Assessing agreement among crime scene measurement methods.

A critical concern with crime scene documentation is the accuracy with which a crime scene can be reconstructed. Here, we discuss the accuracy of eight documentation methods as a function of measurement distance between reference ground targets in an outdoor scene. The relative accuracy of each documentation method was assessed with respect to a widely accepted and well-established standard method for land surveying, Total Station, from which measurements served as "ground truth" or reference data. For the majority of methods, the actual relative difference between measurements when compared to Total Station was small (less than a quarter of an inch). Measurements from FARO LiDAR agreed the most with to those of Total Station, while drone without the use of ground control points (GCPs) agreed the least. GCPs or a reference scale were also found to be important in mitigating increasing imprecision with increasing distance when measuring between two targets ~9-85 ft apart via drone and orthomosaic methods. Additionally, there were no statistical differences in the use of 2D (horizontal) or 3D (slope) measurement configurations for the Total Station. Overall, linear regression of difference plots did not reveal meaningful correlation between increasing distance measured and the error of a method when compared to Total Station. As more measurement methods become available, and the need for training and validating new tools become a necessity, these results point to the importance of establishing a ground truth or known distance range on which crime scene measurement methods can be validated.

The influence of offering free transdermal nicotine patches on quit rates in a local health department's smoking cessation program.

Nicotine replacement therapy (NRT) has added to the menu of options available to assist cigarette smokers in quit attempts, but cost remains a barrier to access. A quasi-experimental study was carried out to compare quit rates and continuous abstinence from smoking before (n=601) and after (n=311) free nicotine patches were offered to smokers who participated in the Washington County (Maryland) Health Department's "Stop Smoking for Life" group behavioral cessation program. After free NRT was offered, the quit rates upon completion of the program increased from 38% to 65% [difference 27%; 95% confidence limits (CL) 21%, 34%]. The difference in continuos abstinence from smoking between the two groups was no longer statistically significant after 6 months of follow-up, reflecting the more rapid rate of reversion to smoking that occurred during the 18-month follow-up period among the free NRT group who had quit [adjusted rate ratio (RR) 1.35; 95% CL 1.03, 1.78]. Enrollment during the first 18 months after free NRT was 37% greater than the program's first 18 months (P=.08). In conclusion, adding free nicotine patches to a smoking cessation program was associated with increased program enrollment and significantly increased short-term-but not long-term-quit rates. The rapid reversion to smoking in the group who received free nicotine patches could potentially be obviated if participants extend their use of nicotine patches after the free 6-week supply is exhausted.