van Straalen et al reported a model for identifying a patient with juvenile idiopathic arthritis (JIA). This can help to distinguish it from chronic musculoskeletal pain. The authors are from Children's Hospital of the University of Utrecht.
Parameters:
(1) sex
(2) age at first visit in years, from 0 to 18
(3) difficulty placing hands behind neck
(4) difficult looking over shoulder
(5) painful or swollen neck
(6) painful or swollen shoulder
(7) painful or swollen hip
(8) painful or swollen knee
(9) painful or swollen ankle
(10) skin rash
(11) VAS scale for disease activity, from 0 to 10
(12) difficulty with self-care
(13) depressed or feeling sad
points for age =
= 100 - (5.556 * (age))
points for disease activity with VAS scale =
= 2.19 * (VAS score)
Parameter |
Finding |
Points |
sex |
female |
0 |
|
male |
24.6 |
hands behind neck |
no |
3.1 |
|
yes |
0 |
looking over shoulder |
no |
5.3 |
|
yes |
0 |
painful/swollen neck |
no |
22.6 |
|
yes |
0 |
shoulder |
no |
0 |
|
yes |
27.3 |
hip |
symmetric |
0 |
|
asymmetric |
9.7 |
|
none |
32.6 |
knee |
symmetric |
0 |
|
asymmetric |
41.4 |
|
none |
14.4 |
ankle |
yes |
0 |
|
no |
13.8 |
skin rash |
no |
0 |
|
yes |
23.2 |
difficulty self-care |
no |
0 |
|
yes |
28.2 |
depressed or sad |
no |
6 |
|
yes |
0 |
total score =
= SUM(points for all of the parameters)
Interpretation:
• minimum score: 0
• maximum score: 349
value of X =-
= (0.03078 * (score)) - 4.402
probability of JIA =
= 1 / ( 1 + EXP((-1) * X))
Performance:
• The area under the ROC curve is 0.83.
Specialty: Immunology/Rheumatology