8A_Diagnosis_Pleno 3.pptx.pdf

Semen PSA & AP Testing
for Sexual Assault
EBM 8A
Alya Faizah (2006567503)
Cokorda Istri Agung Dewinta Adnyani
(2006468213)
Diski Saisa (2006567693)
Josh Nathaniel J
Khaura Tsabitha ( 2006533396)
Tutor - dr. Oktavinda Saﬁtry, Sp.F MPdKed

Clinical Scenario
The incidence of rape cases has increased in Brazil. These increases in numbers are more evident in metropolitan
areas such as São Paulo. According to studies conducted in Brazil, the majority of cases like this are done by relatives
and people close to the victim. This has made the crime more difficult to denounce, as only 10% of the cases are
reported to competent police authorities. Usually crimes like this uses cytological exams to confirm suspicion of
rape. But, one difficulty found in using cytological exams is that spermatozoa is not always detected. The absence of
spermatozoa in specimens collected from rape victims could happen due to several factors such as the agressor is
suffering azoospermia or has undergo a successful vasectomy. Because of these phenomena, confirming rape cases
with absence of spermatozoa has been difficult.
The same goes with this particular case of subject X. A 25 year old female, Subject X, was found dead in the streets
of São with bruses, blood stains and naked bottom. After conducting investigation and autopsy of the subject,
findings suggested that there were multiple sharp force injuries and indications of sexual assault. To confirm the
suspicions, vaginal swabs were taken from the subject to be examined with cytological exams. Results show an
absence of spermatozoa from the specimen. The report suggests the use of PSA test kit and AP test kit in addition
to conventional sperm smear for investigation as confirmatory tests to better provide specific and sensitive
information about the case.

According to Indonesia National Commission on Violence Against Women, In 2020, Sexual assault is the
second most common violence case to woman in Indonesia. It took 21% of all cases or about 1.731 cases.
In sexual assault crimes, the exchange of biological material, such as hair and bodily fluids, can occur if
physical contact is involved. Thus, indicating the presence of biological material in the victim's body is
essential to define the crime committed.
Currently, the gold standard of forensic analysis of sexual assault s is spermatozoa examination.
Spermatozoa examination is based on light microscopy. Finding spermatozoa in sexual assault is a difficult
task because the sperm cell could lose its characteristics of “tadpole” morphology. Spermatozoa examination
is also time-consuming which requires 5-7 hours to analyze.
Other than spermatozoa examination, Acid phosphatase (AP) and Prostate-specific antigen (PSA) test also
can be used in rape cases as been proven before. AP activity uses for screening or presumptive tests because
of its sensitivity and specificity that can be detected up to 72 hours post-coitus in the vagina. PSA test use as
confirmatory test because for up to 48 hours post-coitus it still persists at detectable levels.
In Indonesia, PSA test kits and AP test kits are still rarely used in such cases. This study aims to provide
evidence of the sensitivity, specificity, and diagnostic evidence to confirm its applicability to diagnose sexual
intercourse in sexual assault cases
Introduction

Clinical Question & PICO
Women Patient in
suspicion of sexual
assault
Patient
01
PSA and AP testing
Intervention
02
Sperm detection
microscopy
Comparison
03
Sensitivity, AUC,
Specificity
Outcome
04
Clinical Question
Can PSA and AP testing be used to confirm
sexual assault offenses in comparison to
sperm detection?

Keyword Analysis
Patient/Problem Intervention Control Outcome
Keyword Sexual assault PSA testing
AP testing
Sperm detection
microscopy
Sensitivity,
Specificity, and
AUC
Synonyms ● Sex offences,
● Rape,
● Sexual Abuse,
● Sexual violence
● Prostate
Specific
Antigen
(PSA)
● Acid
Phosphatase
(AP)
● Spermatozo
a
● Diagnosis

Methods - Search strategy
Pubmed | Cochrane
Medline | Scopus I EMBASE
Search Databases
Inclusion
● Studies included are systematic review of observational
epidemiological study design (Case Series, Cohort, Cross Sectional)
OR diagnostic tests
● Studies must include rape/sexual assault cases
● Studies are controlled with sperm/spermatozoa microscopic test
● Measurement outcome should be positive and negative outcome
with conﬁrmatory test results
Exclusion
● Incomplete Data Report
● Unretrievable full text
● Non-english studies
Study selection
Type : Diagnosis
Study Design:
1. Systematic Review of
Cross Sectional Study
2. Cross Sectional Study
Level of Evidence and
Type of Study

