You don't need to know this study, but the results are really useful for discussing individual differences in memory and it's a good example of a cognitive field experiment.
LOFTUS' RESEARCH INTO INDIVIDUAL DIFFERENCES IN MEMORY
When studying individual differences in memory, researchers focus on two types of memory:
Loftus et al. (1992) investigated these variables with an opportunity sample of 1989 visitors to a Science Museum in San Francisco. The sample included children and the elderly as well as adults from different backgrounds.
Visitors watched a 75-second film of a crowd scene, at the end of which a man is nearly run over by a van and assaulted by an officer with a baton. They were later asked 10 questions about the episode on a computer screen. 6 yes/no questions measured Accuracy; there were 2 leading questions (half the participants were misinformed about the colour of the van and the officer's uniform) and 2 questions measuring Suggestibility (asking about the colour of the van and the officer's uniform).
This was a field experiment, because the participants were real visitors to the Science Museum. The IV is (1) whether or not the participants were given leading questions and the DVs are whether they falsely recalled a white van and white uniform and their score for Accuracy. It uses Independent Groups design (because half the participants were put in the Suggestibility group by being given a leading question and the other haldf was a Control group who did not get a leading question).
However, it is also a natural experiment, because Loftus et al. recorded the (2) age, (3) occupation, (4) gender and (5) educational level of participants for comparison purposes. These are naturally-varying IVs.
Loftus found that average accuracy was 74%. 26-35 year-olds were most accurate (77%) and the elderly (age 65+) group were the least accurate (56%). Children (age 5-10) and the elderly (age 65+) got the lowest scores for accuracy and were also the most suggestible.
Males and females scored similarly, except in the elderly group, where females were much more accurate than males (69% versus 43%).
The unemployed were the least accurate (65%) and people working in trade/technical scored the highest (77%). Oddly, accuracy was low for lawyers (66%) and the police (68%). Artists got unusual scores: they were average for accuracy, but very suggestible (54% affected by leading questions compared to 17% in the artists control group).
Education did make a difference, with the most educated groups being more accurate but suggestibility was not affected by education.
Loftus concludes that there are individual differences in memory ability, both in accuracy and suggestibility.
APPLYING PSYCHOLOGY TO INDIVIDUAL DIFFERENCES IN MEMORY
EVALUATING INDIVIDUAL DIFFERENCES IN MEMORY (AO3)