The Hawthorne effect is a phenomenon in research where a change in a subject's behaviour occurs simply because they are aware of being studied or observed, rather than due to any specific manipulation or intervention introduced by the researchers. This effect was first observed during a series of industrial experiments conducted at the Hawthorne Works factory of Western Electric in the 1920s and 1930s, where researchers found that workers' productivity increased not only in response to changes in working conditions (like lighting) but also when changes were reversed or even when no changes were made, seemingly because the workers were aware they were being observed and were responding to the attention they were receiving. The Hawthorne effect poses a challenge for researchers as it can confound the results of studies if participants' awareness of being studied influences their behaviour in unintended ways, making it difficult to determine the true effect of the independent variable. Researchers often try to minimise the Hawthorne effect through various methodological strategies, such as using blind or double-blind study designs or by observing participants unobtrusively.