Polyarteritis Nodosa: ['A necrotizing vasculitis that affects medium-sized arteries, it is usually idiopathic, and may be triggered by viral infections (Hepatitis B, also others). A multisystem disease, it most commonly affects skin (nodules, livedo reticularis) and peripheral nerves; higher morbidity is associated with gastrointestinal, central nervous system, cardiac, and/or other organ involvement. Anti-neutrophil cytoplasmic antibodies (ANCA) are typically negative. [ NCI ]']
In this example the number of individuals is 2, since only 2 unique individuals (FG1 and FG2) have EXAMPLE_ENDPOINT events.
Number of individuals
123
79
44
?
Unadjusted prevalence
Using example data:
ID
phenocode
age
FG1
EXAMPLE_ENDPOINT
45
FG1
ENDPOINT_XYZ
46
FG1
DEATH
47
FG2
EXAMPLE_ENDPOINT
30
FG2
EXAMPLE_ENDPOINT
30.1
FG3
ENDPOINT_XYZ
50
In this example the unadjusted prevalence is 66 %.
The unadjusted prevalence is the number of individuals having an endpoint divided by the total number of individuals.
Here:
2 unique individuals (FG1 and FG2) have EXAMPLE_ENDPOINT events
1 individual (FG3) has no EXAMPLE_ENDPOINT event
So the unadjusted prevalence is 2 / 3 = 66 %.
Unadjusted prevalence (%)
0.07
0.08
0.06
?
Mean age at first event
Using example data:
ID
phenocode
age
FG1
EXAMPLE_ENDPOINT
45
FG1
ENDPOINT_XYZ
46
FG1
DEATH
47
FG2
EXAMPLE_ENDPOINT
30
FG2
EXAMPLE_ENDPOINT
30.1
FG3
ENDPOINT_XYZ
50
In this example the mean age at first event is 37.5.
The mean age at first event for EXAMPLE_ENDPOINT is computed by:
selecting individuals having EXAMPLE_ENDPOINT: FG1 and FG2
for these individuals, taking the age of their first event of EXAMPLE_ENDPOINT: 45 for FG1 and 30 for FG2
computing the mean of these values
So the mean age at first event is Mean(45, 30) = 37.5.
Mean age at first event (years)
49.2
48.51
50.45
?
Case fatality at 5 years
Using example data:
ID
phenocode
age
FG1
EXAMPLE_ENDPOINT
45
FG1
ENDPOINT_XYZ
46
FG1
DEATH
47
FG2
EXAMPLE_ENDPOINT
30
FG2
EXAMPLE_ENDPOINT
30.1
FG3
ENDPOINT_XYZ
50
In this example the case fatality at 5 years is 50%.
The case fatality at 5 years is computed by:
selecting individuals with EXAMPLE_ENDPOINT events: FG1 and FG2.
for each of them, checking if they have a DEATH event: FG1 has this event.
checking the number of individuals for which 5 years or less happened between the first event of EXAMPLE_ENDPOINT and the DEATH event: only 1 (FG1, with 47 - 25 = 2 years between said events).
Here only 1 individual has less than 5 years between EXAMPLE_ENDPOINT and DEATH, and 2 individuals have EXAMPLE_ENDPOINT. The case fatality at 5 years is 1 / 2 = 50 %.
Case fatality at 5-years (%)
9.76
7.59
13.64
Longitudinal metrics
Sex
All
Female
Male
?
Median number of events per individual
Using example data:
ID
phenocode
age
FG1
EXAMPLE_ENDPOINT
45
FG1
ENDPOINT_XYZ
46
FG1
DEATH
47
FG2
EXAMPLE_ENDPOINT
30
FG2
EXAMPLE_ENDPOINT
30.1
FG3
ENDPOINT_XYZ
50
In this example the median number of events is 1.5.
The median number of events is computed by:
selecting individuals with EXAMPLE_ENDPOINT: FG1, FG2
counting the number of EXAMPLE_ENDPOINT events for each of these individuals:
1 event for FG1
2 events for FG2
computing the median of these values.
Here the median number of events per individual is Median(1, 2) = 1.5.
Median nb. of events per indiv.
1
1
1
?
Recurrence within 6 months
Using example data:
ID
phenocode
age
FG1
EXAMPLE_ENDPOINT
45
FG1
ENDPOINT_XYZ
46
FG1
DEATH
47
FG2
EXAMPLE_ENDPOINT
30
FG2
EXAMPLE_ENDPOINT
30.1
FG3
ENDPOINT_XYZ
50
In this example the recurrence within 6 months is 50 %.
The recurrence within 6 months is computed by:
selecting individuals with EXAMPLE_ENDPOINT: FG1, FG2, so 2 individuals in total.
for each of them, checking if they have 2 events of EXAMPLE_ENDPOINT less than 6 months apart:
FG1 has only 1 event of EXAMPLE_ENDPOINT so FG1 is discarded.
FG2 has 2 events of EXAMPLE_ENDPOINT less than 6 months apart (one at age 30 and the other at age 30.1).
counting the number of individuals with events less than 6 months apart: 1 in this case (FG2)
Here the recurrence within 6 months is 1 / 2 = 50 %.