Test 3 Flashcards
what does NCT# stand for
national clinical trials number
what is an NCT#
a number assigned by clinical trials.gov once research protocol is submitted prior to study initiation
what is the purpose of the NCT#
reduce publication bias
who developed clinicaltrails.gov
National Institutes of Health (NIH), through its national library of medicine (NLM) developed site in collaboration with FDA
what is needed for readers to accurately assess a study
complete, clear and transparent information on its methodology and findings
what website can you go to to access all the checklists
equator network
what does CONSORT stand far and what is it used for
Interventional studies- randomized (clinical) trials
CONsolidated Standards Of Reporting Trials
www. consort-statement.org
What does DOI stand for
digital object identifier
what do CONSORT checklist have extension documents for
Non-inferiority and equivalence trials
cluster trials
pragmatic trials
define pragmatic trials
randomized, controlled trial whose purpose is to inform decisions about clinical practice
*philosophy as a continuum, not a dichotomy
what does PRISMA stand for and what type of studies is it used for
interventional studies- systematic review of multiple randomized trials
Preferred Reporting Items for Systemic reviews and Meta-Analyses
www.prisma-statement.org
what does STROBE stand for and what kind of studies is it used for
Observational Studies (cohort, case-control. cross-sectional)
Strengthening the Reporting of Observational studies in Epidemiology
www.strobe-statement.org
what does STROBE checklist have extensions for
Molecular Epidemiology Studies (STROBE-ME)
Genetic Association Studies (STREGA): Strengthening the Reporting of Genetic Association studies
what type of studies is TREND used for and what does it stand for
Transparent Reporting of Evaluations with Non-randomized Designs
Non-randomized studies: reporting evaluations with non-randomized designs of behavioral and public health interventions
www. cdc.gov/trendstatement
what is REMARK used for and what does it stand for
Tumor Marker prognostic studies
REporting recommendations for tumor MARKer prognostic studies
what does GRIPS stand for and what is it used for
Genetic Risk Prediction Studies (used for this as well)
what is STARD used for and what does it stand for
STAndards for the Reporting of Diagnostic accuracy studies
used for diagnostic studies
www.stard-statement.org
what is QUADAS-2 used for and what does it stand for
Systematic reviews of multiple diagnostic studies
Quality Assessment of Studies of Diagnostic Accuracy in Systematic reviews
define population
all individuals
define sample
a subset or portion of the full population
define null hypothesis
a research perspective which states there will be no (true) difference between the groups being compared
what are the 2 key attributes of data measurement (variables)
magnitude (or dimensionality)
consistency of scale (or fixed interval) (equal, measurable spacing between units)
(rational/absolute zero)
define nominal data
Dichotomous/binary; non-ranked named categories
No magnitude/no consistency of scale/ no rational zero
define ordinal data
ranked categories; non-equal-distance
Yes magnitude/no consistency of scale/no rational zero
define interval data
order and magnitude and equal intervals of scale
what types of data is descrete
nominal and ordinal
what types of data is continuous
interval
define variance
difference in each individual measurement value and the groups mean
define standard deviation
square root of variance (restores units of mean)
define parametric
normally-distributed data
define positive skew
when mean is higher than the medial (tail pointing to the right)
define negative skew
when mean is lower than median (tail pointing to the left)
define skewness
measure of the asymmetry of distribution
define kurtosis
measure of the extent to which observations cluster around the mean. for a normal distribution, the value of the kurtosis is zero
what are the required assumptions of interval data
normally-distributed
equal variances
randomly-derived and independent
what do you do if interval data is not normally distributed
transform data to a standardized value (Z-score or log)
use a stat test that DOES NOT require the data to be normally distributed (non-parametric)
define power
(1-type 2 error)
the ability of a study design, its methodology, and the selected test statistic to detect a true difference if one truly exists between group comparisons, and therefore the level of accuracy in correctly accepting/rejecting the null hypothesis
what is the single measurement value most likely to represent the true (yet unknown) difference or relationship between the groups being compared and what is the probability the difference has occurred by chance