Results - searching
Database name Search strategy Hits Selected
articles
MEDLINE ((sensitivity OR specificity OR detection OR diagnosis OR ROC OR AUC) AND
(acid phosphatase OR ap) OR (prostate specific antigen OR psa OR psa
test)) AND (sexual harassment OR sexual violence OR rape OR sex violence
OR sexual trauma OR sex abuse OR domestic violence )
189 8
Scopus ( ( sexual ) AND ( assault OR violent OR abuse ) ) AND ( psa OR "prostate
specific antigen" OR "prostate-specific antigen" OR "PSA test" ) OR ( "Acid
Phosphatase" OR "AP test" ) AND ( ( diagnosis OR diagnostic OR "diagnostic
value" OR specificity OR sensitivity OR "area under curve" OR auc OR
"receiver operating characteristic" OR roc ) )
186 6

Database
name
Search strategy Hits Selected
articles
Cochrane (Sexual assault OR Sex offences OR Rape OR Sexual Abuse OR Sexual violence)
AND (Prostate Specific Antigen OR PSA OR Acid Phosphatase OR AP) AND
(Sensitivity OR Specificity OR ROC OR AUC)
10 0
EMBASE ('sexual assault'/exp OR 'sexual assault' OR (sexual AND ('assault'/exp OR
assault)) OR 'sex offences' OR (('sex'/exp OR sex) AND offences) OR 'rape'/exp
OR rape OR 'sexual abuse'/exp OR 'sexual abuse' OR (sexual AND ('abuse'/exp OR
abuse)) OR 'sexual violence'/exp OR 'sexual violence' OR (sexual AND
('violence'/exp OR violence))) AND ('prostate specific antigen'/exp OR 'prostate
specific antigen' OR (('prostate'/exp OR prostate) AND specific AND
('antigen'/exp OR antigen)) OR psa OR 'acid phosphatase'/exp OR 'acid
phosphatase' OR (('acid'/exp OR acid) AND ('phosphatase'/exp OR phosphatase))
OR ap) AND ('sensitivity'/exp OR sensitivity OR 'specificity'/exp OR specificity OR
roc OR 'auc'/exp OR auc)
58 6
PubMed ('sexual assault'/exp OR 'sexual assault' OR (sexual AND ('assault'/exp OR
assault)) OR 'sex offences' OR (('sex'/exp OR sex) AND offences) OR 'rape'/exp
OR rape OR 'sexual abuse'/exp OR 'sexual abuse' OR (sexual AND ('abuse'/exp OR
abuse)) OR 'sexual violence'/exp OR 'sexual violence' OR (sexual AND
('violence'/exp OR violence))) AND ('prostate specific antigen'/exp OR 'prostate
specific antigen' OR (('prostate'/exp OR prostate) AND specific AND
('antigen'/exp OR antigen)) OR psa OR 'acid phosphatase'/exp OR 'acid
phosphatase' OR (('acid'/exp OR acid) AND ('phosphatase'/exp OR phosphatase))
OR ap) AND ('sensitivity'/exp OR sensitivity OR 'specificity'/exp OR specificity OR
138 4

Critical Appraisal Result
EBM 8A
● Alya Faizah (2006567503)
● Cokorda Istri Agung Dewinta Adnyani
(2006468213)
● Diski Saisa (2006567693)
● Josh Nathaniel J (2006522726)
● Khaura Tsabitha ( 2006533396)
Tutor - dr. Oktavinda Saﬁtry, Sp.F MPdKed

Author Patient Group Outcome Key results
Peonim et al,. (2013), J Forensic Leg Med,
Thailand [1]
2450 vaginal swabs from raped women
was examined using 3 methods acid
phosphatase (AP) activity, prostate
specific antigen (PSA) detection, and
spermatozoa examination.
1. Sensitivity
2. Specificity
3. ROC
1. Sensitivity of AP test is 65.5%, PSA test is
80.4% and AP-PSA is 84.5%
2. Specificity of AP test is 96.4%, PSA test
is 92.3% and AP-PSA test is 91.9%
3. ROC area of AP test is 0.8091, PSA test
is 0.8639, and AP-PSA test is 0.8823. ROC
area of the AP-PSA was significantly
greater than both the tests individually.
Suttipasit., et al (2018), J Forensic Leg
Med, Thailand
114 female victims raped by men.
Samples from subjects are then tested
using sperm test, PSA test and Sg test.
1) determine the persistence of each
marker
2) determine their detection rates,
comparing all three over specific time
intervals
3) compare the PSA test and the Sg test
performance when the sperm test is
positive or negative over time
4) determine the order of priority for
running these screening tests
1) sperm had the longest persistence
2) sperm had the highest detection rate
3) detection rate of the Sg test was
significantly better than that of the PSA
test overall
4) the order of priority of the tests are
sperm detection, Sg test, and PSA test
Khaldi et al, (2004), J Forensic Sci
Cohort Selection
227 anonymous sample were divided
into four groups (normospermia,
oligospermia, azoospermia, and
controls).
the samples were then analyse and
were subjected to three fast detection
semen tests: Diff-Quick fast coloration,
AP detection, and PSA detection
Discover whether spermatozoa
concentration and the delay between
ejaculation and test influence the results
of seminal fluid fast detection tests
1. AP and PSA were not influenced by
spermatozoa concentration
2. PSA detection results remained
constant up to 72 h and were more
reliable after 48 h than those obtained
by AP detection

