A persistent conjecture regarding the potential problems in the clinical use of hair assays has been that drug concentration in hair may have a racial bias. In sociocultural terms, "bias" has a negative connotation and inherently implies a value judgment. In this controversy, however, the racial bias criticism seems to be directed at what one might call a "technical bias." In statistical use, the concept "bias" indicates a systematic departure from the random occurrence of an empirical property in any particular sample. Sociological bias becomes an issue when some consequence is attached to the empirical differentiation. Thus the "bias issue" in hair testing is a cultural one, because illegal drug use is generally considered "negative" in contemporary society and in the law. In some circumstances, the data's statistical treatment does not lend support to either a racial or a hair color bias.

This study examines the role of several disinhibitors and the distribution of the presence and absence of these disinhibitors in sexual assaults. Four prominent disinhibitors are selected: alcohol use, drug use, anger, and pornography. Three types of sexual assaults are considered: assaults including sexual intrusion/penetration, assaults including physical violence, and assaults ending in the death of the victim. A conjunctive analysis is used to examine the distribution of these variables both singularly and in all possible combinations.

This article presents results from 1872 hair samples, which were analyzed for fatty acid ethyl esters (FAEEs) and ethyl glucuronide (EtG). The results were evaluated in the context of self-reported drinking behavior, the use of hair cosmetics, the gender of the sample donors and hair sample length. For comparison, CDT and GGT in serum were available in 477 and 454 cases, respectively. A number of alcohol abstainers or low moderate drinkers and excessive drinkers were selected for assessment of cut-offs for FAEEs in the proximal 6 cm hair segments and for EtG in the proximal 3 cm hair segments. Cut-off values were assessed by ROC analysis. It was found that the cut-offs of 1.0 ng/mg FAEE and 30 pg/mg EtG presently used for excessive drinking lead to a low portion of false positives (4% and 3% respectively) but to a higher portion of false negatives (23% and 25% respectively). Comparison of the mean and medium concentrations in samples without any reported hair cosmetics (N = 1079) and in samples with reported use of hair spray (N = 79) showed an increase by the factor of about two for FAEE but no significant difference for EtG. Mean values of EtG were decreased by 80% in bleached samples (N = 164) and by 63% in dyed samples (N = 96). There was no significant effect of bleaching and dyeing on FAEE. Hair gel and hair wax, oil or grease showed no significant effect on both FAEE and EtG. With respect to gender and investigated hair length ambiguous results were obtained because of major differences in the compared subpopulations of male with higher alcohol consumption and mainly shorter hair, and less drinking female with longer hair. For excessive drinkers FAEEs in the 0–6 cm hair segment and EtG in the 0–3 cm segment decreased with increasing time of reported abstinence before sample collection. These drinkers attain the level of teetotalers only after more than 10 months of abstinence. In comparison to scalp hair, FAEEs recovered from armpit hair and leg hair were lower and from chest hair were higher. EtG in armpit hair was lower and in leg hair higher than in scalp hair. It is concluded that the combined use of FAEE and EtG essentially increases the accuracy of interpretation since both markers complement each other by a different sensitivity to sources of error.

Circumstances under which a sexual assault takes place and how these circumstances affect offenders’ reactions to victim resistance are not well understood. Previous studies have not thoroughly examined the interactions that take place between situational factors and resistance. Using a combination of logistic regression and Chi-square Automatic Interaction Detection (CHAID) analyses, we examine victim, situational, and crime characteristics of 426 sexual assaults involving victim resistance to determine which of these factors increase the likelihood of offender violence. Findings suggest that violence is affected by both the attack strategy employed by the offender and the type of resistance by the victim, along with several other qualifying factors.

