Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Neontal boards J > Statistics > Flashcards

Statistics Flashcards

1
Q

What are the type of variables

A

Nominal
Ordinal
Interval
Ratio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

It is a type of variable with no value

A

Nominal (name)- gender, blood type

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

It is a variable with order/superiority but no magnitude difference

A

Ordinal (order)- stage of NEC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

It is a variable with equal interval but no zero

A

Interval- body temp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

It is a variable with equal interval with meaningful zero

A

Ratio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Tests for normal distribution

A

parametric test

  • T-test
  • ANOVA
  • Pearsons correlation

Can only be used on interval and ratio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Nominal data with only 2 groups

A

dichotomous or binary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

it is a variable that is the outcome

A

Dependent variable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

it is the variable that is the intervention

A

independent variable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Tests for skewed distribution, ordinal and nominal variable

A

non-parameteric
Wilcoxon rank sum test
kruskal-wallis test
Spearmans rank correlation coefficient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

measure of central tendency that is the sum of all observation

A

mean “average”
- can be influenced by outlying value

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

measure of central tendency that is the middle value of date

A

Median

  • more appropriate for skewed data
  • commonly used for ordinal data like apgar score
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

measure of central tendency that is most frequently occuring

A

Mode
- commonly used with nominal data

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

It is the bell shaped frequency distribution where the mean, median, mode are the same

A

Gaussian distribution/ Normal distribution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

It is how flat or peaked the curve

A

Kurtosis

  • peaked >0 leptokurtic
  • normal 0 mesokuritc
  • lower and broad <0 platykuritc

Note: all are symmetric

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

In skewed data, basis of terminology

A

It based on the tail

  • right- positive
  • Left- negative

If mean> median, right
If mean<median, left

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

It is the measure of dispersion which is the difference between the highest and lowest value

A

Range

  • dependent on sample size
  • influenced by extreme values
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

It is the measure of dispersion which is the difference between the median of the lower half and upper half of the data

A

Interquartile range

  • between 25th and 75th percentile
  • less influenced by extreme value
  • comprises middle 50% of the data
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

It is the deviation from the mean

A

Variance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

It is the square root of variance, how close a cluster is to the close to the sample mean

A

Standard deviation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Meaning of standard deviation if mean is known and has normal distribution

A

1 SD- 68.2% (34.1 %- left or right)
2 SD- 95.4% (47.7%)
3 SD- 99.8% (48.9%)

  • know this- can compute for percentage of the sample is included
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

It is the SD of the error of the sample mean in relation to the true mean of the total population

A

Standard error of the mean

  • how close is the sample mean close to the population mean
  • inc the sample size, SEM decreases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

it is a hypothesis with one predictor and one outcome

A

simple hypothesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

It is a hypothesis with several predictor variable

A

complex hypothesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

It is the hypothesis that proposes no difference between groups

A

null hypothesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

It is the hypothesis that proposes an association

A

alternative hypothesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

it is a parametric test to compare 2 groups that are continuous, normal distributed

A

T-test

  1. Paired: subject his own control (before and after)
  2. Unpaired: two groups compared
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Extension of T-test with three or more groups

A

Analysis of variance (ANOVA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

It is the comparison for further exploration of data after significant effect

A

Post hoc comparison

30
Q

Test used for ordinal data

A

Wilcoxon rank
mann-whitney U

31
Q

Test for categorial data

A

Chi-squared test
Fisher exact test

32
Q

Type of error that rejects the null hypothesis when it is true

A

Type I false positive

Reduced by more stringent P (influenced by: sample size, difference of control and expe, less variance)

33
Q

Type of error that fails to reject the null hypothesis

A

Type II false negative

Reduced by increasing sample size, power of the study

34
Q

It is the probability the null hypothesis is true by chance

A

P-value

P value 0.05 means 5% chance the null hypothesis is true to chance alone (5% na swerte lang) or 95% the sample represents different population (the groups are different, talagang magkaiba)

35
Q

true or false lower p-value has a higher strength of association or importance of association

A

False

Remember p-value the null hypothesis is true by chance alone

36
Q

What is bonferroni correction

A

Interpreting the P value when multiple comparison- need to be more stringent due to higher likelihood of type I error
- p value/ number of comparison

37
Q

It is the range of values you expect the actual mean of the true population

A

Confidence interval

38
Q

It is the probability of including the population mean within the confidence interval

A

Level of confidence

A high level of confidence will widen the range (the lower the confidence, the narrower the range)

39
Q

Absolute risk

A

the number of subjects who develop the disease among the exposed

  • a/a+b
40
Q

Absolute risk reduction

A

the absolute effect of the exposure
% outcome of exposure- % outcome from non exposure

  • a/(a+b)- c/(c+d)