Sato et al, (2006), Int J Legal Med, Japan
174 sexual assault case from 3 forensic
lab are tested for semenogelin and PSA
from samples of clothing, body surface,
tissue paper, bed sheet vaginal swab,
anal swab, and liquid saliva.
1. Sensitivity
2. Specificity
3. DNA profiling with detection limit and
condition effect
1. Semen dilution for 200.000 folds are
the lowest detection limit available for
plasma
2. Various condition may interfere with
PSA and Sg indication. This apply on
prostate cancer, Lung SCC, and other
adenoma.
3. Male DNA profile are also detected in
conjuction for postiive Sg signal
Stubbings et al, (1985), JFSCA, Canada
Comparative Study
Postcoital from lab were tested for GGT
and p30. In addition, 144 postcoital swab
from case material were test for p30
(PSA), spermatozoa, and acid
phosphatase .
1. Stability
2. Specificity
3. Sensitivity
1. GGT in semen for crime scene proof
have high absorbance value will provide
a low specificity of analysis
2. p30 and AP provide high sensitivity
and specificity in test >8 hours.
3. ELISA test for both p30 and AP has
better sensitivity than electrophoresis.
The results also indicate a more stable
product.
Ricci et al, (1982), Ann Emerg Med,
Lousiana
Cohort Selection Cross Sectional Study
70 gynecology patients and 11 alleged
sexual assault victims are tested for
routine vaginal and papanicolau smear
for sperm identification and acid
phosphatase analysis.
1. Sensitivity
2. Specificity
3. ACP diagnostic level (Sigma units) for
sexual assault case
1. The PPV for AP test is 91.7% while PPV for
Sperm is 58.4%
2. Sperm analysis is less sensitive and
correlated poorly with time of
intercourse
3. ACP value for intercourse within 24h is
>50 (>138 sigma units/cc), while values
>20 but <50 are correlated for
intercourse wihtin 48h

Peonim et al, (2007), J Med Assoc Thai,
Thailand
Comparative study
100 vaginal specimens were examined
for prostate specific antigen by rapid
one step immunochromatographic
assay and compared with ELISA
1. Sensitivity
2. specificity
3. PPV
4. NPV
1. sensitivity is 85% for rapid one test kit
and 83% for ELISA
2. specificity is 85% for rapid one test kit
and 85% for ELISA
3. accuracy is 85% for rapid one test kit
and 85% for ELISA
4. positive predictive value is 89% for
rapid one test kit and 89% for ELISA
5. negative predictive value 79% for
rapid one test kit and 77% for ELISA
Kamenev et al, (1990), J For Sci, Belgium
Cohort Selection Cross Sectional Study
104 specimens (vagina samples (n=28),
anal (n=5), buccal (n=2), various
substances (n=69)) were examined for
p30 (PSA), ACP, and spermatozoa
examination
1. P30=absorbancy value
Spermatozoa=++++/+++/++/+/-
ACP=+++/++/+/-
2. Specificity
3. Sensitivity
1. Specificity and sensitivity for p30
detection is 95.6% and 94.8% (compare
to spermatozoa exam)
2. Specificity and sensitivity of ACP
detection is 90.0% and 84.4%
3. p30 EI test is more specific and more
sensitive than the ACP activity test

Comparison between prostate specific antigen and acid phosphatase for
detection of semen in vaginal swabs from raped women (Peonim et al, 2013)
1. Was there an independent, blind comparison with a
reference (“gold”) standard of diagnosis?
YES
• The laboratory didn’t know the situation except the
history of vaginal penetration
• Every swab was tested by 3 methods: AP activity, PSA
detection, and spermatozoa examination (GS)
2. Was the diagnostic test evaluated in an appropriate
spectrum of patients (like those in whom it would be
used in practice)?
YES
● The Patient Component (Patient in suspect of rape) are
all assessed in this case with no exclusion for severe or
mild sexual assault case.
3. Was the reference standard applied regardless of the
diagnostic test result?
YES
● Every swab was tested by 3 methods: AP activity, PSA
detection, and spermatozoa examination (GS)
1

