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1.
With the ever increasing production of average soft tissue depth studies, data are becoming increasingly complex, less standardized, and more unwieldy. So far, no overarching review has been attempted to determine: the validity of continued data collection; the usefulness of the existing data subcategorizations; or if a synthesis is possible to produce a manageable soft tissue depth library. While a principal components analysis would provide the best foundation for such an assessment, this type of investigation is not currently possible because of a lack of easily accessible raw data (first, many studies are narrow; second, raw data are infrequently published and/or stored and are not always shared by some authors). This paper provides an alternate means of investigation using an hierarchical approach to review and compare the effects of single variables on published mean values for adults whilst acknowledging measurement errors and within-group variation. The results revealed: (i) no clear secular trends at frequently investigated landmarks; (ii) wide variation in soft tissue depth measures between different measurement techniques irrespective of whether living persons or cadavers were considered; (iii) no clear clustering of non-Caucasoid data far from the Caucasoid means; and (iv) minor differences between males and females. Consequently, the data were pooled across studies using weighted means and standard deviations to cancel out random and opposing study-specific errors, and to produce a single soft tissue depth table with increased sample sizes (e.g., 6786 individuals at pogonion).  相似文献   

2.
On the basis of simultaneously sampled postmortem blood specimens from the left and right femoral veins the pre-analytical variation of methadone measurements was evaluated and compared to the analytical variation. The material consisted of a series of 27 duplicate samples from routine autopsy cases comprising mainly drug addicts. A chiral LC-MS/MS method was used for measurement of the R- and S-enantiomers of methadone and its main metabolite 2-ethyl-1,5-dimethyl-3,3-diphenylpyrrolinium (EDDP). The analytical CV% was determined to be in the range 3-4% for methadone enantiomers and 4-6% for EDDP enantiomers. The total measurement uncertainty (CV(T)) was estimated from the pre-analytical variation (CV(PA)), analytical variation proper (CV(A)), and variation related to calibration (traceability) (CV(Cal)) according to the relationship CV(T) = [CV(2)(PA) + CV(2)(A) + CV(2)(cal)](0.5). Uncertainty related to calibration concerned a component related to the purity of drug reference compound and a contribution from the production of calibrator solutions (CV(Cal)<1%). Pre-analytical sampling variation was estimated from the duplicate measurements of blood samples after subtraction of the analytical component. The pre-analytical variation amounted to a CV% of 19-21% for R- and S-methadone and 30-38% for R- and S-EDDP, i.e. considerably larger than the other components. Due to the squared addition principle, the resulting total uncertainty (CV(T)) became largely identical to the CV(PA), i.e. 19-21% for R- and S-methadone and 31-38% for R- and S-EDDP enantiomers. Accordingly, CV(T) exceeded CV(A) by a factor 5 or more. Dominance of the pre-analytical component of variation may also be likely for other compounds measured in postmortem blood samples. Thus, the width of the 95%-uncertainty interval (+/-2CV(T)) for a postmortem measurement is largely determined by the pre-analytical component of variation. This should be kept in mind when judging on the uncertainty of postmortem measurement results.  相似文献   

3.
From the works of Broca and Krogman to modern-day Jantz and Buikstra, the orbit has been used for both quantitative and qualitative sex and race estimation. This study evaluates the practical value of these estimations. Orbital height and breadth were measured to determine the orbital index and assess differences between men and women or black people and white people in the Hamann-Todd Collection. Replicability of these measures was also examined. Finally, a geometric morphometric study was performed to assess shape differences using the entire margin. Significant differences were found in both the index and the geomorphometric study; however, further investigation revealed that the differences were of little practical use. The measurement differences were found to be smaller than intra-observer error, while the geometric morphometric analysis demonstrated that minimal percentage of variation in shape was attributable to group differences. Thus, these techniques should not be used to estimate sex or race.  相似文献   

4.
This article contends that routine activity theory has virtually ignored the motivated offender construct in terms of its measurement. We extend previous research testing routine activity theory by more accurately modeling the effects of labor market segmentation and other structural sources of offender motivation on variation in crime rates. A revised routine activity model is tested using data for the 100 largest cities in the US in 1980. The findings suggest that as secondary labor markets grow, urban crime can be expected to rise.  相似文献   

