Guided Notes

Descriptive Statistics for Healthcare Data

Mean, median, percentiles, standard deviation, distributions and skew — summarizing length of stay, costs, wait times and lab values correctly.

Center: mean vs median

Slide 1 / 5

• Mean = sum ÷ count. Sensitive to extreme values. • Median = middle value when sorted. Robust to outliers. Example LOS (days): 2, 2, 3, 3, 4, 5, 41 → mean 8.6, median 3. One very long stay pulls the mean far above what's typical. For LOS, costs and wait times, report the median (and percentiles); use the mean when you need totals (budgets).

← Data Quality & Validation