Diagnostic Test for PSA and AP Rapid in comparison to Microscopy
AP
• Sensitivity = a/(a+c) = 65.5%
• Specificity = d/(b+d) = 96,4%
• Positive Predictive Value = a/(a+b) = 85.6%
• Negative Predictive Value = d/(c+d) = 89.4%
• Likelihood Ratio for a positive test result =
LR+= sens/(1-spec)= 18,19
• Likelihood Ratio for a negative test result= LR-
= (1-sens)/spec = 0,357
• Pre-test Probability (prevalence) =
(a+c)/(a+b+c+d) = 0,25=25%
• Pre-test-odds = prevalence/(1-prevalence) =
0,33
• Post-test odds = Pre-test odds x Likelihood
Ratio =
• Post Test Odds + = 6
• Post Test Odds - = 0,12
• Post-test Probability = Post-test
odds/(Post-test odds+1) =
• Post Test Probs + = 0,86
• Post Test Probs - = 0,1

PSA
• Sensitivity = a/(a+c) = 80,4%
• Positive Predictive Value = a/(a+b) = 77,6%
• Negative Predictive Value = d/(c+d) = 93,5%
= (1-sens)/spec = 0,21
(a+c)/(a+b+c+d) = 0,25=25%
0,33
Ratio =
• Post Test Odds + = 3,44

Combined
• Sensitivity = a/(a+c) = 84,5%
• Positive Predictive Value = a/(a+b) = 77,5%
• Negative Predictive Value = d/(c+d) = 94,7%
= (1-sens)/spec = 0,17
(a+c)/(a+b+c+d) = 0,25=25%
0,33
Ratio =

Applicability
1. Is the diagnostic test available, affordable, accurate, and precise in your setting?
a. PSA Immunochromatography are widely available in Indonesia and widely use in other
clinical procedure
b. AP test is available in indonesia, however the affordable access is quite debatable.
c. The accuracy and precision of the test kit available in Indonesia must be assessed further
with studies in Indonesia or/and the same kit that is available
2. Can you generate a clinically sensible estimate of your patient’s pre-test probability (from
practice data, from personal experience, from the report itself, or from clinical speculation)
a. Clinical sensible estimate from the pre-test probability are generated from the incidence rate
in Indonesia (4.2 case per 100.000 population) while cases in the study has a relatively small
population of test in comparison to the prevalence.
3. Will the resulting post-test probabilities affect your management and help your patient? (Could
it move you across a test-treatment threshold?; Would your patient be a willing partner in
carrying it out?)
a. Yes, because AP increase the diagnostic strength from 25% to 86%, PSA 25% to 77%,
combined 25 to 77%
b.
4. Would the consequences of the test help your patient?
a. Yes, the test would help patients with oligospermia and azoospermia causes.
Conclusion: Yes, this study is applicable to the patient.

Detection of prostate specific antigen and semenogelin in specimens from
female rape victims (Suttipasit P,)
Not mention/unclear
YES
● Every specimen was tested by sperm detection and PSA
test kit
2. Was the diagnostic test evaluated in an appropriate spectrum of patients (like those in whom it would be used in practice)?
YES
● The Patient Component (Patient in suspect of rape) are all assessed; with 6 criteria
○ Women examined at Siriraj Hospital
○ Case circumstances indicating that sexual assault may have occurred (i.e. non-consensual sexual contact
○ Women having physical wounds on the body or genitalia, or substantial evidence that these women were under duress, or under
the influence conscious-altering drugs (i.e alcohol, ketamine, etc.). Under Thai law, the definition of duress for non-consensual
sexual contact may occur under what is considered “reasonable cause/s” and includes use of weapons to coerce, use of physical
force (bodily), other forms of coercion such as blackmail (threats) and other reasonable causes as defined by the court/law
enforcement, even if there is not clear evidence of physical injuries to the genitalia or other parts of the body. Detection of
physical injury by police or doctors is just one criteria of many under this definition
○ The interval between assault and evidence collection was less than 3 weeks
○ Women had no other sexual intercourse in the intervening 3 weeks, either consensual or not, and no sexual intercourse in the 2
weeks before the alleged rape occurred
○ No evidence of condom use during the assault.
2

