#1
What is the purpose of blinding in a clinical trial?
To prevent participants from dropping out of the trial
To ensure that participants are treated equally
To prevent bias in the assessment of outcomes
To make the trial more cost-effective
#2
Which of the following is NOT a measure of central tendency?
#3
Which of the following is a measure of the spread or dispersion of data?
Mean
Median
Standard deviation
Mode
#4
What is the purpose of a control group in an experiment?
To provide a baseline for comparison to the experimental group
To ensure that the experiment is conducted ethically
To manipulate the independent variable
To increase the statistical power of the study
#5
Which of the following is NOT a requirement for conducting a valid experiment?
Random assignment
Blinding
Matching
Control group
#6
What is the purpose of randomization in experimental design?
To ensure that all subjects in the experiment are identical
To minimize the effects of confounding variables
To increase the statistical power of the study
To guarantee that the experiment will produce significant results
#7
Which statistical test is appropriate for comparing the means of two independent groups?
Paired t-test
ANOVA
Independent samples t-test
Chi-square test
#8
In a normal distribution, what percentage of the data falls within one standard deviation of the mean?
#9
What is the purpose of a pilot study in research?
To test the feasibility of the research design and procedures
To ensure that the study will produce statistically significant results
To recruit a large sample size for the main study
To analyze the final results before publication
#10
Which statistical test is appropriate for determining the association between two categorical variables?
Independent samples t-test
Chi-square test
ANOVA
Correlation analysis
#11
What does the p-value in hypothesis testing represent?
The probability of making a Type I error
The probability of making a Type II error
The probability of obtaining the observed results if the null hypothesis is true
The probability of obtaining a statistically significant result
#12
Which of the following best describes a factorial design in experimental research?
A design where participants are randomly assigned to different levels of a single independent variable
A design where multiple independent variables are manipulated simultaneously
A design where participants are matched based on certain characteristics before assigning them to different groups
A design where participants serve as their own controls
#13
What is the formula for calculating the coefficient of determination (R-squared) in linear regression?
1 - (SSR / SST)
(SST - SSR) / SST
(SSE / SST)
1 - (SSE / SST)
#14
What is the purpose of a crossover design in clinical trials?
To compare the effects of different treatments in a single group of participants
To ensure blinding of participants and researchers
To minimize carryover effects from one treatment period to another
To recruit a larger sample size for the study
#15
What is the primary purpose of an intention-to-treat analysis in clinical trials?
To analyze only the participants who completed the study according to the protocol
To account for all randomized participants, regardless of their adherence to the assigned treatment
To match participants in the experimental and control groups
To adjust for confounding variables in the analysis