Linda is conducting a federally-funded research project that examines literacy skills in middle school learners. Bonnie recently started a new study that specifically focuses on reading strategies. Some of the students are participating in both studies.
◦ This is mostly a threat to external validity.
◦ This is of no concern because there are two different studies.
◦ This is an example of the placebo effect.
◦ This is a mostly a threat to internal validity.