PSA
• Sensitivity = a/(a+c) = 32/76 = 42%
• Specificity = d/(b+d) = 92%
• Positive Predictive Value = a/(a+b) = 32/33 = 97%
• Negative Predictive Value = d/(c+d) =12/56=
21,4%
• Likelihood Ratio for a positive test result = LR+=
sens/(1-spec)= 5,25
• Likelihood Ratio for a negative test result= LR- =
(1-sens)/spec = 0,6
• Pre-test Probability (prevalence) = (a+c)/(a+b+c+d)
= 76/89 = 85%
• Pre-test-odds = prevalence/(1-prevalence) = 5,67
• Post-test odds = Pre-test odds x Likelihood Ratio =
• Post-test Probability = Post-test odds/(Post-test
odds+1) =
Positive
Sperm
Negative
sperm
Positive PSA 32 1 33
Negative
PSA
44 12 56
76 13 89

Applicability
clinical procedure
b. AP test is available in indonesia, however the affordable access is quite debatable.
c. The accuracy and precision of the test kit available in Indonesia must be assessed further
carrying it out?)
a. Yes, because it increase the diagnostic strength from 85% to 97%.
a. Yes, the test would help patients with oligospermia and azoospermia causes.

Comparable between Rapid One Step Immunochromatographic Assay and
ELISA in the Detection of Prostate Specific Antigen in Vaginal Specimens of
Raped Women (Peonim et al, 2007)
YES
● All test are run by the laboratory (blinded and
independent to the clinician and patient)
● Gold Standard are used (Sperm Microscopic Exam)
used in practice)?
YES
● The Patient Component (Patient in suspect of rape) are
all assessed in this case with no exclusion for severe or
mild sexual assault case.
● The patient that is tested are from a spectrum of cases
YES
● All specimen are being tested for the
Immunochromatographic Assay, ELISA, and the
Microscopic Sperm Examination
● All 100 specimen are being picked randomly to be used
as sample in this study
3

Diagnostic Test for PSA Rapid in comparison to Microscopy
Sensitivity = a/(a+c) = 85%
Specificity = d/(b+d) = 85%
Likelihood Ratio for a positive test result =
LR+= sens/(1-spec) = 5.67
Likelihood Ratio for a negative test
result=LR-=(1-sens)/spec = 0.18
Positive Predictive Value = a/(a+b) =
89.47%
Negative Predictive Value = d/(c+d) =
79.10%
Pre-test Probability (prevalence) = (a+c)/(a+b+c+d) = 0.60
Pre-test-odds = prevalence/(1-prevalence) = 1.5
Post-test odds = Pre-test odds x Likelihood Ratio =
● Post Test Odds + = 8.51
● Post Test Odds - = 0.27
Post-test Probability = Post-test odds/(Post-test odds+1) =
● Post Test Probs + = 0.891
● Post Test Probs - = 0.212

Diagnostic Test for PSA ELISA in comparison to Microscopy
Sensitivity = a/(a+c) = 83.33%
Specificity = d/(b+d) = 85.00%
LR+ = sens/(1-spec) = 5.55
Likelihood Ratio for a negative test result=
LR- = (1-sens)/spec = 0.196
89.29%
77.27%
Pre-test Probability (prevalence) = (a+c)/(a+b+c+d) =
0.60
Post-test odds = Pre-test odds x Likelihood Ratio =
Post-test Probability = Post-test odds/(Post-test odds +
1) =
● Post Test Probs + = 0.893
● Post Test Probs - = 0.227

Applicability
a. PSA Immunochromatography and ELISA are widely available in Indonesia and widely use in
other clinical procedure. Its affordability however must be assessed further on in
comparison to microscopic examination that is already being used in many case.
b. The accuracy and precision of the test kit available in Indonesia must be assessed further
b. Indonesia’s prevalence of sexual assault is comparable to cases in the studies country.
carrying it out?)
a. Yes, because it increase the diagnostic strength from 60% to 80% and its LR indicate a
moderate improvement of diagnosis. Its use in the procedure also does not differ making its
use more easily adopted.
a. Yes, the test would help patients with oligospermia and azoospermia causes. Thus, the PSA
test help its diagnosis without physical proof of sperm in swabs.

