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A quality assurance method is developed for measuring, verifying and analyzing intensity modulated radiation fields. It is applicable for rotational and fixed-beam intensity modulated radiation therapy(IMRT)treatments. A gantry-mount device was constructed to measure the transmission dose of an IMRT field using radiographicfilms. A double-exposure technique with optimal kernel estimate method was developed to minimize the errors from measurements. A χ 2 confidence level test method was developed to detect the discrepancies between measured and prescribed IMRT fluence distributions. Our method was tested for rotational and fixed-beam IMRTtreatment verifications. The method was found insensitive to the hardware-related parameters for rotational and fixed-beam IMRTdeliveries. The χ 2 confidence level test was found to be more sensitive than linear correlation method in detecting relative small errors for cases with a few segments or narrow regions of interest. In conclusion, we demonstrated a quantitative method for verifying and analyzing IMRTtreatmentdeliveries.

ObjectivesTo assess the impact of the introduction of a new quality control/quality assurance (QA/QC) protocol on the processing and reporting of respiratory specimens.MethodsAfter implementation of guidelines for processing respiratory specimens, an investigation was carried out over a six-month period on 200 specimens, 105 sputa, and 95 deep tracheal aspirates (DTAs), assessed blindly by two independent investigators. Data regarding disagreement were arranged into two subgroups. A minor disagreement was defined as a difference in the two assessments of 25 for either WBC count or SEC count, or one assessor reporting the specimen as non-assessable, or both assessors having a minor disagreement in both the WBC count and the SEC count.ResultsAgreement was obtained on 111 samples. For 45 specimens, a major disagreement was documented, and in 44 cases, a minor disagreement was recorded, WBC being the most common cause of divergence. Data for sputa and DTAs were examined separately: of 45 major disagreements, 64.4% were observed for DTAs, while minor disagreements were recorded mostly for sputa. The role of the settings in which samples were taken in affecting quality was studied. Among the 105 sputa, 27 were from Community Health Centers (CHCs) and 78 from hospitalized patients. Agreement between the two observers was obtained in 48.1% of CHC cases versus 60.2% of hospital samples. To investigate how many of the rejected samples presented WBC >25 suggestive of infection, we looked at the 107 samples rejected during the six-month period, grouped according to the suspected diagnosis. The highest number of rejected samples falls in the category of unrelated (non-respiratory) diagnosis, and clinical suspicion is not helpful in Gram stain interpretation. The annual saving (not culturing, not testing, and not treating) derived from this simple QC procedure totals about 5000 Euro.ConclusionsStandardization in microscopic screening of respiratory samples is difficult to achieve. Criteria for rejection must be adapted to local conditions after discussion with clinicians to increase their compliance with the newly introduced guidelines and to avoid sending unnecessary specimens. The effects on patient management and cost control are significant.

The authors have shown that the primary determinants of prostate carcinoma progression are tumor volume and the percent of the tumor comprised of Gleason Grade 4/5 cells. In the current study the authors evaluated six different techniques for the morphometric measurements of prostate carcinoma volume.A computer-assisted image analysis (NIH Image, developed and maintained by the National Institutes of Health, Bethesda, MD) was used to analyze all 108 step-sectioned prostate specimens obtained between January 1 and December 31, 1997. The authors used the Stanford technique of 0.3-cm step-sections, measuring the volume of the tumor at both 0.3-cm and 0.6-cm intervals. The other 4 methods included the authors' previous method based on an earlier image program, the ellipsoidal method (pi / 6 x width x height x length), an estimation of the square area of the largest tumor, and the maximum tumor dimension (MTD).The authors first checked the accuracy of NIH Image analysis by measuring 24 circles of widely different sizes. The mean coefficient of variation was 1.7% and the correlation between the mean circle areas measured by the NIH Image software and true circle area essentially was perfect (correlation coefficient [r] = 1 and r(2) = 0.999; P0.0001). In comparison with the authors' original computer image program using 0.3-cm step-sections measured by a different observer, r(2) with the NIH Image analysis was 0.93. Using NIH Image only, the 0.6-cm step-section method missed measurable cancers in 16.7% of 108 radical prostatectomies in comparison with the 0.3-cm step-method. The mean tumor volume with the 0.6-cm section method (P0.0001) and the ellipsoidal method (P0.05) were significantly higher than with the 0.3-cm section method. r(2) from linear regressions using the 0.3-cm step section method as the standard versus the ellipsoidal method was 0.594, and was 0.89 versus the 0.6-cm step-section method, 0.652 versus the square area estimation, and 0. 527 versus the MTD method.The results of the current study support NIH Image as a powerful software program for the morphometric measurement of prostate carcinoma volume. Pathologic processing with 0.3-cm section slices was found to be more accurate for tumor volume than the 0.6-cm section slices. The ellipsoidal method, the square area of the largest tumor, and the MTD all were found to be inferior to computer-assisted image analysis measurements. In certain clinical situations in which only estimates of tumor volume are required, the square area of the largest tumor appears to be the best choice (r(2) 0.652).

