The validity of rapid test to detect prostate-specific antigen (PSA) in seminal fluid

Background: this study was conducted to determine whether the rapid test device can be used to detect psa in seminal fluid specifically, for solving sexual assault cases. methods: a cross sectional study has been conducted. a total of 45 samples were taken consecutively. semen was diluted in serially up to 1:5.000.000 and male urin up to 1:200 using distilled water, whereas female urin was not diluted. samples were analyzed using rapid test psa. results: the proportion of positive results of psa in seminal fluid, male urin and female urin respectively was 100%, 6.67%, and 0%. statistically, these differences are highly significant. the analysis revealed that the psa rapid test device was 100% sensitive and 96.67% specific to detect seminal fluid. the test also have ppv 93.75%, npv 100%, lr(+) 33.33, lr(-) 0, and auc 0.983. conclusion: psa rapid test is very specific and sensitive to detect psa in seminal fluid. therefore, this device is suggested for forensic use in sexual assault cases. (med j indones 2011; 20:278-82)