Title: When a study can’t be replicated | Science News for Students
Headings: When a study can’t be replicated
Science & Society
When a study can’t be replicated
Many factors can prevent scientists from repeating research and confirming results
By Janet Raloff
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Content: Some investigators have concluded that it may be next to impossible to redo a study exactly. This can be true especially when a study works with subjects or materials that vary greatly. Cells, animals and people are all things that have a lot of variation. Due to genetic or developmental differences, one cell or individual may respond differently to stimuli than another will. Stimuli might include foods, drugs, infectious germs or some other aspect of the environment. Similarly, some studies involve conditions that are quite complicated. Examples can include the weather or how crowds of people behave. Consider climate studies. Computers are not yet big enough and fast enough to account for everything that affects climate, scientists note. Many of these factors will vary broadly over time and distance.