Detection of p30 antigen in sexual assault case material
(Kamenev et al., 1990)
UNCLEAR
● All test are tested with Spermatozoa Staining
Microscopy and p30 (AP) immunoassay
● No description of blinding in each test are presented.
Thus, there is unclear evidence of blind independent
comparison
used in practice)?
YES
● Al cases 85 exhibits from 52 forensic cases are used to
separate all case and from all samples (anal, vaginal, and
buccal in specific cases
● All of the spectrum data are present in practical cases
YES
● Both diagnostic test are run parallel to ensure the gold
standard treatment is still being used to diagnose the
patient condition
● p30 Immunoassay, EIA, and spermatozoa are used in the
first 24 hours to ensure the standard procedure still
applies.
4

Diagnostic Test for ACP in comparison to Microscopy
Sensitivity = a/(a+c) = 92.68%
Specificity = d/(b+d) = 79.41%
LR+= sens/(1-spec)= 4.50
Likelihood Ratio for a negative test result=
LR- = (1-sens)/spec = 0.09
84.44%
90.00%
Pre-test Probability (prevalence) =
(a+c)/(a+b+c+d) = 0.5467
Post-test odds = Pre-test odds x Likelihood Ratio
Post-test Probability = Post-test odds/(Post-test
odds + 1)
● Post Test Prob + = 0.844
● Post Test Prob - = 0.097

Applicability
a. While ACP is available in Indonesia, its affordability is debatable in many areas
b. Its accuracy and precision in this case provide a better implementation in readily labs around
Indonesia. Its accuracy is also dependable in the laborant skill.
b. Indonesia’s prevalence of sexual assault is comparable to cases in the studies country.
carrying it out?)
a. Yes, because it increase the diagnostic strength. Yet, its LR indicate weak improvement with
score <5.
a. Yes, the test would help patients with oligospermia and azoospermia causes as a first line
test before PSA or other DNA testing that is more sophisticated.

Evaluation of three rapid detection methods for the
forensic identification of seminal fluid in rape cases.
Journal of forensic sciences [Khalid (2004)]
VALIDITY
1. Was there an independent, blind comparison with a reference (“gold”) standard of diagnosis?
Yes.This was a prospective analytical study performed blind in vitro on anonymous sperm samples
collected at the in vitro fecundation laboratory at Pellegrin Hospital Bordeaux and having already
undergone a spermocytogramme. gold standard are used
2. Was the diagnostic test evaluated in an appropriate spectrum of patients (like those in whom it would
be used in practice)?
yes
3. Was the reference standard applied regardless of the diagnostic test result?
Yes, all samples were tested by cytology, PSA, AP and sperm detection
5

IMPORTANCE
1. Sensitivity = 67,5%
2. Specificity = 100%
3. Likelihood Ratio for a positive test
result = 0,68
4. Likelihood Ratio for a negative test
result= 0,325
5. Positive Predictive Value = 100%
6. Negative Predictive Value = 47%
7. Pre-test Probability (prevalence)
=0,775
8. Pre-test-odds = 3,34
9. Post-test odds + = 2,27
10. Post-test odds - = 1,08
11. Post-test Probability + = 0,7
12. Post-test Probability - = 0,51
Diagnostic Test for cytology in
comparison to Microscopy

IMPORTANCE
1. Sensitivity = 96%
2. Specificity = 98%
result = 0,94
result= 0,04
5. Positive Predictive Value = 99,4
6. Negative Predictive Value = 87,7
7. Pre-test Probability (prevalence) =
0,77
9. post-test odds += 3,14
10. Post-test odds - =0,13
Diagnostic Test for AP in comparison
to Microscopy

IMPORTANCE
1. Sensitivity = 99,4%
2. Specificity = 98
result = 0,97
result= 0,006
5. Positive Predictive Value = 99,4
6. Negative Predictive Value = 98
0,77 = 77%
9. Post-test odds + = 3,24
10. Post-test odds - =0,02
Diagnostic Test for PSA in
comparison to Microscopy

Applicability
clinical procedure. AP test is available in indonesia, however the affordable access is quite
debatable.
b. The accuracy and precision of the test kit available in Indonesia must be assessed further
Clinical sensible estimate from the pre-test probability
carrying it out?)
yes, because AP increase the diagnostic strength from 77% to 99,4 %, PSA 77% to 99,4%,
cytology 77% to 100%
yes
Conclusion: yes, this study is applicable for our patient

Applicability of Nanotrap Sg as a semen detection kit
before male-specific DNA profiling in sexual assaults
[Sato 2007)]
VALIDITY
Yes. Spermatozoa microscopically were examined by simple staining with fuchsin acid and methylene blue.
Yes. Forensic casework samples (174 samples) including soiled and stained clothing, victims’ body surfaces,
tissue paper samples, carpet and bed sheet samples, vaginal swabs, anal swabs, and liquid saliva samples
provided from the Scientific Crime Laboratory
Yes, all samples were tested by PSA kit.
Sg and PSA were detected by Nanotrap Sg (Rohto Pharm, Osaka, Japan) and Seratec PSA Semiquant
(Seratec Diagnostica, Gottingen, Germany) or the PSA-Check 1 (VEDALAB, Alencon, France) kits,
respectively
7
Sato et al., 2007