This study examines what factors may distinguish injury from death in sexual crimes. We suggest that victim characteristics may work in conjunction with the crime context to enhance or reduce a fatal outcome once a sexual assault is underway. Based on a sample of 201 sex offenders who either physically injured or killed their victim, we calculate risk estimations of lethal and injurious outcomes for various conjunctions of victim characteristics and contextual aspects of the crime event. One of the most interesting findings is the apparent protective effects of a victim's criminogenic environment, which consistently appears to decrease the probability of a fatal outcome.

The study aimed to examine sex offender characteristics associated with a decision to confess. Based on the analysis of 624 sex offenders, our findings showed that, depending on the type of sex offender, different characteristics are associated with their likelihood of confessing during the police interrogation. Moreover, distinguishing between those who fully confess and those who only confess partially yielded mixed findings. Finally, our results showed that confession was not static and that offender characteristics were associated with a decision to confess once admitted to the prison. The findings are discussed in light of the implications for interrogation strategies.

In a variety of decision settings when categorical information is the data in hand, the correspondence between an indicator test and a true condition (i.e., an accepted "gold standard") is often assessed by the use of comparison or "truth" tables. The results from such a table can be considered an informational yield and allow a practitioner to assess the utility of the indicator test in various ways, such as specificity and sensitivity, false positive and negative rates, and the positive and negative predictive values. There are many reasons for the use of an indicator test. This article proposes a novel application of an informational measure in determining the utility of hair and urine specimens for clinical decision making. It does this for two commonly abused substances, cocaine and cannabinoids. It suggests that in clinical applications the ability to assess informational yield is an important factor in developing clinical strategies for treatment of addictive disorders.

Purpose - The purpose of this study is to identify factors in sex offenders that act to facilitate or inhibit confession to police. Moreover, it aims to assess possible interactions and differences among factors related to confession specifically for child molesters and those who attack adult victims (rapists).Design/methodology/approach - The authors use a combination of CHAID and conjunctive analysis to analyze interactions and factors significantly associated with confession to police in a sample of 624 sex offenders.Findings - The study identifies several factors, as well as interactions among those factors, related to confession to the police. Moreover, rapists and child molesters present different factors related to confession, the former being more related to the criminal event as to the latter being more related to the offender characteristics.Practical implications - The findings point to the conclusion that investigators need to pay careful attention to the type of victim when preparing the interrogation. Moreover, these crime event characteristics are readily observable factors that can improve the estimation of the likelihood of obtaining a confession. Finally, the several interactions identified confirm the complexity of the decision making leading to confession to police as well as the need to look at the factors in combination as opposed to individually.Originality/value - This paper is the first attempt to apply a combination of innovative multivariate statistics (CHAID) and a qualitative technique (conjunctive analysis) to investigate factors leading to confession for two specific types of sex offenders.

The purpose of this article is to compare the differential rate of detection of illicit drugs when using two distinct sample types, hair and urine specimens. The specimens were collected from persons who applied for employment as a truck driver, or were collected from randomly selected currently employed truck drivers. The data is examined for job applicants and employees to determine if any differences in outcomes are associated with employment status or specimen type. The data is also assessed for specific patterns associated with particular drugs and their assay outcomes. Overall, it was determined that drug positive cases are relatively rare. Job applicants are more likely to test positive for an illicit drug than a currently employed driver. Applicants are more frequently positive for a drug by a factor of 3 for both urinalysis and hair analysis when compared to currently employed drivers. Approximately 2% of applicants were urine positive and 9% hair positive for an illegal drug. Considering employed truck drivers 0.6% were drug positive by urinalysis and 3% when using hair analysis. It is concluded that hair assays detect more drug use than urinalysis. It is also concluded that when urine and hair assay outcomes are non-concordant the typical case is a positive hair analysis with a negative urinalysis.

