less important characteristics that may inadvertently influence the results of the study, the researcher may attempt to control these or use these to adjust the results of the study

what are the four levels of measurement?

nominal, ordinal, interval, ratio

what’s nominal level of measurement?

mutually exclusive categories, no rank or value, no numeric relationship between the classifications (ie ethnic groups)

what’s ordinal level of measurement?

mutually exclusive categories that are rank ordered (ie: DD levels)

What’s an interval level of measurement?

includes rank and ordering and this additional characteristic: equal intervals or distances between adjacent nymbers

what’s ratio level of measurement

includes rank ordering, equal intervals , and this additional characteristic: an absolute zero point

How is nominal level of measurement measured?

qualative

how is ordinal level of measurement measured?

qualative or quantitive

how’s interval level of measurement measured?

quantitative

how’s ratio level of measurement measured?

similar to interval level but a zero entry is meaningful

whats descriptive statistics?

used to summarize, organize, and describe quantitative data

what’s interential statistics?

used to make inferences (generalizations) about a population based on data taken from a sample

what’s frequency?

a statistical term for a count of how many cases there are in particular category of a particular variable

how do we create frequencies?

by sorting data by value or category and then summing the cases that fall into those values

what’s proportion?

compares the number of cases in a given category with the total size of the distrubution

what’s the percentage?

is the frequency of occurrence of a category per 100 cases

4 methods of measuring oral disease

counts, proportions, rates, indices