{"id":758,"date":"2023-03-08T17:54:05","date_gmt":"2023-03-08T17:54:05","guid":{"rendered":"https:\/\/content.one.lumenlearning.com\/introstatstest\/chapter\/observational-study-learn-it-1\/"},"modified":"2025-10-05T14:40:47","modified_gmt":"2025-10-05T14:40:47","slug":"observational-study-learn-it-1","status":"publish","type":"chapter","link":"https:\/\/content.one.lumenlearning.com\/introstatstest\/chapter\/observational-study-learn-it-1\/","title":{"raw":"Observational Studies: Learn It 1","rendered":"Observational Studies: Learn It 1"},"content":{"raw":"<section class=\"textbox learningGoals\">\r\n<ul>\r\n\t<li>Recognize observational studies and list the key components<\/li>\r\n\t<li>Describe confounding factors that may influence an association<\/li>\r\n<\/ul>\r\n<\/section>\r\n<h2>Observational Studies<\/h2>\r\n<p>In an <strong>observational study<\/strong>, a researcher will observe an outcome without interfering. Instead of trying to assess cause and effect, an observational study is typically used when the goal is to learn about characteristics of a population or to compare groups within a population with respect to some characteristic. Sometimes observational studies are used because they might be the only way certain types of questions can be studied.<\/p>\r\n<p>When designing an observational study, researchers are often looking for a relationship between two variables.<\/p>\r\n<section class=\"textbox keyTakeaway\">\r\n<h3>explanatory variable (factor of interest)<\/h3>\r\n<p>The <strong>explanatory variable<\/strong> is the independent variable that is of interest to the researcher.<\/p>\r\n<\/section>\r\n<p>The explanatory variable is what researchers change or select to see how it affects something else; it's the \"cause\" or input that helps explain why an outcome happens.\u00a0<\/p>\r\n<section class=\"textbox keyTakeaway\">\r\n<h3>response variable (response factor)<\/h3>\r\n<p>The <strong>response variable<\/strong> is the dependent variable that allows the researcher to objectively compare the differences.<\/p>\r\n<\/section>\r\n<p>The response variable is what researchers measure to see if it changes based on the explanatory variable; it's the outcome or result being studied.\u00a0<\/p>\r\n<section class=\"textbox example\" aria-label=\"Example\">\r\n<ul>\r\n\t<li>Hours of sleep (explanatory variable) might explain test scores (response variable)<\/li>\r\n\t<li>Amount of rainfall (explanatory variable) might explain crop yields (response variable)<\/li>\r\n<\/ul>\r\n<\/section>\r\n<p>In observational studies, researchers can only observe and measure what naturally occurs; they cannot assign participants to different groups, control the conditions, or isolate specific variables like they would in an experiment. Due to a lack of control, observational studies may inherently be at risk of containing <strong>confounding<\/strong> biases, which are outside of the control of the researcher.\u00a0<\/p>\r\n<section class=\"textbox keyTakeaway\">\r\n<h3>confounding variable<\/h3>\r\n<p>A confounding variable is a variable that was not accounted for in a study and may actually influence other variables in the study.<\/p>\r\n<\/section>\r\n<section class=\"textbox proTip\">\r\n<p>An observational study can show an association<em>\u00a0<\/em>between variables, but it cannot establish a cause-and-effect relationship since the researchers are not controlling the study. Remember that the researcher is an observer, not an influencer.<\/p>\r\n<\/section>\r\n<section class=\"textbox tryIt\">[ohm2_question hide_question_numbers=1]14021[\/ohm2_question]<\/section>\r\n<section class=\"textbox tryIt\">[ohm2_question hide_question_numbers=1]3261[\/ohm2_question]<\/section>\r\n<section><\/section>","rendered":"<section class=\"textbox learningGoals\">\n<ul>\n<li>Recognize observational studies and list the key components<\/li>\n<li>Describe confounding factors that may influence an association<\/li>\n<\/ul>\n<\/section>\n<h2>Observational Studies<\/h2>\n<p>In an <strong>observational study<\/strong>, a researcher will observe an outcome without interfering. Instead of trying to assess cause and effect, an observational study is typically used when the goal is to learn about characteristics of a population or to compare groups within a population with respect to some characteristic. Sometimes observational studies are used because they might be the only way certain types of questions can be studied.