Diagnostic Test for AP Rapid in comparison to Microscopy
• Sensitivity = a/(a+c) = 100%
• Specificity = d/(b+d) = 67.2%
• Likelihood Ratio for a positive test
result = LR+=sens/(1-spec)= 1/32.8 =
0.03
• Likelihood Ratio for a negative test
result=LR-=(1-sens)/spec= 0/0.67 = 0
• Positive Predictive Value = a/(a+b) =
57/133 = 0.43
• Negative Predictive Value = d/(c+d) =
41/41 = 1
● Pre-test Probability (prevalence) =
(a+c)/(a+b+c+d) = 113/174 = 0.65
0.65/0.35 = 1.85
• Post-test odds = Pre-test odds x Likelihood Ratio
=
• Post Test Odds + = 5.55
• Post Test Odds - = 0
odds+1) =
• Post Test Probs + = 5.55/6.55 = 0.83
• Post Test Probs - = 0
True Diagnosis False Diagnosis
AP + 57 20 133
AP - 0 41 41
113 61 174
Sato et al., 2007

Applicability
a. ACP is available in indonesia, however the affordable access is quite debatable. Moreover
the accuracy and preciseness of this test according to the study cannot be confirmed
because the importance aspect of this study is deemed not so because of low population
usage.
a. Yes
carrying it out?)
a. Yes
a. Yes
Conclusion: Yes
Sato et al., 2007

An Evaluation of Gamma-Glutamyl Transpeptidase
(GGT) and p30 Determinations for the Identification
of Semen on Postcoital Vaginal Swabs [Stubbing, 1985]
VALIDITY
Yes. Ninety-four men contributed liquid semen samples. Of these samples, 54 contained normal numbers
of spermatozoa, 20 were oligospermic, 8 were azoospermic, and 12 were from vaseetomized individuals.
One donor submitted six successive ejaculates. Liquid semen from one donor was mixed with stains of
saliva, urine, feces, and perspiration from another donor and incubated for 48 h in a moisture chamber at
37~ Seminal stains from five donors were aged for ten weeks at 4, 22, and 37
Yes. Vaginal swabs from 144 cases of alleged sexual assault were examined.
Yes, all samples were tested by PSA and p30 (AP) kit.
VALIDITY: YES
8
Stubbing et al., 1985

Diagnostic Test for PSA Rapid in comparison to Microscopy
result = LR+=sens/(1-spec)= 8,68
result=LR-=(1-sens)/spec= 0.4
• Positive Predictive Value = a/(a+b)
= 0.97
• Negative Predictive Value = d/(c+d)
= 0.59
● Pre-test Probability (prevalence) = (a+c)/(a+b+c+d) =
0.67
● Pre-test-odds = prevalence/(1-prevalence) = 0.67/0.33 =
2.03
● Post-test odds = Pre-test odds x Likelihood Ratio =
○ Post Test Odds + = 2.03*8.68 = 17.62
○ Post Test Odds - = 2.03*0.4 =0.81
● Post-test Probability = Post-test odds/(Post-test odds+1)
=
○ Post Test Probs + = 17.62/18.62 = 0.95
○ Post Test Probs - = 0.81/1.81 = 0.45
True PSA 60 2 62
False PSA 36 46 82
96 48 144

Diagnostic Test for AP Rapid in comparison to Microscopy
result = LR+=sens/(1-spec)=
0.698/0.021 = 33.23
result=LR-=(1-sens)/spec= 0.302/0.979
= 0.308
• Positive Predictive Value = a/(a+b) =
0.85
• Negative Predictive Value = d/(c+d) = 1
● Pre-test Probability (prevalence) =
(a+c)/(a+b+c+d) = 114/144 = 0.79
0.79/0.21 = 3.77
• Post-test odds = Pre-test odds x Likelihood Ratio
=
• Post Test Odds + = 3.77*33.23 = 125.27
• Post Test Odds - = 3.77*0.308 = 1.16
odds+1) =
• Post Test Probs + = 125.27/126.27 = 0.99
• Post Test Probs - = 1.16/2.16 = 0.54
True AP 67 1 68
False AP 29 47 76
96 48 144

Applicability
usage.
a. Clinical sensible estimate from the pre-test probability
carrying it out?)
a. Yes
a. Yes
APPLICABILITY: YES

