PH3 Flashcards
data analysis DEF
application statistical tests to data
interpretation DEF
explains results
why is biostatistics used in dental hygiene
response to DH therapy
- test products and treatments
- needs of target populations
- evaluates oral health treatment
causes invalid research; number of subjects
insufficient
causes invalid research; too long duration?
no, too short
causes invalid research; incorrect measurements
yes
causes invalid research; correct procedures utilized
no, incorrect procedures utilized
causes invalid research; incorrect statistical tests
yes
2 categorizing data
quantitive
qualitative
quantitive uses
numbers
qualitative uses
observations
qualitative data uses
categorial variables
dichotomous variables
quantitive data uses
continuous variables
discrete variables
qualitative variables; categorial; have numeric representation?
no, no numeric value. just for categorizing
qualitative variables; dichotomous variable places subjects in 2 groups?
yes, they ARE or they are NOT
quantitative variables; does continuous have numeric value?
yes
quantitative variables; how much numeric value?
large/ infinite numbers
what is an example of quantitative variables; continuous
height, weight, time..
quantitative variables; discrete is expressed in what kind of numbers
whole numbers
4 scales of measurement
- nominal
- ordinal
- interval
- ratio
nominal scale; does it have rank?
no and no value
nominal scale; example
color of hair; category
ordinal scale; organized how?
categories; rank ordered
ordinal scale; does the rank order base on equal value
no
ordinal scale; example of rank order with no value.
level 4 does not mean twice as hard as level 2
interval scale; organized
no meaningful zero point
interval scale; AKA no meaningful zero point
arbitrary zero point
interval scale; example
30 degrees is not twice as cold as 60 degrees
interval scale; can be added or subtracted
yes
ratio scale; organized
absolute zero point
ratio scale; can apply all arithmetic?
yes
ratio scale; example
money, weight, height, number of teeth
mean DEF
average
median DEF
midpoint
mode DEF
value occurs most often
what does measuring dispersion do?
communicates how much variation is present in a group of data
3 measures of dispersion
- range
- variance
- standard deviation
range is determined by
subtracting lowest score from highest score
variance represents
average distance
standard deviation is
square root of variance
normal distribution AKA
gaussian distribution
is bell-curve associated with normal distribution
yes
the smaller the sample size significantly reduces the standard error?
no, the large
does mean, median and mode equal value?
yes
what percentage is in ONE SD mean
68%
what percentage is in TWO SD mean
95%
what percentage is in THREE SD mean
99.7%
what is skewing caused by
few extreme scores
negative skewed distribution; what direction of the “Y”
away
positive skewed distribution; what direction of the “Y”
towards
difference between bar graphs and histogram
bar graphs have spaces, histo does not
bar graph; what does the length of the bar mean?
frequency number
frequency polygon is what kind of graph
connect midpoints of bars of a histogram
pie charts are for
lay audience
r value AKA
correlation
positive relationship; what values
increase and increase
inverse relationship; what values
increase and decrease
inverse AKA
negative
does r value always have to be a whole number?
no
r= 1.0
which means
perfect positive correlation
r= -1.0
perfect negative correlation
r= -0.50
moderate negative correlation
r=0.00
no correlation
r= 0.40
low positive correlation
null hypothesis AKA
negative hypo
null hypothesis; what is researcher trying to do?
disprove null hypothesis
research hypothesis AKA
alternative/ positive hypothesis
statistical decision DEF
rather to reject or accept the null hypo based on probability
P value must always equal what number?
EQUAL TO OR LESS than 0.05
P value means
probability value
type error 1 AKA
alpha error
DEF type 1 error
false positive
type 1; null hypo is rejected?
yes, but it should’ve been accepted
type 2 error AKA
beta error
beta error AKA
false negative
type 2; null hypo is rejected?
no. it should’ve been rejected
product and treatment modalities should be based upon what?
documented evidence
refereed AKA
reviewed/ regulated
should one take caution when doing research online
yes
abstract contains
over view
introduction contains
purpose on research study
literature review contains
current information
what is literature review
previous studies
methodology contains
methods and materials
statistical significance is
P value of equal or less than 0.05
not caused by chance
results and discussion contains
summary
statistics and data characteristics
conclusion and recommendation contains
summary