<\/p>\n<p>When designing an observational study, researchers are often looking for a relationship between two variables.<\/p>\n<section class=\"textbox keyTakeaway\">\n<h3>explanatory variable (factor of interest)<\/h3>\n<p>The <strong>explanatory variable<\/strong> is the independent variable that is of interest to the researcher.<\/p>\n<\/section>\n<p>The explanatory variable is what researchers change or select to see how it affects something else; it&#8217;s the &#8220;cause&#8221; or input that helps explain why an outcome happens.\u00a0<\/p>\n<section class=\"textbox keyTakeaway\">\n<h3>response variable (response factor)<\/h3>\n<p>The <strong>response variable<\/strong> is the dependent variable that allows the researcher to objectively compare the differences.<\/p>\n<\/section>\n<p>The response variable is what researchers measure to see if it changes based on the explanatory variable; it&#8217;s the outcome or result being studied.\u00a0<\/p>\n<section class=\"textbox example\" aria-label=\"Example\">\n<ul>\n<li>Hours of sleep (explanatory variable) might explain test scores (response variable)<\/li>\n<li>Amount of rainfall (explanatory variable) might explain crop yields (response variable)<\/li>\n<\/ul>\n<\/section>\n<p>In observational studies, researchers can only observe and measure what naturally occurs; they cannot assign participants to different groups, control the conditions, or isolate specific variables like they would in an experiment. Due to a lack of control, observational studies may inherently be at risk of containing <strong>confounding<\/strong> biases, which are outside of the control of the researcher.\u00a0<\/p>\n<section class=\"textbox keyTakeaway\">\n<h3>confounding variable<\/h3>\n<p>A confounding variable is a variable that was not accounted for in a study and may actually influence other variables in the study.<\/p>\n<\/section>\n<section class=\"textbox proTip\">\n<p>An observational study can show an association<em>\u00a0<\/em>between variables, but it cannot establish a cause-and-effect relationship since the researchers are not controlling the study. Remember that the researcher is an observer, not an influencer.<\/p>\n<\/section>\n<section class=\"textbox tryIt\"><iframe loading=\"lazy\" id=\"ohm14021\" class=\"resizable\" src=\"https:\/\/ohm.one.lumenlearning.com\/multiembedq.php?id=14021&theme=lumen&iframe_resize_id=ohm14021&source=tnh\" width=\"100%\" height=\"150\"><\/iframe><\/section>\n<section class=\"textbox tryIt\"><iframe loading=\"lazy\" id=\"ohm3261\" class=\"resizable\" src=\"https:\/\/ohm.one.lumenlearning.com\/multiembedq.php?id=3261&theme=lumen&iframe_resize_id=ohm3261&source=tnh\" width=\"100%\" height=\"150\"><\/iframe><\/section>\n<section><\/section>\n","protected":false},"author":13,"menu_order":4,"template":"","meta":{"_candela_citation":"[]","pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"part":743,"module-header":"learn_it","content_attributions":[],"internal_book_links":[],"video_content":null,"cc_video_embed_content":{"cc_scripts":"","media_targets":[]},"try_it_collection":null,"_links":{"self":[{"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/pressbooks\/v2\/chapters\/758"}],"collection":[{"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/wp\/v2\/users\/13"}],"version-history":[{"count":16,"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/pressbooks\/v2\/chapters\/758\/revisions"}],"predecessor-version":[{"id":7041,"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/pressbooks\/v2\/chapters\/758\/revisions\/7041"}],"part":[{"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/pressbooks\/v2\/parts\/743"}],"metadata":[{"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/pressbooks\/v2\/chapters\/758\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/wp\/v2\/media?parent=758"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/pressbooks\/v2\/chapter-type?post=758"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/wp\/v2\/contributor?post=758"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/content.one.lumenlearning.com\/introstatstest\/wp-json\/wp\/v2\/license?post=758"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}