Cross-Sectional and Longitudinal Studies infographic description

The infographic is titled, Thinking Critically About: Cross-sectional and longitudinal studies. The learning objective question 10-10 reads, what are cross-sectional studies and longitudinal studies, and why is it important to know which method was used? The first section shows an illustration, which depicts five people of different age groups taking up a written test. Text above the illustration reads researchers using the cross-sectional method study different age groups at one time. They have found that mental ability declines with age (Wechsler, 1972). The first section leads to the second section.

Text on the second section reads, comparing 70-year-olds and 30-year-olds means not only comparing two different people but also two different eras. These researchers were comparing: Generally less-educated people open parenthesis born in the early 1900's close parenthesis with better-educated people open parenthesis born after 1950 close parenthesis.

People raised in large families with people raised in smaller families.

People from less-affluent families with people from more-affluent families.

The third section shows an illustration which depicts people of different age groups taking a written test; the people are categorized into three groups; the starting year of the first group is 1950 and the ending year of the third group reads, present. Text above the illustration reads, researchers using the longitudinal method study and restudy the same group at different times in their life span. They have found that intelligence remains stable, and on some tests it even increases (Salthouse, 2010, 2014; Schaie and Geiwitz, 1982). The third section leads to the fourth section.

Text on the fourth section reads, but these studies have their own issue. Participants who survive to the end of these studies may be the healthiest and brightest people. When researchers statistically adjust for the loss of less intelligent participants, intelligence does appear to decline somewhat in later life, especially after age 85. An illustration beside the text depicts a tombstone with a flower. Text on the tombstone reads R I P (Brayne et al., 1999).