Chapter 14 - Healthcare Statistics Flashcards
ratio
a calculation that compares two quantities found by dividing one quantity by another
Consider a class that has 20 male students and 80 female students. We can think about this in several ways. We could express this simply as the ratio of men to women and write the relationship as 20:80 or 20/80. We can also simplify this by dividing both the numerator and the denominator by a number that divides evenly into both the numerator and the denominator. In this case, we could divide both by 20 to simplify this to a 1:4 ratio (or 1/4 ratio). This indicates that for every man, there are four women.
We could also consider this from the inverse perspective, i.e., the number of women relative to the number of men; in this case the ratio of women to men is 80/20 which is equivalent to 4 to 1, i.e., there are four women for every man.
proportion
A proportion is a type of ratio that relates a part to a whole. For example, in the class with with 20 men and 80 women, the total class size is 100, and the proportion of men is 20/100 or 20%. The proportion of women is 80/100 or 80%. In both of these proportions the size of part of the class is being related to the size of the entire class.
rate
Rates are a special type of ratio that incorporate the dimension of time into the denominator. Familiar examples include measurements of speed (miles per hour) or water flow (gallons per minute).
Example #1:
If a car travels 24 miles in 2 hours, its average speed is a rate of 24 miles/ 2 hours = 12 miles/hr.
mortality rate
also called death rate
the proportion of deaths occurring over a span of time in a population
attack rate
the proportion of people developing an infectious disease after exposure to a pathogen
case-fatality rate
the proportion of individuals who die after developing a disease
autopsy rate
the number of deaths receiving an autopsy per all deaths, usually expressed per 100 deaths
birth rate
the proportion of births to the total population in a place in a given time, usually expressed as a quantity per 1000 of population
proportionate mortality rate
The proportion of deaths in a specified population over a period of time attributable to different causes. Each cause is expressed as a percentage of all deaths, and the sum of the causes must add to 100%.
postneonatal
of, relating to, or affecting the human infant during the period between approximately the first month after birth and the end of the first year of life
race-specific mortality rate
A mortality rate related to a specified racial group. Both numerator and denominator are limited to the specified race.
death-to-case ratio
Number of deaths assigned to a specific cause during a given time interval.
neonatal mortality rate
number of deaths among children from just after birth to under 1 month of age
inpatient service day (IPSD)
A unit of measure that reflects the services received by one inpatient during a 24-hour period.
crude death rate
also called crude mortality rate
The total number of deaths in a given population for a given period of time divided by the estimated population for the same period of time.
gross death rate (hospital)
The number of inpatient deaths that occurred during a given time period divided by the total number of inpatient discharges, including deaths, for the same time period.
cause-specific mortality rate
The rate of death due to a specified cause
census
- the number of inpatients present in a healthcare facility at any given time
- an official count or survey of a population, typically recording various details of individuals
consultation rate
The total number of hospital inpatients receiving consultations for a given period divided by the total number of discharges and deaths for the same period.
average daily census (hospital)
The mean number of hospital inpatients present in the hospital each day for a given period of time.
case mix
- A description of a patient population based on any number of specific characteristics, including age, gender, type of insurance, diagnosis, risk factors, treatment received, and resources used
- The distribution of patients into categories reflecting differences in severity of illness or resource consumption
case-mix index (CMI)
The average relative weight of all cases treated at a given facility or by a given physician, which reflects the resource intensity or clinical severity of a specific group in relation to the other groups in the classification system; calculated by dividing the sum of the weights of diagnosis-related groups for patients discharged during a given period by the total number of patients discharged
stillbirth vs miscarriage
A stillbirth is the death or loss of a baby before or during delivery. Both miscarriage and stillbirth describe pregnancy loss, but they differ according to when the loss occurs. In the United States, a miscarriage is usually defined as loss of a baby before the 20th week of pregnancy, and a stillbirth is loss of a baby at or after 20 weeks of pregnancy.
Stillbirth is further classified as either early, late, or term.
An early stillbirth is a fetal death occurring between 20 and 27 completed weeks of pregnancy.
A late stillbirth occurs between 28 and 36 completed pregnancy weeks.
A term stillbirth occurs between 37 or more completed pregnancy weeks.
occasion of service
A specified identifiable service involved in the care of a patient that is not an encounter (for example, a lab test ordered during an encounter).
encounter (hospital)
The face-to-face contact between a patient and a provider who has primary responsibility for assessing and treating the condition of the patient at a given contact and exercises independent judgment in the care of the patient.
vital statistics
quantitative data concerning the population, such as the number of births, deaths, migrations, fetal deaths, marriages and divorces
A Gantt chart is a type of bar chart that illustrates a project schedule. This chart lists the tasks to be performed on the vertical axis, and time intervals on the horizontal axis. The width of the horizontal bars in the graph shows the duration of each activity.
Gantt charts illustrate the start and finish dates of the terminal elements and summary elements of a project. Terminal elements and summary elements constitute the work breakdown structure of the project. Modern Gantt charts also show the dependency relationships between activities. Gantt charts can be used to show current schedule status using percent-complete shadings and a vertical “TODAY” line.
Gantt charts are usually created initially using an early start time approach, where each task is scheduled to start immediately when its prerequisites are complete. This method maximizes the float time available for all tasks.
float
also called float time or slack
It is the amount of time that a task in a project network can be delayed or extended without causing a delay to either subsequent tasks or the project completion date.
The amount of time a task can be delayed or extended without causing a delay to a subsequent task is called “free float”.
The amount of time a task can be delayed or extended without delaying the project finish date or violating a schedule constraint is called “total float”.
net death rate (hospital)
It is an adjusted death rate. It is calculated with the assumption that certain deaths should not count against the hospital. The net death rate is an adjusted rate because it does not include patients who die within 48 hours of admission.
The reason for excluding these deaths is that historically it has been believed that 48 hours is not enough time to positively affect patient outcome. In other words, the patient was not admitted to the hospital in a manner timely enough for treatment to have an effect on his or her outcome.
A&C
acronym for adults and children
NB
acronym for newborn
fetal death
a fetus who is spontaneously expelled from the uterus at any time during the pregnancy
population-based statistics
Statistics based on a defined population rather than on a sample drawn from the same population.
prevalence rate
The proportion of people in a population who have a particular disease at a specific point in time or over a specified period of time.
average daily census
The mean number of hospital inpatients present in the hospital each day for a given period of time.
four main relationships in Gantt charts
In Gantt charts, there are four main relationships between sequential tasks:
To make the below easier to read, think of it like this:
(preceding task condition) to (current task condition) [acronym]
Start to Start (SS) – SS tasks can’t start until a preceding task starts.
Finish to Start (FS) – FS tasks can’t start until a preceding task is finished.
Start to Finish (SF) – SF tasks can’t finish until a preceding task starts.
Finish to Finish (FF) – FF tasks can’t finish until a preceding task is finished.
In this relationship, what the current task is able to do always depends on what the preceding task is doing or has done.
terminal elements vs summary elements (Gantt chart)
Terminal elements are the smaller more intricate tasks that need to be completed as part of a larger task. A summary element is made up of terminal elements to form the larger task.
For example, a summary element for a car manufacturer would be to paint the vehicle. The terminal elements of painting the vehicle would be to strip any original paint, primer, apply your first, second and top coats, and finally, wash, wax and buff the new paint job. Once the terminal and summary elements are defined, a manager can then add projected and actual projection for completion of each of those elements.