For diagnosis of chronic alcohol abuse, fatty acid ethyl esters (FAEE) were determined in hair samples from 644 individuals, mainly parents from child protection cases. The analysis for ethyl myristate, ethyl palmitate, ethyl oleate and ethyl stearate was performed according to a validated procedure consisting of external degreasing by two times washing with n-heptane, extraction with a mixture of dimethylsulfoxide and n-heptane, separation and evaporation of the n-heptane layer, headspace solid phase microextraction of the residue after addition of phosphate buffer pH 7.6 and gas chromatography-mass spectrometry using deuterated internal standards. For interpretation, the sum of the concentrations of the four esters C(FAEE) was used with the cut-off's 0.5 ng/mg for the proximal scalp hair segment 0-3 cm or less and 1.0 ng/mg for scalp hair samples with a length between 3 and 6 cm and for body hair. C(FAEE) ranged from 0.11 to 31 ng/mg (mean 1.77 ng/mg, median 0.82 ng/mg). The mean concentration ratio between the 4 esters was 8:45:38:9. 298 cases had C(FAEE) above the cut-off's. Self-reported drinking data were obtained in 553 of the cases in the categories abstinent (156 cases), moderate drinking (252 cases) and excessive drinking (145 cases). Median and box-plot data clearly demonstrate differentiation of these ingestor sub-populations by C(FAEE). However, in the abstinent and moderate groups the consumption was frequently underreported (37 and 110 cases positive) whereas in the group self-reported excessive drinking 32 cases were negative. Comparison of C(FAEE) with carbohydrate-deficient transferrin (CDT) in 139 cases and gamma-glutamyltransferase (GGT) in 136 cases showed a good agreement in CDT- and GGT positive cases (27/28 and 32/41) but a large portion of the negative CDT- and GGT-results with positive hair test (44/100 and 48/95) which is explained mainly by the much shorter time window of CDT and GGT. No significant correlation was found between persons weight and C(FAEE) showing that the test is not biased against physical fitness or obesity. Furthermore, there was no statistically significant difference between scalp hair (541 samples) and hair from other body sites (84 samples). In conclusion, FAEE in hair appeared to be suitable markers for the detection of excessive drinking. However, as there is no proportionality between drinking amount and C(FAEE), the additional use of other markers can increase the reliability of the interpretation.

This article examines the conjecture that hair analysis, performed to detect cocaine use or exposure, is biased against African Americans. It does so by comparing the outcomes of 33,928 hair and 105,792 urine samples collected from both African American and white subjects. In making this comparison the analysis seeks to determine if there is a departure in rates of positive and negative outcomes when comparing the results of hair analysis for cocaine to the results from urinalysis for cocaine by racial group. It treats urine as an unbiased test. It compares both the relative ratios of positive outcomes when comparing the two groups and it calculates the relative risk of outcomes for each group for having positive or negative outcomes. The findings show that the ratios of each racial group are effectively same for hair and urine assays, and they also show that the relative risk and risk estimates for positive and negative outcomes are the same for both racial groups. Considering all samples, the cocaine positive risk estimate for the hair samples comparing the two racial groups is 3.28 and for urinalysis the risk estimate is 3.10 (Breslow-Day χ(2) .250, 1 df, p = 0.617) a non-significant difference in risk. For pre-employment samples, the cocaine positive risk estimate for the hair samples comparing the two racial groups is 3.10 and for urinalysis the risk estimate is 2.90 (Breslow-Day χ(2) .281, df = 1, p = 0.595), also a non-significant difference in risk.

