I don't know if this is what you are looking for so I am not putting it as an answer in hopes someone else will chime in.
In scientific studies a horizontal study is when you study something happening at a certain time (or at the same, or about the same time). Like seeing how many people are overweight now and how many have heart attacks now.
A vertical study is when you study the same thing over time. Like the Framingham Heart Study, you find a group people and study how things happen to them over many years. Sometimes the group you study is a particular group to see how that group with certain criteria develops. (Maybe you study people who lived within 50 miles or Chernobyl) Sometimes the group is random and representative of a population.
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A vertical study is when you study the same thing over time. Like the Framingham Heart Study, you find a group people and study how things happen to them over many years. Sometimes the group you study is a particular group to see how that group with certain criteria develops. (Maybe you study people who lived within 50 miles or Chernobyl) Sometimes the group is random and representative of a population.