This study investigates the effect of extraction methods on the color of date syrup and the potential use of microwave power for syrup processing. Sugar solutions were extracted from dates by boiling, soaking and blending. Color and sugar content of the extracted solutions were measured, and the percentage of sugar extracted form the total fruit sugar determined. Boiling was found to be the most efficient method of extraction whereby 74% of total samples sugar was extracted. In contrast, only 54.2% of fruit sugar was extracted by blending and 42% by soaking. In addition, solutions extracted by soaking and blending had a foaming problem in the subsequent concentration process. The extraction method had no effect on the product final color. The extracted solution was concentrated using two heating methods: conventional and microwave heating at a 600 W capacity and a frequency of 2450 MHz applied at three power levels: 10, 7, and 6. In the heating process, 180 minutes were needed to achieve a 77% degrees Brix using convective heating, while it took 81, 138, and 166 minutes of microwave heating at power level 10, 7, and 6, respectively to achieve the same concentration. Water activity of the syrup was measured within a sugar content range of 50 to 80% degrees Brix and the sugar concentration at which the product is shelf stable was determined at 76%.

Evaluation of image quality of paper prints in routine CT investigations.The image quality of paper prints from 104 CT scans of daily routine investigations was analysed by three observer three observers according to a five-point ranking scale for contrast, grey level, spatial resolution, and subjective confidence in correct evaluation. Each study was rated "acceptable" or "not acceptable for documentation".In 312 ratings the mean grade for contrast was 2.7, for grey levels 3.2, and for spatial resolution 3.3. Grades ranged from 1 = very good to 5 = insufficient. Subjective confidence in correct evaluation was rated as "certain" in 77.4 %, "likely" in 18.4 % and "impossible to evaluate" in 4.2 % of cases. 93.7 % of printed CT images were rated "acceptable for documentation".Image quality of paper prints does not reach the quality of laser films concerning its contrast, grey levels, and spatial resolution. Nevertheless, paper prints are acceptable for documentation of findings in most CT investigations. A high confidence in correct evaluation was found. Limitations are found in documentation of small coin lesions of the lung and ischemic lesions of the neurocranium.

Crowdsourced psychological and other biobehavioral research using platforms like Amazon’s Mechanical Turk (MTurk) is increasingly common – but has proliferated more rapidly than studies to establish data quality best practices. Thus, this study investigated whether outcome scores for three common screening tools would be significantly different among MTurk workers who were subject to different sets of quality control checks. We conducted a single-stage, randomized controlled trial with equal allocation to each of four study arms: Arm 1 (Control Arm), Arm 2 (Bot/VPN Check), Arm 3 (Truthfulness/Attention Check), and Arm 4 (Stringent Arm – All Checks). Data collection was completed in Qualtrics, to which participants were referred from MTurk. Subjects (n = 1100) were recruited on November 20–21, 2020. Eligible workers were required to claim U.S. residency, have a successful task completion rate > 95%, have completed a minimum of 100 tasks, and have completed a maximum of 10,000 tasks. Participants completed the US-Alcohol Use Disorders Identification Test (USAUDIT), the Patient Health Questionnaire (PHQ-9), and a screener for Generalized Anxiety Disorder (GAD-7). We found that differing quality control approaches significantly, meaningfully, and directionally affected outcome scores on each of the screening tools. Most notably, workers in Arm 1 (Control) reported higher scores than those in Arms 3 and 4 for all tools, and a higher score than workers in Arm 2 for the PHQ-9. These data suggest that the use, or lack thereof, of quality control questions in crowdsourced research may substantively affect findings, as might the types of quality control items. Supplementary Information The online version contains supplementary material available at 10.3758/s13428-021-01665-8.