5.
6.
An understanding of the variability of the anterior human dentition is essential in bitemark analysis. A collection of 1099 3D laser scans of paired maxillary and mandibular arches were studied using geometric morphometric methods. Analyses were performed without scale (shape only) and with scale (shape and size). Specimens differing by no more than experimentally obtained measurement error were counted as matches, or as indistinguishable. A total of 487 maxillary (396 size preserved), 131 mandibular (83 size preserved), and one paired dentition (two size preserved) matches were found. Principal component analysis and partial least squares revealed interpretable patterns of variation and covariation in dental shape, principally dominated by variation in dental arch width. The sensitivity of match rate to assumed degree of measurement error was also determined showing rapid increases in match rate as measurement error increased. In conclusion, the concept of dental uniqueness with regard to bitemark analysis should be approached with caution.  相似文献   

7.
Breath alcohol measurement has variability resulting from instrumental, procedural and biological components. Reliable estimates of the standard deviation (S.D.) are necessary for calculating uncertainty in the form of confidence intervals. These estimates are concentration dependant and can be obtained from models derived from duplicate breath test data. Duplicate data from four state jurisdictions (Alabama using the Drager 7110, Minnesota using the Intoxilyzer 5000, Washington using the BAC Datamaster and Wisconsin using the Intoximeter EC/IR) were analyzed to derive predictive models for standard deviation as a function of concentration. All jurisdiction/instrument combinations yielded forensically acceptable variation while showing a general linear increase in standard deviation with concentration. This is consistent with a multiplicative error model. Jurisdictions using the same instruments but not performing duplicate analyses could also employ the straightforward models derived here to estimate standard deviations for their measurement results.  相似文献   

8.
汉魏六朝诗坛的显著特征是新变,这也是它在中国诗歌史上重要意义所在.具体表现为,诗歌作品记名的普遍化、诗歌地位下移并保持平凡身份、注重形式创造、实现从歌诗到诗歌的转变.该时期诗风更迭频繁而较多个人色彩,"教化"意识相对薄弱而审美追求异常活跃,皆是以上新变诸气象的反映.以前正统诗论视六朝诗歌为代降的过程,并以梁陈两朝为诗歌史上最低谷时期,这种见解至今仍有一定的影响.因此,认识汉魏六朝的新变特征和意义,有助于完善诗歌史的发展观念.  相似文献   

9.
The procedural justice theory of police legitimacy has received substantial empirical support, yet too little attention has been paid to the operationalization and measurement of these important theoretical constructs. In particular, it is unclear whether the items used to represent procedural justice and police legitimacy possess convergent and discriminant validity. The current study uses confirmatory factor analysis to test for the measurement properties of these constructs and expands upon prior research by also including a measure of encounter-based procedural justice in addition to a scale tapping into global beliefs. The results provide mixed support for discriminant and convergent validity between legitimacy and global procedural justice. Full structural equation models test an alternative specification of one of the popular measurement methods for legitimacy, and compare the relative impact of each type of procedural justice. The findings indicate that while specific procedural justice predicts legitimacy, global procedural justice has a stronger influence. Implications for measurement and police policy are discussed.  相似文献   

10.
目的研究耳廓观测指标的变化特征,提出利用耳廓特征识别点进行个体同一认定的研究方法,为法医学个体识别,及对视频图片中的个体进行同一认定,提供一种科学、准确、简便易行的方法。方法通过对19岁至22岁的汉族成人拍摄耳廓侧位图像,选取148人照片中的相应指标进行观测,数据收集,经SPSS统计软件处理,分析各种因素对测量结果的影响,计算出各指标识别能力及两批照片各指标之间的差值,最终得出各指标差值的参考值范围。结果 10项观测指标经统计检验分析,最终保留6项指标,重复测量结果稳定。各指标的变异系数相差不大,结果稳定可靠。结论通过制定6项观测指标差值的参考范围,确定指标是否同一,最终认定照片中耳廓是否属于同一个体的方法准确可行。  相似文献   

