Hospital Statistics Basic Formulae Formulas for commonly computed healthcare rates and percentages used on the RHIT and RHIA examination Calculating Rates The basic formula for calculating rates is the number of times something actually happened/the number of times it could have happened. Measures of Central Tendency Mean: ( ) = ℎ ℎ Median: The midpoint (center) of the distribution of values, or the point above and below which 50 percent of the values fall. The median is a data point on the number line. Mode: The value that occurs most frequently in the data. The mode appears as a data point on the number line. Variance: 2 = Σ(X − ̅) 2 − 1 Standard Deviation: = √ ∑( X − x̄) (N − 1) Calculating Census Average Daily Census: ℎ ℎ ℎ Average Daily Newborn Census: ℎ Average Daily Census for a Patient Care Unit: ℎ ℎ ℎ Occupancy Rates Bed Occupancy Ratio: ℎ ( × ℎ ) × 100 Newborn Bassinet Occupancy Ratio: × ℎ × 100 Bed Turnover Rate: Direct: ℎ ( ℎ ) ℎ Indirect: × ℎ Length of Stay Average Length of Stay: ℎ ( ℎ ) ℎ ( ℎ ) Average Newborn Length of Stay: ℎ ℎ ( ℎ ) Death Rates Gross (Hospital) Death Rate: ℎ ( ) ℎ ( & ℎ ) ℎ × 100 Net Death Rate/Institutional Death Rate: ℎ ( ) ℎ < 48 ℎ ℎ ( ℎ ) ℎ < 48 ℎ ℎ × 100 Postoperative Death Rate: ℎ ( ℎ 10 ) ℎ ℎ × 100 Anesthesia Death Rate: ℎ ℎ ℎ × 100 Maternal Death Rate: ℎ ℎ ( ℎ ) ℎ × 100 Newborn Mortality Rate: ℎ ℎ ( ℎ ) ℎ × 100 Vital Statistics—Newborn Neonatal Mortality Rate: ℎ ℎ ℎ × 1,000 Infant Mortality Rate: ℎ ( ) ℎ ℎ × 1,000 Fetal Death Rate: ⁄ ℎ ℎ + ℎ ℎ × 100 Cancer Mortality Rate: ℎ × 100 Autopsy Rates Gross Autopsy Rate: ℎ ℎ ℎ × 100 Net Autopsy Rate: ℎ ℎ − ′ ′ × 100 Adjusted Hospital Autopsy Rate: ℎ ℎ ℎ ℎ × 100 Newborn Autopsy Rate: ℎ ℎ × 100 Fetal Autopsy Rate: ℎ ℎ ℎ × 100 Morbidity and Miscellaneous Infection Rate: ℎ ( ℎ ) ℎ × 100 Postoperative Infection Rate: ℎ × 100 Cesarean Section Rate: − ℎ ( − ) × 100 Consultation Rate: ℎ × 100 HIM Department Statistics Completed Work: = − Labor Productivity: = Case-Mix Index: ℎ ℎ − ℎ ℎ
