Biostatistics involves the collection, analysis, interpretation and reporting of data related to medicine and public health. It plays an important role in determining and assessing risk factors for disease, and testing new treatments. For example, survival analysis is a statistical model of time-to-outcome or time-to-event data. For example, if we are looking at the effect of new intervention (this would be the new variable), the time between the introduction of the variable (i.e. the start of the new intervention) and any potential event occurring is survival analysis.
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