11.
Sex and race variation of the occipital bone have been previously investigated, but particular examination of the effect of age and ancestry on sexual dimorphism has not been addressed. This paper examines morphological variation associated with sex and ancestry in the condylar region of the occipital bone and the effect of age and ancestry on the estimation of sex. Models previously published by Holland are also tested, and methodological problems are addressed. The results indicate that age does not have an effect on sexual dimorphism, but that whites exhibit greater, although not significantly, more sexual dimorphism than blacks. Significant sex and ancestry variation is present in the condylar region of the occipital bone, but neither sex nor ancestry could be estimated accurately using measurements of this anatomical region defined by Holland.  相似文献   

12.
Small area analysis: a review and analysis of the North American literature   总被引:17,自引:0,他引:17  
Variations in health service use rates by geographic area have long interested researchers and policymakers. Typically, investigators comparing population-based health care utilization rates among geographic areas have demonstrated substantial variations in use among seemingly similar communities. One method of investigation is "small area analysis." Numerous areas in North America have been studied extensively using this technique. This research has attempted to document the amount of variation found in health care use rates among areas; determine whether or not there is a pattern to such use in high- versus low-use areas; and identify the variables that are associated with the variation and explain a portion of the variation. Beyond this, many researchers have attempted to ascertain whether such variables are associated with characteristics of the population, whether they reflect differences in access and need, or whether a substantial portion of the variation is associated with differences in the medical care system itself. This review discusses the methods used to define the areas, the dependent variables that have been studied and the patterns found within them, the independent variables that have been tested, the statistical methods and analysis procedures used, the results of each study, and the policy recommendations emanating from the research. More importantly, based on what has been learned, the paper provides researchers in small area analysis with a set of recommendations for both analyzing and reporting results. These recommendations are designed to facilitate the development of a common research methodology, increase the comparability across studies, and enhance the use of this technique in the health policy formulation process.  相似文献   

13.
Osteometric data are of great importance for analytical purposes in the field of forensic anthropology, and it is critical that interobserver concordance is high in order for the results of these analyses to be reliable. Significant interobserver variation of skeletal measurements is cause for concern since it may result in conflicting conclusions. The range of interobserver variation of selected postcranial measurements is addressed. Thirteen standard measurements familiar to most forensic anthropologists were examined, as well as nine nonstandard measurements that were unfamiliar to most participants in the study. Sixty-eight individuals participated in the study, the majority of whom considered themselves to be forensic anthropologists with various levels of experience. In general, interobserver variation of the tested standard postcranial measurements was found to be minimal, with the exception of pubis length and subtrochanteric femur measurements. The difficulties that can lead to measurement error are discussed and possible solutions are recommended.  相似文献   

14.
15.
The estimation of the post mortem period, in cases where death occurred under suspicious circumstances, is usually attempted using temperature measurements taken at a single body site. Early investigations of the validity of such an approach use the abdominal skin surface, the axilla and the rectum as measurement sites (B.H. Knight, Forensic Sci. Int., 36 (1987) 47-55). However, it has recently become more common to use the rectum alone, though the ear and the nasal passages have also been utilized. Whatever site is employed, the estimates are frequently found to be inaccurate. There are several fundamental reasons for these inaccuracies, the most prominent being the unknown variation in the ambient temperature between the time of death and the commencement of measurements, and the unknown body temperature at the time of death. This paper proposes a method of overcoming the above difficulties by taking a series of measurements concurrently at a number of body sites, a technique used by several previous workers (B.H. Knight, Forensic Sci. Int., 36 (1987) 47-55). Initial investigations have shown that an improved estimation of post mortem period is obtainable by the application of a suitable decision-making algorithm.  相似文献   

