A researcher is studying election anxiety in 2025, but a major political scandal breaks out! What bias?
History Bias
This concept helps researchers compare reality to what could have been.
The counterfactual.
If you were researching a hard-to-reach population, you might use this sampling method where one person leads you to another, and so on.
Snowball method
A sampling method where we grab whoever’s closest—like picking the first people you see at a coffee shop!
A non-probability sampling method where participants are selected based on availability, accessibility, or ease of recruitment, rather than through a random selection process.
A scale at the gym always adds five extra pounds, making everyone to panic! What type of bias is this?
Measurement Bias.
Bias associated with data collection methods (type of methods used, social desirability, recall bias, researcher bias)
An evaluation design that allows all the participants to get the intervention.
The Switching Replication design
In experiments, researchers sometimes create 'twin' groups by ensuring participants are similar in key characteristics like age, gender, and motivation. What are these characteristics called?
Matching Variables
Why reinvent the wheel? Name an advantage of using an existing standardized survey.
advantage: already piloted, used, analyzed; reliability and validity established; allow for comparison with other studies
You think your study found the secret to perfect health—but wait! Sneaky outside factors may have been pulling the strings behind the scenes. What is this research troublemaker called?"
Confounding factors that threaten internal validity.
Name the design in which the pretest serves as a counterfactual.
Reflexive Control
Pretest serves as counterfactual
Matching people by their favorite pizza topping? Probably not helpful. But matching by age, gender, or income? Now that makes sense! Why is that?
Matching variables should be directly related to the outcome of interest to control for confounding factors.
Arbitrary characteristics (like pizza topping preference) don’t affect the study results and are irrelevant.
Do you love pizza and always eat pineapple on it?
What is the issue with this question?
Double-barreled
A study measures children’s reading skills over five years but forgets one tiny detail… kids grow up
Maturation bias. A change occurs in participants as a result of maturation or passage of time (teens aging, and becoming better educated)
Kids grow up and naturally get better at reading!
This study design is like a detective tracking clues over time! Researchers gather lots of data before a big event—like a new health policy—then keep watching afterward to see if the trend takes a dramatic twist. What is this method called?
Interrupted Time-Series (ITS)
Scientists love fairness! In this method, participants don’t get to pick their fate—luck does!
Random Assignment to experimental and control groups.
When researchers look for the rule-breakers or outliers to understand what makes them different, what type of sampling are they using?
Deviant case sampling
Study people can choose their assignment group. What bias?
Selection bias
Sometimes, flipping a coin to decide who gets a life-saving treatment just isn’t ethical! Other times, it’s too expensive, too slow, or just plain impossible. Researchers might skip this 'gold standard' study design in these cases. What is it?
Randomized Control Trial
A sampling method where people are selected because they offer unique insights.
Deviant case sampling
In qualitative research, researchers don’t just collect stories—they check back with participants to ensure they got the story right!
It ensures accuracy and credibility and helps improve the trustworthiness of qualitative research!