Also known as risk difference or attributable risk

41
Q

Number needed to treat

A

the reciprocal of absolute risk reduction

  • 1/(c/(c+d))-((a/a+b))

As the difference in group increases, the lower NNT

42
Q

Relative risk reduction

A

(control event rate- experiment event rate)/ control rate

  • (c/c+d)- (a/a+b)/ (c/c+d)

If its negative: protective

If its positive: harmful

43
Q

It is the probability of the outcome in the exposed vs in unexposed

A

Relative risk or risk ratio

  • (a/a+b) / (c/c+d)

Interpretation:

> 1 positive association

< 1 negative association

44
Q

Its the improvement in outcomes simply as a result of being involved in astudy

A

Hawthorne effect

45
Q

How does randomization reduce bias

A

By creating two groups of individuals that have equal likelihood of having the outcome of interest

46
Q

It is an observational study useful for rare diseases

A

Case control

47
Q

the probability of rejecting the null hypothesis when the alternative hypothesisis true

A

Statistical power

(1-Type II error rate)

48
Q

It is the probability of rejecting the null hypothesis when it is true

A

Type I error

49
Q

It is the probability of accepting the null hypothesis when the alternative is true

A

Type II error

50
Q

Statistical power depends on

A
  1. increasing the significance criteria (p value)
  2. increasing the magnitude of effect (difference or change)
  3. increasing the sample size
51
Q

Deaths that occur between 22 weeks’ gestation and 7 days of postnatal life

A

Perinatal mortality

52
Q

deaths in the first 28 days of life

A

Neonatal mortality

53
Q

Death occuring within the 1st year of life

A

Infant Mortality

54
Q

It shows the difference in the rate of a condition between individuals with and without a specific exposure

A

Attributable risk

Best study or research design: Cohort study

55
Q

Of the measure of central tendency, which should be equal to show normal distrubution

A

Mean and median

Mean> median- skewed to the right

Mean<median skwed to the left

56
Q

Cummulative incidence = Incidence rate

A

period of observation is short

disease prevelence is low

duration of disease is same for the exposed and non exposed

57
Q

Effect of prevalence in predictive value of a test

A
  • increased: increase PPV, dec NPV
  • decreased: dec PPV, inc NPV
58
Q

It the ability of a test to correctly identify individuals who have a condition

A

sensitivity

59
Q

It is the ability of a test to correctly identify individuals who do not have a condition

A

specificity

60
Q

It presents as the proportion of individuals with a positive test result who have a condition

A

Positive predictive value

  • affected by disease prevalence; when a disease is more prevalent, the PPV is higher.
61
Q

It presents the proportion of individuals with a negative test result who do not have the condition

A

Negative predictive value

  • affected by disease prevalence; when a disease is more prevalent, the NPV is lower.
62
Q

It is used assess a diagnostic test’s accuracy whose results are continuous variables.

A

Receiver operating characteristic (ROC) curves

63
Q

The best clinical design for evaluating intervention for clinical practice

A

randominzed controlled trial

64
Q

what decreases bias in RCT

A
  1. randomization
  2. blinding
65
Q

It is the statistical method in a systematic review, data from individual studies combined to give a summary of the effectiveness of an intervention with a 95% confidence interval

terms used: estimate relative risk (RR), RR reduction, or odds ratio

A

Meta-analysis

It increases power and precision of estimates of treatment effects and exposure risks

66
Q
  • It is the variation among studies in a meta analysis
  • It is measured using I2 statistic
A

Heterogenicity

Interpretation of heterogenicity:
0% to 40%: might not be important
30% to 60%: may represent moderate heterogeneity
50% to 90%: may represent substantial heterogeneity
75% to 100%: considerable heterogeneity

67
Q

what are the definition of mortality
a. fetal death
b. infant death
c. maternal death

A

a. fetal- death prior to expulsion or extraction of product of human conception regardless of duration of pregnancy
b. live birth- expulsion of product of conception from mom irrespective of durwtion of pregnancy, baby has evidence of life- beating heart, pulsation of the umbilical cord or movement of voluntary muscle
c. death of woman while pregnant or within 42 days of pregnancy

68
Q

what is a SMART objective

A

specific
measurable
achievable
relevant
time-bound

69
Q

What are the type of validity

A
  1. internal validity: results of the study are true or are they a result of the way the study was designed or conducted.
  2. External validity: generalizability of results to other settings or samples.
70
Q

odd ratio

A

OR= ad/bc
- odds in exposure/odds in the nonexposed

OR= (a/b)/(c/d)

71
Q

When does odd ratio and risk ratio almost the same or approximate

A

Outcome is rare

72
Q

Statistical tests

A

Neontal boards J (19 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions