Data Analytics & Use
Health data only creates value when it is turned into information. This domain tests healthcare statistics, rate calculations, and data presentation — the ability to compute standard hospital measures correctly and display them so decision-makers can act.
Healthcare statistics and rate formulas
You must know the standard hospital rates. Gross death rate = inpatient deaths ÷ discharges (including deaths) × 100; net death rate excludes deaths within 48 hours of admission. Average length of stay (ALOS) = total discharge days ÷ number of discharges. Other common measures include the cesarean-section rate, the nosocomial (hospital-acquired) infection rate, and the autopsy rate. Pay attention to whether the denominator uses admissions, discharges, or patient days — choosing the wrong denominator is the most common error.
Case-mix index and data interpretation
The case-mix index (CMI) is the average MS-DRG relative weight: the sum of the relative weights of all discharges divided by the number of discharges. A rising CMI signals a more severe, resource-intensive patient population and typically higher reimbursement; an unexpected drop may indicate a coding or documentation problem worth investigating. Analysts also work with measures of central tendency (mean, median, mode) and recognize that the median is more appropriate than the mean when outliers (very long stays) skew the data.
Presenting data effectively
Choosing the right display is part of analytics. Line graphs show trends over time; bar charts compare discrete categories; pie charts show parts of a single whole; histograms show the frequency distribution of a continuous variable; and scatter plots show the relationship between two variables. Good visualizations use clear titles, labeled axes, and appropriate scales so the audience draws the intended conclusion without distortion.