Got it. I'll slow it down and actually explain things so you can understand, not just memorize.
🔬 Research Methods – Full Study Guide (Clear + Complete)
1. Variables (this is foundational)
In any study, you are dealing with variables.
The independent variable (IV) is what the researcher changes or controls. Think: the cause.
The dependent variable (DV) is what gets measured. Think: the effect.
Example:
If a study tests whether exercise lowers heart rate:
Exercise = independent variable
Heart rate = dependent variable
If a question says the dependent variable is manipulated, that is wrong.
2. Levels of Evidence (which studies are strongest)
Not all studies are equal. Some are more reliable than others.
From strongest to weakest:
Systematic reviews and meta-analyses (they combine multiple studies)
Randomized Controlled Trials (RCTs)
Cohort studies
Case-control studies
Cross-sectional studies
Case studies or reports
Key idea:
If something asks for the highest level of evidence, it is NOT a cohort study. That statement is false.
3. Study Designs (you need to recognize these instantly)
Case Study
This focuses on one person or a very small group. It gives deep detail but cannot be generalized to everyone.
Cross-Sectional Study
This looks at data at a single point in time.
Think of it as a snapshot.
Example: surveying people today about their diet and weight.
It tells you what is happening, not what caused it.
Cohort Study
This follows a group of people over time.
You start with an exposure (like smoking) and track what happens.
Example: follow smokers vs non-smokers for 10 years and see who develops lung disease.
Case-Control Study
This starts with the outcome, then looks backward.
Example:
Group 1: people with cancer
Group 2: people without cancer
Then you look back to see differences (like smoking history)
Your exam cancer question = case-control study
4. Validity (this is heavily tested)
Validity asks: are we measuring what we think we're measuring?
Internal Validity
This is about cause and effect.
It asks: did the independent variable actually cause the change?
High internal validity means:
Few confounding variables
Strong control
External Validity
This is about generalization.
It asks: can we apply these results to the real world?
Example:
If a study only used college athletes, can you apply it to older adults? Probably not.
Construct Validity (most important type)
This asks whether the test truly measures the concept.
Example:
If you're measuring intelligence, does your test actually measure intelligence—or just memory?
Face Validity
This is the weakest type.
It just means the test looks like it works.
No deep proof.
5. Reliability (consistency)
Reliability asks: are the results consistent?
Intrarater Reliability
Same person measures something multiple times and gets the same result.
Interrater Reliability
Different people measure the same thing and get the same result.
6. Bias (common mistakes in research)
Bias is anything that skews results.
Sampling Bias
Your sample does not represent the population.
Example: only surveying athletes when studying all adults.
Hawthorne Effect
People change behavior because they know they are being watched.
Experimenter Bias
The researcher unintentionally influences results.
Placebo Effect
People improve because they believe they are receiving treatment.
7. Peer Review
Before research is published, experts evaluate it.
This is called the peer review process.
It helps catch errors and improves quality.
8. Primary Sources
A primary source is original research.
Always better than summaries when possible.
9. MAXICON Principle
This principle is about reducing error.
If a statement says it minimizes true variance, that is wrong.
It minimizes error, not real differences.
10. Research Proposal
A proposal includes:
Introduction
Literature review
Methods
It does NOT include results yet.
11. Sampling Methods
Random Sampling
Everyone has an equal chance.
Stratified Random Sampling
You divide people into groups (like age or gender), then sample from each.
This improves representation.
Convenience Sampling
You take whoever is easy to access.
This is weak and often biased.
12. Inclusion vs Exclusion Criteria
Inclusion criteria = who is allowed in the study
Exclusion criteria = who is not allowed
13. Power Analysis
This determines how many participants you need.
Too few = unreliable results
Too many = waste of resources
14. Likert Scale
This is a rating scale.
Example:
Strongly agree → Agree → Neutral → Disagree → Strongly disagree
15. Controlling Bias (important short answer)
Ways to reduce bias:
Randomization (assign groups randomly)
Blinding (participants or researchers don't know groups)
Control groups
Standard procedures
16. Hypothesis
A hypothesis is a testable prediction.
It must clearly connect variables.
Example:
"People who sleep more will have faster reaction times."
17. Research Process (know this order exactly)
Identify the problem → Review literature → Form hypothesis → Design study → Collect data → Analyze data → Draw conclusions → Communicate results
18. Research Protocol (what goes into a study plan)
A protocol includes:
The research question
Study design
Sample/population
Inclusion and exclusion criteria
Variables and how they are measured
Data collection methods
Data analysis plan
Ethical considerations
🧠What You Actually Need to Be Ready For
Most questions are pattern recognition. Here's how to think:
"At one point in time" → cross-sectional
"Looking backward" → case-control
"Following over time" → cohort
"Generalize results" → external validity
"Cause and effect control" → internal validity
"Same tester repeating" → intrarater reliability
"People act different when watched" → Hawthorne effect
If you want to lock this in fast, I can run you through a realistic practice test that matches your exam exactly.