{"id":11778,"date":"2019-02-09T11:32:59","date_gmt":"2019-02-09T02:32:59","guid":{"rendered":"https:\/\/themantic-education.com\/ibpsych\/?p=11778"},"modified":"2019-02-08T11:34:04","modified_gmt":"2019-02-08T02:34:04","slug":"lesson-idea-understanding-generalizability-and-population-validity","status":"publish","type":"post","link":"https:\/\/www.themantic-education.com\/ibpsych\/2019\/02\/09\/lesson-idea-understanding-generalizability-and-population-validity\/","title":{"rendered":"Lesson Idea: Understanding generalizability and population validity"},"content":{"rendered":"

If you want to write excellent evaluations of psychological studies then\u00a0generalizability\u00a0<\/strong>is a really important term to know. It’s also called\u00a0external validity<\/strong> and it refers to the extent to which we could expect the same results in a different context (i.e. do the results apply beyond the study, external to the study?).<\/p>\n

In this post we’ll focus on\u00a0population validity (read more here)<\/a>.\u00a0<\/strong>Strictly speaking, population validity refers to how well the sample represents the target population – is the sample an accurate representation so that we’d be able to generalize our results to the broader group. It can also be used to assess the extent to which results from one sample could apply to a different group of people.<\/p>\n

When you’re evaluating a study based on generalizability what you’re really doing is evaluating the conclusions<\/em> of that study.\u00a0 So for population validity, we’re asking “would those conclusions apply to everyone? Are there specific groups they might not apply to and why not?”<\/p>\n

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If a study is done on all women, we might ask if we’d expect the same results with men. This is an example of thinking about generalizability. (Photo by rawpixel.com on Pexels.com)<\/p><\/div>\n

For example: “If one study used all females and concluded that there’s a relationship between testosterone and aggression, could we apply these findings to males as well? Males naturally have higher levels of testosterone and perhaps this has led to other biological differences that might affect the processing of testosterone in the body. Moreover, if the findings of the study were being applied to explain high testosterone levels in prison populations, the all-female participants also raises the question of population validity as a majority of violent criminals (statistically speaking) are males. Thus, the nature of the sample in the study raises questions about the generalizability of the possible applications.” (From\u00a0IB Psychology: A STudent’s Guide<\/a> pg35).<\/em><\/p>\n

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Activity<\/h3>\n

Read the following list of studies with a brief description of the sample (i.e. participant characteristics) and the conclusions drawn from these studies. Discuss limitations of these studies in terms of population validity. The key to a good explanation is to pick a group or population that you think the results wouldn’t apply to and explain\u00a0why not!<\/em><\/p>\n

Testosterone and the amygdala (Radke et al):\u00a0<\/strong>This study used 54 healthy females with an average age of 21 (range of 18-30 to test the effects of testosterone on the amygdala when someone is threatened. The results showed increased testosterone increased activity in the amygdala when responding to threat. One conclusion from this study is that testosterone may cause aggression because it increases activity in the amygdala.<\/p>\n