Table 3.
Results of receiver operating curve (ROC) analyses for serum folate levels with suicidal behavior.
| Suicidal behavior | Area under ROC | Optimal cut-offs for serum folate levels | By optimal cut-offs | By folate deficiency (<3 ng/mL) | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Sensitivity % | Specificity % | Positive predictive value % | Negative predictive value % | Sensitivity % | Specificity % | Positive predictive value % | Negative predictive value % | |||
| Present previous suicidal attempt | 0.684 | 6.15 | 70.2 | 63.3 | 23.4 | 93.9 | 94.8 | 17.7 | 20.5 | 92.1 |
| Higher baseline suicidal severity | 0.624 | 6.25 | 65.4 | 59.4 | 43.2 | 70.5 | 95.8 | 11.2 | 51.3 | 68.3 |
| Increased suicidal severity during follow-up | 0.649 | 6.05 | 67.5 | 57.9 | 32.1 | 85.2 | 94.0 | 12.3 | 26.2 | 83.2 |
| Fatal/non-fatal suicidal attempt during follow-up | 0.768 | 5.95 | 80.1 | 74.4 | 12.9% | 97.8 | 94.1 | 18.4 | 13.8 | 96.5 |
Baseline suicidal severity was defined using the Brief Psychiatric Rating Scale (BPRS) suicidality item scores, divided into lower [1 (not present)~3 (mild)] and higher [4 (moderate)~7 (extremely severe)]. Increased suicidal severity was defined as any instance in the increase in BPRS suicidality item score during 12-month pharmacotherapy.