Prostatic Acid Phosphatase and Sperm in the
Post-Coital Vagina [Ricci L.R. (1982)]
VALIDITY
Unclear, The study aims to compare the sensitivity of detecting recent coitus in acid phosphatase and sperm
(through pap smear) detection. Because the gold standard of detecting coitus is through microscopic sperm
detection, the answer of this question is yes there is a gold standard comparison. As for the blinding element of
the comparison, the paper did not specify whether or not blinding method has been applied.
Yes, the spectrum of patients in this study range from gynaecology patient and alleged sexual assault patient.
Yes, Both the AP detection and sperm detection using pap smear is carried out in all patients
Conclusion: yes this study is still valid
9

IMPORTANCE
1. Sensitivity = 7/7 = 100%
2. Specificity = 4/5 = 80%
result = 1/(1-⅘) = 1/(⅕) = 5
result= (1-1)/(⅘) = 0
5. Positive Predictive Value = 7/11 =
63,64%
6. Negative Predictive Value = 0/1 =
0%
7/12 = 58,3%
8. Pre-test-odds = (7/12)/(5/12) = 1,4
9. Post-test odds = 1,4 x 5 = 7
10. Post-test Probability = ⅞ = 0,875
Microscopic
Present Absent Total
ACP Test Positive 7 4 11
Negative 0 1 1
Total 7 5 12
“12 cases ~ 24 hours, 11 were acid phosphatase-positive
(91.7%) while seven were sperm-positive (58.4%)]”
conclusion: this study has no importance because of low
population

Applicability
usage.
a. no because there isn't much data that's provided in the case.
carrying it out?)
a. there isn't much data that's provided in the case.
a. Based on the lack of importance aspect of this study, no it will not help our patient.
Conclusion: No, this study is not applicable for our patient

Critical Appraisal Summary
No Paper Appraised Validity Importance Applicability Notes
1. Peonim et al, 2013 +
2. Suttipasit et al, 2018 Blinding Unclear
3. Khaldi et al, 2004 +
4. Peonim et al, 2007 +
5.. Kamenev et al, 1990 Blinding Unclear
6.. Sato et al, 2007 +
7.. Stubbings et al, 1985 +
9.. Ricci et al, 1982 Blinding Unclear Low study population may cause
high level of error and data validity

Discussion Points
1. Effect Measures
● Its specificity in detecting sexual assault
case is sufficient
● Its sensitivity are varied with its
preparation and time used after the
alleged sexual assault
● The effect of PSA and AP testing is also
dependable on the site from it is
detected (Vaginal, Buccal, Skin, Clothes,
or Other Places)
2. Quality of Studies
● All studies are excellent in quality
● Study by Rucci et al, 1982 must not be
used because of its low population used.
● The standard use of test is already set
using the established procedure
3. Advantages and Disadvantages of
PSA and AP Test
● Advantage: Applicable in many
use case and easily used.
● Disadvantage: Lack of empirical
gold standard detection
4. Applicability in Indonesia
● It is applicable since the two test
is already widely available in
Indonesia
● Its pricing must be considered in
comparison to sperm detection

strength and limitations
1. Strength
- This is the first study on PSAAP testing a confirmatory test for
forensic sexual assault case in comparasion to direct sperm
microscopy in Indonesia.
- PSA AP are useful, quick and simple test for forensic sexual assault
case. So, PSA AP can be used clinically
2. Limitations
- The accuracy and precision of the test kit available in Indonesia must be
assessed further with studies in Indonesia or/and the same kit that is
available.
- This paper had excluded papers not english. but it would be better if we
included the as well.

Conclusion
In case of oligospermia or aspermia, the vaginal swab screening of PSA
and AP testing is applicable for alleged victims of sexual abuse. Other
use with PSA and AP testing in collaboration with sperm analysis can
help provide proof on sexual abuse case.

1. Perempuan dalam himpitan pandemi: lonjakan kekerasan seksual, kekerasan siber, perkawinan
anak, dan keterbatasan penanganan di tengah Covid-19. Jakarta: Komisi Nasional Anti Kekerasan
Terhadap Perempuan; 2021 Mar 5.
2. Peonim V, Worasuwannarak W, Sujirachato K, Teerakamchai S, Srisont S, Udnoon J, Chudoung U.
Comparison between prostate speciﬁc antigen and acid phosphatase for detection of semen in
vaginal swabs from raped women. J Forensic Leg Med. 2013 Aug;20(6):578-81.
3. Talthip J, Chirachariyavej T, Peonim AV, Atamasirikul K, Teerakamchai S. An autopsy report case
of rape victim by the application of PSA test kit as a new innovation for sexual assault
investigation in Thailand. J Med Assoc Thai. 2007 Feb;90(2):348-51.
Referensi

8A_Diagnosis_Pleno 3.pptx.pdf

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