US Preventative Services Task Force
develop evidence-based guidelines for healthcare
Cochrane Collaboration
develop and disseminate systemic
... [Show More] reviews of healthcare interventions
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Florence Nightingale David
produced the first edition of Tables of the Correlation Coefficient
population
The entire group having some characteristic (eg, all people with depression, all residents of the United States). Often a sample is taken of the population and then the results are generalized to that population.
sample
A group selected from the population in the hope that the smaller group will be representative of the entire population.
parameter
characteristic of a population
statistic
characteristic of a sample
descriptive statistic
numerical or graphical summaries of data, and may include charts, graphs, and simple summary statistics such as means and standard deviations to describe characteristics of a population sample
inferential statistics
statistical techniques (e.g., chi-square test, the t test, the one-way ANOVA) that allow conclusions to be drawn about the relationships found among different variables in a population sample
quantitative variables
a characteristic that can be measured numerically, a characteristic with numeric values that have meaning and for which arithmetic operations such as adding and averaging make sense. Ex: height, weight, income, heart rate, etc.
categorical variables
a characteristic that takes on values that are names or labels.These are data that cannot be averaged or represented by a scatter plot as they have no numerical meaning. Ex: The color of a ball, gender, year in school.
data
the raw materials of research, they provide the numbers upon which we perform statistics
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variables
any characteristic that can and does assume different values for the different people, objects, or events being studied
random assignment
Assignment of individuals to groups by chance (ie, every subject has an equal chance of being assigned to a particular group). [Show Less]