16.
Measuring trajectory angles of bullet defects at a crime scene is an important part of crime scene investigation as these angles can be used for shooting incident reconstructions. The Washington State Patrol Crime Scene Response Team (WSP CSRT) had a desire to report and use measured trajectory angles. To report quantitative measurements, a statement of uncertainty for the measurement must also be reported due to an accreditation requirement through the ANSI National Accreditation Board (ANAB), through which the WSP CSRT is accredited. This evaluation examined the measurement uncertainty of the 3D laser scanning method that the WSP CSRT utilizes for measuring the vertical and azimuth angles from trajectory rods fitted to bullet defects. Three studies were performed which examined the variation of vertical and azimuth angle measurements from trajectory rods on flat surfaces, the variation of azimuth angle measurements from a trajectory rod on a curved surface, and a traceability study with known vertical and azimuth angle measurements. Seven common substrates were selected as target materials and were shot with 9 mm Luger and 0.45 Auto caliber bullets. A vehicle with one bullet defect was utilized for the curved surface study. The WSP's current fleet of Trimble X7 3D laser scanners, the WSP Criminal Investigation Division (CID) Detectives who operate these scanners, and the Forensic Scientists responsible for trajectory rod placement and angle measurements were utilized. An overall measurement uncertainty of +/− 2.6 degrees at an approximate 95% confidence interval was determined for all trajectory angles measured from trajectory rods.  相似文献   

17.
《Science & justice》2021,61(5):649-656
A two-dimensional linear measurement approach for footprints, herein referred to as the “Reel Method,” has been shown to be valid and reliable when used on bare footprints, however, few measurement approaches have been examined on sock-clad footprints. The present investigation examines the validity and reliability of the Reel Method as a two-dimensional linear measurement approach for use on sock-clad footprints.A walking, mid-gait footprint was collected from 30 volunteer participants using the Identicator Inkless Shoe Print Model LE 25P system. The width of the ball of the foot, calcaneal width, and distance from the most posterior aspect of the heel to the most distal aspect of the first toe were each measured and compared between and within three raters. The statistical analysis demonstrated high reliability of the Reel Method among these three raters. The data were found to be normally distributed, and measurements were consistent between and within raters. 95% Intraclass Correlation coefficients, 95% Bland-Altman Limits of Agreement and 95% Standard Error of Measurement determined high statistical agreement between and within raters, demonstrating that the Reel Method is reliable and thus valid for the linear measurement of sock-clad footprints.  相似文献   

18.
The conditions for the elution of IgG in seminal stains have been investigated systematically. The amount of IgG recovered could neither or hardly be influenced by variation of the time (15 minutes to 120 hours) and temperature (4 degrees C, 20 degrees C, 37 degrees C, 56 degrees C) of elution, nor by mechanical treatment (cutting in small pieces, crushing), ultrasonic treatment or addition of a detergent. For fresh traces and such of an age of several weeks an elution time of 30 minutes at room temperature is sufficient; for very old stains an elution up to 2 hours may be recommended for safety. The investigations were restricted to the measurement of the IgG concentration in the eluates. No statement can yet be given about the biological value of the IgG for Gm typing due to this investigation alone.  相似文献   

19.
Forensically identifying a suspect's dentition from a bitemark in an open population requires the supposition that every person's dental alignment is different. There have been few studies that have tested this claim. Four hundred and ten lower anterior dentitions from a selected population and 110 lower anterior dentitions from one that was orthodontically treated were measured using geometric morphometric analysis, allowing comparison of arch shape. Dental match rates of 1.46% and 42.7% of individuals were found in the respective populations, given an established measurement error. Orthodontic treatment had a strong effect on match rate suggesting that treated or naturally well-aligned dentitions may be indistinguishable. Sexual dimorphism was found to be only slightly significant. Principal shape variation in both populations was degree of arch curvature. Results of studying these populations show that dental matches can occur, and that statements of certainty concerning individualization in such populations should be approached with caution.  相似文献   

20.
Anomie is a highly prominent theoretical construct in macro-social, particularly cross-national, criminological inquiry. Yet despite its prominence, it has proven to be quite elusive with regard to its measurement and, hence, making it nearly impossible to test theoretical hypotheses regarding its predictive efficacy. Although the concept, whether derived from Merton's classic conceptualization or from its current incarnation in the form of institutional anomie as developed by Messner and Rosenfeld, is multidimensional and complex in its theoretical structure, most researchers have attempted to operationalize it through simple, single-item, often surrogate/proxy measures. The present research note attempts to develop a measure that is more consistent with its multidimensional and complex nature. This more complex operationalization is then examined with regard to its efficacy at predicting cross-national levels of both homicide and theft. Our results suggest that that this new operationalization has considerable predictive efficacy, accounting for approximately one third of the variation in the cross-national level of both homicide and theft.  相似文献   

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