Patient selection: infertile male
Outcome: karyotype analysis
Parameters:
(1) serum LH, presumably IU/L
(2) mean testis volume in mL (presumable average of left and right testis volume)
(3) sperm concentration in million per mL
points for LH =
= MIN(100,3.333*(LH))
points for mean testis volume =
= MAX(0,-0.48*(volume))
points for sperm concentration =
= MIN(0,-0.55*(sperm count in 10^6/L))
total score =
= SUM(points for all 3 parameters)
Interpretation:
• minimum score: 0
• maximum score: 167
• The authors used 2% for threshhold to do testing since the negative predictive value was 99%. This corresponds to a score of 58.
• A cutoff of 5% had a better Youden score (39% vs 27%). This corresponds to a score of 78.
|
Total Score
|
Percent Karyotype Abnormality
|
|
<= 44
|
< 1%
|
|
44 to 167
|
(0.00644 * ((points)^2)) - (0.6604 * (points)) + 17.49
|
