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QUANTITATIVE ACID PHOSPHATASE TEST - A STATISTICAL ANALYSIS OF ENDOGENOUS AND POSTCOITAL ACID PHOSPHATASE LEVELS IN THE VAGINA

NCJ Number
57024
Author(s)
G F SENSABAUGH
Date Published
January 1979
Length
20 pages
Annotation
TO PROVIDE GUIDELINES FOR THE INTERPRETATION OF ACID PHOSPHATASE (ACP) TESTS IN CASES OF SEXUAL ASSAULT, DATA FROM FOUR PUBLISHED AND ONE UNPUBLISHED STUDY ARE ANALYZED TO DEFINE ENDOGENOUS AND POSTCOITAL ACP LEVELS.
Abstract
THE STUDIES USE DIFFERENT METHODS AND DIFFERENT MEASUREMENTS, AND THEREFORE, ARE NOT DIRECTLY COMPARABLE. THE DATA WERE STANDARDIZED TO FACTOR OUT UNIT AND SCALE DIFFERENCES, LEAVING A LARGE BODY OF DATA ON MEASUREMENTS OF ACP LEVEL IN THE VAGINA. THE STATISTICAL TECHNIQUES USED ARE DESCRIBED IN DETAIL. THE RESULT WAS 130 DATA POINTS FROM STUDIES OF ENDOGENOUS ACP LEVELS IN THE VAGINA AND 178 DATA POINTS FOR POSTCOITAL VALUES. WHEN THE FIVE SETS OF STANDARDIZED DATA FOR ENDOGENOUS ACP LEVELS ARE PLOTTED CUMULATIVELY ON LOG PROBABILITY COORDINATES, ALMOST ALL THE DATA POINTS FALL WITHIN A NARROW BAND. VALUES LYING OUTSIDE THE BAND REPRESENT LOW ACP LEVELS. TABLES ANALYZE THESE DATA AND GIVE STANDARDIZED SIGNIFICANT THRESHOLDS FOR VAGINAL ACP DISTRIBUTION. THE POSTCOITAL DATA INDICATES THAT THE LEVEL OF ACP CAN BE DESCRIBED BY A LOGNORMAL DISTRIBUTION FUNCTION. THE DECLINE IN RECOVERABLE ACP ACTIVITY IS ILLUSTRATED BOTH GRAPHICALLY AND IN DATA TABLES WHILE WHOLE SEMEN AND VAGINAL ACP LEVELS ARE PROVIDED FOR REFERENCE. DURING THE FIRST 3 HOURS AFTER COITUS, THE ACP LEVEL RAPIDLY DROPS FROM VALUES IN THE WHOLE SEMEN RANGE TO VALUES INDICATING AS MUCH AS 99 PERCENT LOSS. THE INITIAL LOSS THEN BEGINS TO LEVEL OFF. AT 10 HOURS, THE MEAN LEVEL IS ABOUT 5 PERCENT OF EJACULATE WITH THE RATE OF DECAY BECOMING MORE GRADUAL (WITH A HALF LIFE OF ABOUT 70 HOURS). THESE VALUES PROVIDE INFORMATION POTENTIALLY USEFUL FOR ANALYSIS OF INDIVIDUAL CASES. THE PAPER CONTAINS EXTENSIVE TECHNICAL DISCUSSION AND A BIBLIOGRAPHY. (GLR)

Date Published: January 1, 1979