Research Methods: Evidence Reviews, PICOT, Hypotheses, and Study Designs

What is a Systematic Review

A structured search and appraisal of multiple studies to answer a specific question

2. What is a Meta-analysis

A statistical combination of compatible quantitative results from multiple studies

3. Does every systematic review include a meta-analysis

No it does not

4. What is a Qualitative Meta-synthesis

Integration of interpretations across multiple qualitative studies

5. What does No evidence of benefit mean

The evidence is currently insufficient to prove a benefit exists

6. What does Evidence of no benefit mean

Adequate evidence suggests the intervention has little or no benefit

7. Which level is at the very top of the evidence hierarchy

Systematic reviews or meta-analyses of high-quality randomized trials

8. Which level is at the very bottom of the evidence hierarchy

Expert opinion or case reports

9. What is the gold standard design for an intervention question

The Randomized Controlled Trial or RCT

10. Can a poorly conducted RCT be less trustworthy than a well-conducted study of a lower design

Yes quality matters more than the rank alone

11. What is the P in PICOT

Population or Problem

12. What is the I in PICOT

Intervention or Exposure of interest

13. What is the C in PICOT

Comparison such as usual care or another intervention

14. What is the O in PICOT

Measurable outcome

15. What is the T in PICOT

Time frame when relevant

16. Is PICO a study design

No it is a question-building tool

17. What does PCC stand for

Population and Concept and Context

18. When is PCC commonly used

For broad or scoping questions

19. What defines a Research Question

A statement of what the study seeks to answer

20. What is a Hypothesis

A testable prediction about a relationship or difference between variables

What is a Null Hypothesis or H0

A statement that there is no difference or no association in the population

22. What is an Alternative or Research Hypothesis

A statement that a difference or association does exist

23. What is a Directional Hypothesis

A hypothesis that specifies the direction of a relationship such as more or less

24. What is a Nondirectional Hypothesis

A prediction that a difference exists but does not specify the direction

25. What does Rejecting the Null Hypothesis mean

The data is inconsistent with the null and something real likely happened

26. What does Failing to Reject the Null mean

The study did not find enough evidence to prove a difference

27. Does failing to reject the null prove that no effect exists

No it does not

28. Do qualitative studies usually test hypotheses

No they generally ask exploratory questions

29. What is an Independent Variable or IV

The presumed influencing variable or intervention

30. What is a Dependent Variable or DV

The measured outcome

31. What is an Extraneous Variable

A variable other than the IV that may affect the outcome

32. What is a Confounder

A variable related to both exposure and outcome that can distort their relationship

33. What is a Conceptual Definition

The abstract meaning of a variable

34. What is an Operational Definition

The specific way a variable is measured or manipulated in a study

35. What is a Primary Source

An original report written by the people who conducted the research

36. What is a Secondary Source

A summary or synthesis of original work like a textbook or review article

37. Is a Systematic Review a primary or secondary source

It is a secondary source because it synthesizes other studies

38. Does Peer Review guarantee that an article is correct

No it is expert scrutiny but not a guarantee of correctness

39. What is the purpose of an Abstract

A brief overview of the question and methods and key results

40. Where would you find the Gap in Knowledge in a research article

In the Introduction or Background section

Which section contains the eligibility criteria and sample size

The Methods section

42. Which section contains the descriptive and inferential statistics

The Results section

43. Which section contains the interpretation of findings and limitations

The Discussion section

44. What is the goal of an Experimental design

To test an intervention using manipulation and control and randomization

45. What are the three requirements for a true experiment

Manipulation and a control group and random assignment

46. What is the purpose of Randomization

To help balance both known and unknown confounders between groups

47. What is a Quasi-Experimental design

A study that tests an intervention but lacks random assignment or a control group