is still daunting. In principle, one would need to consider all these features and adjustments jointly, and there are yet many unknowns. For instance, Planty proposes plausible adjustments for undercounting of repeat victimizations in the calculation of NCVS crime rates. He notes, though, that because the UCR may well undercount series victimization too, one is not quite sure what to make of changes in the apparent divergence between the two data sets’ trends when the NCVS is adjusted for series victimization. Also, along with design issues, the psychology of recall by survey respondents and organizational factors that influence the police classification and reporting of crimes need to be considered. (These areas are noted but are not the main concern of these chapters.) Work is therefore far from done, and of course some of the analyses here seem more satisfying than others, but these articles definitely will be important building blocks for future literature on this topic. The editors’ main goal is to understand the two systems’ complementarity and how each should be used, not to judge one as correct (or more correct) under some external criterion. A focus on complementarity is appealing because it recognizes the inherent complexity of the phenomenon of crime and ambiguity in its definition, and directs attention to the substantive utility of each system rather than the pursuit of convergence. McDowall and Loftin argue that because actual convergence of crime trends under the two systems is probably possible in only a rather weak or technical sense, the most reasonable conclusion is simply to use each data set for the purposes for which it is best suited. Certainly this conclusion seems sensible to researchers, as criminologists will naturally seek out the particular data that can most convincingly address their research questions. However it is important to recognize that even if researchers accept this view, policymakers and the public will likely continue to notice and be concerned with differences in the two systems’ measurements of the overall level of crime. And, of course, much of the book itself examines the impact of specific adjustments on apparent convergence or divergence. Complementarity also cannot be a reason to ignore problems of design or measurement in either system. Still, there is a solid case for complementarity as the appropriate viewpoint when considering the two systems. The conclusion offers some suggestions for reporting the two systems’ findings in a way that both respects complementarity and is useful for the public. The editors also advocate a more ‘‘systemic’’ approach to collecting crime data than is afforded by the current NCVS and UCR. While the practical meaning of this recommendation needs to be fleshed out a good deal more, it is indeed critical for criminologists to consider the future of large-scale crime data collection in terms of both research needs and the reporting of crime statistics to the public. This book is a good stimulus to thinking about that future.

This paper examines violent sexual assaults and the factors associated with those assaults with lethal outcomes. It utilizes a criminal events perspective in conceptualizing the nature of these assaults and divides the event into three domains: victim characteristics, situational characteristics, and crime characteristics. Using a method developed by Miethe, Hart, and Regoeczi, conjunctive analysis of case configurations, we find that certain characteristics of the crime itself and certain characteristics of the victim appear strongly associated with fatal outcomes in sexual assaults, while situational characteristics appear relatively weakly associated with lethality.

Purpose. This study applies a Bayes analysis to the probability of a particular STATIC-99 score and its associated re-offence probability with recidivating for a sexual offence. We examine this probability over three time frames: within 5 years; within 10 years; and within 15 years.Methods. This study was conducted using the same data from Hanson and Thornton (1999). This dataset is constituted from four different samples: Institut Philippe Pinel (Canada) sample; Millbrook Recidivism Study (Canada) sample; Oak Ridge Division of the Penetanguishene Mental Health Center (Canada) sample; and Her Majesty's Prison Service (UK) sample. The final sample for which sufficient information was available to score the STATIC-99 includes 1,086 sexual offenders. Bayes statistic has been used to analyse the data.Results. Results are consistent with the STATIC-99 as a useful assessment tool. The Bayes-generated probabilities as well as odds ratios show a consistent increase in increased likelihood of re-offence as the score value increases.Conclusions. The Bayesian analysis of the STATIC-99 shows that this method is very interesting in the context of risk assessment tools. This approach to risk assessment instruments may be more appropriate in the communication of analytic results as it can offer clinicians a combination of probabilities and likelihood ratios resulting a readily accessible profile of risk.

This paper examines the hypothesis that cocaine and BE assays of hair demonstrate a putative bias effect for darker color hair samples. Although such an effect has been reported in the literature, no one has examined this claim outside the bounds of simple significance of mean difference. In this paper a large number of black and brown hair samples are compared for cocaine and BE concentration values, and this comparison is evaluated for both significance and effect size. Two innovative measures are used to assess this relationship - a calculation of effect size using Cohen's d, and the use of an ROC curve to evaluate the potential for a dark color bias. The paper reports mixed results for significance, but consistent results for effect size. There does not appear to be any significant effect for cocaine. While BE demonstrates a significant mean difference, both the effect size and the ROC analysis show the effect to be trivial.