My laboratory is on the cusp of revamping our Serology SOP and the way that we word some of our serology testing on our final reports. I know that the "word of the day" when it comes to ISO, which is where most of us are headed, is TRANSPARENCY. Nothing would make me happier and more comfortable as a forensic scientist to be able to go to court, clearly state what tests were used, and openly show/explain their limitations. Anyone that has read about the North Carolina debaucle understands that a scientist's report, despite their best intentions AND following proper protocol, can be grossly misinterpreted without them personally being present to explain it and in turn, ruin their career in forensics.
Anyhow, several of my coworkers are facing some resistance by administration when it comes to how we report out semen testing and what "weight" we give to these tests in regard to probative value. Let me also say that we were getting false (+)'s with ABAcard psa on known semen-free samples. Their was some discussion about temperature, pH, and viscosity issues that could cause these results. Due to these issues, we switched to Seratec's product. I will also state that our DNA section does tell the end of the story many times by stating whether foreign DNA is present in our swabbings and cuttings which is a small comfort to us serologists, but that sometimes, the mere reporting of semen being present is all it takes for a jury to convict, even if DNA is not obtained. I am trying to poll other forensic laboratories to see how you guys report out the following testing so that I can attend our next brainstorming meeting with some possible suggestions:
1) Spermatozoa identified
2) No Spermatozoa identified, (+) p30 result
3) No Spermatozoa identified, (-) p30 result
4) No Spermatozoa identified, p30 result(test line intensity is lighter than internal standard of 4 ng/mL)
For 1), we currently write "Semen was identified on.....".
For 2), we currently write "Semen was identified on.....".
For 3), we currently write "No semen was found on....".
For 4), we currently write "Tests for the presence of semen were inconclusive.".
Sadly, our current protocol dictates that if our test line is (+) or less intense than the internal standard, we must repeat the test with another p30 card of the same lot # (I don't see this as sound scientific practice). If the second test is also (+), we follow 1) wording as above. If the second test is (-), we are told to write "No semen was found on..." (I don't agree with this.) I know that Seratec is very sensitive. The manufacturer clearly shows examples of fainter lines being still interpreted as (+) for p30. I also know that the test line, results being based on a bell curve of concentration, may be fainter because there's low quantities of p30 OR very high quantities, approaching the high-dose hook effect level which would give you a false (-).
Do any other laboratories interpret these faint lines as anything other than (+)? Does your lab call this (+) for p30, a component of semen OR (+) for semen?
Do your reports give disclaimers about p30 being found in low levels of other body fluids?
Lastly, does your laboratory consider p30 testing to be sensitive/specific enough to be called a confirmatory test for semen? Ours has for years and doesn't want to even consider backing off on report wording to view it as presumptive, which many of us feel is imperative. There was some talk of describing it as "indicitive," but that is what the poor soul in North Carolina used and we all know how that turned out for him! We're all of the "worst-case scenario" mindset and fear one day, major consequences could befall our laboratory or us analysts though we are following SOP as set forth and attempting to remain subordinate to our superiors.
I know I've rambled for a lengthy spell here, but we've got a burden on our shoulders that needs resolution. Misinterpretation of data is not an acceptable answer for me. I don't see anywhere on Seratec's website where they consider any type of line in the Test area to be anything but (+). That is the bottom line. My signature on a laboratory report means something to me and I don't want it to lose its value.
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