p-value
what is the plausible range of possible difference or relationship within which we believe the true difference or relationship may lie
confidence interval
what are confidence intervals based on
variation in sample (V/SD) and sample size (N)
define correlation
provides a quantitative measure of the strength and direction of a relationship between variables (ranges from -1.0 to +1.0)
define partial correlation
correlation that controls for confounding variables
what is the correlation test for nominal data
contingency coefficient
what is the correlation test for ordinal data
spearman correlation
what is the correlation test for interval data
pearson correlation
define survival test
compares the proportion of, or time-to, event occurrences between groups
how are survival tests commonly represented
Kaplan-Meier curve
what is the survival test for each type of data
nominaL; log-rank test
ordinal: cox-proportional hazards test
interval: kaplan-meier test
define regressions
provide a measure of the relationship between variables by allowing the prediction about the dependent, or outcome, variable (DV) knowing the value/category of independent variables (IV’s)
what are the regression tests for each type of data
nominal: logistic regression
ordinal: multinomial logistic regression
interval: linear regression
what are the 4 key questions to selecting the correct stat test
- type of data (does it have magnitude and does the data have a fixed, measurable interval along the entire scale)
- what type of comparison/assessment is desired
- how many groups are being compared
- is the data independent or related (paired)
what test is used for 2 groups of independent nominal data
Pearson’s chi-square test
what test is used for 3+ groups of independent nominal data
chi-square test of independence
what test is used for 2-5 groups of independent nominal data
fisher’s exact test
what does the bonferroni test of inequality test
adjusts the p-value for the number of comparisons being made
what test is used for 2 groups of paired nominal data
mcnemar test
what test is used for 3+ groups of paired nominal data
Cochran
what are the key words for paired data
before and after
what test is used for 2 groups of independent ordinal data
mann-whitney test
what test is used for 3+ groups of independent ordinal data
kruskal-wallis test
what test is used for 2 groups of paired ordinal data
wilcoxon signed rank test
what test is used for 3+ groups of paired ordinal data
friedman test
define the 3 post hoc test for ordinal data
student-newman-keul test: compares all pairwise comparisons possible and all groups are equal in size
dunnett test: compares all pairwise comparisons against a single control (all groups must be equal in size)
dunn test: compares all pairwise comparisons possible (groups do not need equal size)
what test is used for 2 groups of independent interval data
student t-test
what test is used for 3+ groups of independent interval data with 1 DV
ANOVA
what test is used for 3+ groups of independent interval data with 2+ DV
MANOVA
what are ANOVA and MANOVA comparing
the means of all groups
define ANCOVA
compares the means of all groups against a single DV while also controlling for co-variance of confounders (3+ groups of independent interval data with confounders)
define MANCOVA
compares the means of all groups against multiple DVs while also controlling for the co-variance of confounders (2+ DVs and 3+ groups of independent data with confounders)
when is a paired t test used and what does it do
2 groups of paired interval data
compares the mean values between groups that are related
when is a repeated measures ANOVA used
1 DV
3+ groups of paired interval data
compares the means of all groups of related data against a single DV
when is a repeated measures MANOVA used
2+ DVs
3+ groups of paired interval data
compares the means of all groups of related data against multiple DVs
what does repeated measures ANCOVA do
compares the means of all groups against a single DV while also controlling for the covariance of confounders
3+ groups of paired data with confounders
what does repeated measures MANCOVA do
compares the means of all groups against multiple DV while also controlling for the covariance of confounders
3+ groups of paired data with confounders
what are the post-hoc tests for interval data
student-newman-keul test dunnett test dunn test tukey/scheffe test bonferroni correction
define Tukey/Scheffe tests
compares all pairwise comparisons possible
all groups must be of equal size
tukey test is slightly more conservative than SNK
scheffe test less affected by violations in normality and homogeneity of variances-most conservative
define kappa statistic
agreement between evaluators (consistency of decisions)