48. What is a Before-and-After study

A quasi-experimental design that measures one group before and after a treatment

49. What is Random Sampling

Selecting participants from a population to be in the study

50. What is Random Assignment

Placing enrolled participants into specific groups like intervention or control

51. Does random sampling imply random assignment

No they are two different things

52. What is Blinding or Masking

Hiding group assignment from participants or researchers to reduce bias

53. What is a Descriptive study

A nonexperimental design that describes characteristics or frequency

54. What is a Correlational study

A design that examines relationships among variables without manipulating them

55. Does correlation prove causation

No it does not

56. What is a Cross-sectional study

A study that measures exposure and outcome at one single point in time

57. What is a Cohort study

A study where groups defined by exposure are followed forward in time for outcomes

58. What is a Case-control study

A study that starts with outcome status and looks back for prior exposures

59. What is Prospective research

Looking forward in time for outcomes

60. What is Retrospective research

Looking backward in time at data that already exists

What is the definition of Probability Sampling

A method where every member of the population has a known and nonzero selection chance

62. What is Simple Random Sampling

Every member of the roster has an equal chance of being picked like a lottery

63. What is Systematic Sampling

Selecting every kth member from a list after a random starting point

64. What is the biggest threat to Systematic Sampling

Periodicity or a repeating pattern in the list that matches the sampling interval

65. What is Stratified Random Sampling

Dividing the population into strata and then randomly sampling within each group

66. What is the purpose of Stratification

To ensure that specific subgroups are represented in the final sample

67. What is Nonprobability Sampling

A method where participants are selected non-randomly which increases bias risk

68. What is Convenience Sampling

Selecting participants who are the easiest to reach or most available

69. What is Quota Sampling

Setting desired numbers for categories and then recruiting nonrandomly to fill them

70. How does Quota sampling differ from Stratified sampling

Quota uses non-random convenience to fill groups while Stratified uses random selection

71. What is Purposive Sampling

Intentionally selecting participants with specific characteristics or experiences

72. In which type of research is Purposive sampling most common

Qualitative research

73. What is Snowball Sampling

A method where initial participants refer others to join the study

74. Who is Snowball sampling best for

Hard to reach or hidden populations

75. What is the definition of Effect Size

A measure of the magnitude or strength of a difference or association

76. What is Statistical Power

The probability of correctly rejecting a false null hypothesis

77. What is the standard target for Statistical Power

80 percent or 0.80

78. When is an A Priori Power Analysis conducted

Before the study starts to estimate the necessary sample size

79. How does a small effect size impact sample size

A smaller effect requires a larger sample to detect it

80. How does high variability in data impact power

More variability reduces the power of the study

What is the danger of a very large study sample

It may detect tiny differences that are statistically significant but clinically unimportant

82. Which test compares the mean of a continuous outcome between two independent groups

Independent samples t-test

83. Which test compares two related measurements such as before and after scores

Paired t-test

84. When is ANOVA used instead of a t-test

When comparing means across three or more groups

85. What does a significant ANOVA result mean

At least one group mean differs but it does not say which ones

86. Which test examines the association between categorical variables using counts

Chi-square test of independence

87. What is the purpose of Pearson correlation

To examine the direction and strength of a linear relationship between two quantitative variables

88. When is Spearman correlation used

For ranked data or non-linear relationships

89. What does ANCOVA do

It compares group outcomes while statistically adjusting for a confounder

90. What is the purpose of Regression

To predict or model an outcome using one or more variables

91. What is Factor Analysis

A technique to identify clusters of related variables

92. What is Alpha or the significance level

The threshold set before analysis usually 0.05 to decide when to reject the null

93. What is a P-value

The probability of obtaining the observed result if the null hypothesis were true

94. If p is less than 0.05 what should the researcher do

Reject the null hypothesis

95. Does a significant p-value prove that an intervention caused the result

No because study design and bias must also be considered

96. What is the range of Pearson r

From negative 1.0 to positive 1.0

97. In correlation what does a positive sign mean

Variables tend to increase or decrease together

98. In correlation what does a negative sign mean

As one variable increases the other tends to decrease

99. Which is a stronger correlation r equals negative 0.80 or r equals positive 0.30

Negative 0.80 because the absolute value is larger

100. What does r near zero indicate

Little to no linear relationship exists