Vital signs are important indicators of a patient's health status and can be good predictors in healthcare machine learning models (Sahni et al., 2018). Vital signs are typically taken at every patient visit, so they can easily be included in their raw (numerical) form to preserve granularity.

In the following screenshot of the table, we notice that while height and weight are present, the body mass index (BMI) is missing. We will demonstrate the calculation of the BMI in Chapter 5, Computing Foundations – Introduction to Python. Second, Visit #10004 is missing a temperature reading. This is common in healthcare and may be caused by an oversight in care:

Later in the chapter, we will impute the normal temperature for this visit.