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Objective: The population-based colorectal cancer screening guidelines in Japan recommend an annual fecal immunochemical test (FIT). However, there is no consensus on the need for annual FIT screening for patients who recently performed a total colonoscopy (TCS). Therefore, we evaluated the repeated TCS results for patients with positive FIT after a recent TCS to assess the necessity of an annual FIT. Methods: We reviewed patients with positive FIT in opportunistic screening from April 2017 to March 2022. The patients were divided into two groups: those who had undergone TCS within the previous 5 years (previous TCS group) and those who had not (non-previous TCS group). We compared the detection rates of advanced neoplasia and colorectal cancer between the two groups. Results: Of 671 patients, 151 had received TCS within 5 years and 520 had not. The detection rates of advanced neoplasia in the previous TCS and non-previous TCS groups were 4.6% and 12.1%, respectively (p < 0.01), and the colorectal cancer detection rates were 0.7% and 1.5%, respectively (no significant difference). The adenoma detection rates were 33.8% in the previous TCS group and 40.0% in the non-previous TCS group (no significant difference). Conclusions: Only a few patients were diagnosed with advanced neoplasia among the patients with FIT positive after a recent TCS. For patients with adenomatous lesions on previous TCS, repeated TCS should be performed according to the surveillance program without an annual FIT. The need for an annual FIT for patients without adenomatous lesions on previous TCS should be prospectively assessed in the future.
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The FDA published a final rule for Medical Devices; Laboratory Developed Tests in the Federal Register on May 6, 2024, which aims to ensure the safety and effectiveness of laboratory developed tests (LDTs) by amending current regulations. The rule also includes a policy to phase out the FDA's general enforcement discretion approach for LDTs, aligning them with other In Vitro Diagnostic Devices. Notably, direct-to-consumer (DTC) testing is exempt from this policy shift, as the FDA believes this category of tests has already met applicable requirements. This rule was first proposed in the Federal Register on October 3, 2023. The publication of this proposed rule sparked a considerable volume of public reactions during the comment period of the rule-making process, comprising general sentiment, key concerns, and suggestions. This commentary analyzes these concerns, particularly focusing on DTC tests, and offers recommendations, including reassessing the FDA's enforcement discretion for hybrid DTC tests, advocating for clear guidance on clinical oversight, and prioritizing a risk-based enforcement approach. Additionally, enhancing public education about the risks of DTC testing is crucial for safeguarding public health.
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Over the last decades, behavioural tests in animals, especially rodents, have been a standard screening method to determine the mechanisms of action and efficacy of psychopharmacological compounds. Yet, recently the reproducibility of some of these tests has been questioned. Based on a systematic review of the sensitivity of mouse behavioural tests to anxiolytic drugs, we analysed behavioural outcomes extracted from 206 studies testing the effect of diazepam in either the open-field test or the hole-board test. Surprisingly, we found that both the rationale given for using the test, whether to detect anxiolytic or sedative effects, and the predicted effect of diazepam, anxiolytic or sedative, strongly depended on the reported test results. The most likely explanation for such strong dependency is post hoc reasoning, also called hypothesizing after the results are known (HARKing). HARKing can invalidate study outcomes and hampers evidence synthesis by inflating effect sizes. It may also lead researchers into blind alleys, and waste animals, time and resources for inconclusive research.
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Background: Orthostatic intolerance (OI) is the inability to tolerate orthostatic stress during any postural change. The etiology of OI varies, and methods to obtain a specific diagnosis and plan appropriate treatment are important. The tools available within the Chinese context to swiftly identify orthostatic intolerance syndrome (OIS) are currently limited. Methods: Patients with OI symptoms were included in this study and categorized into two groups based on the results of the supine-to-stand test. Those with abnormal test results were assigned to the OIS group, while those with normal test results were placed in the non-OIS group. We evaluated the internal consistency and predictive value of the Chinese Orthostatic Discriminant and Severity Scale (ODSS) by comparing patients' scores with their physiological measurements collected during orthostatic stress tests and the results of other available questionnaires, including the orthostatic Symptom Questionnaire and Orthostatic Grading Scale (OGS). Results: Patients with OIS scored significantly higher on all three questionnaires and showed significant differences in autonomic responses during orthostatic stress tests compared with non-OIS patients. Receiver operating characteristic curve analysis showed that the orthostatic score from the ODSS had moderate predictive value for the supine test (area under the curve [AUC] = 0.754). Further subgroup analysis revealed that the orthostatic score from the ODSS had uniquely high specificity and sensitivity for identifying patients with orthostatic hypotension with abnormal cerebral blood flow (OH-U, AUC = 0.919). Conclusions: We conclude that the Chinese version of the ODSS has sufficient reliability and validity to distinguish patients with OIS and could possibly be used as a diagnostic tool for OH-U patients. Thus, the Chinese ODSS offers a beneficial screening tool for quickly assessing whether patients have OIS that requires further clinical assessment.
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Since China possesses the vast territory and a large blueberry planting area, blueberry harvesting with hand is laborious and time consuming. As the blueberry planting agronomy in China is different from other countries, it is pretty significant to develop blueberry harvesting machinery applicable to the domestic planting agronomy to achieve mechanized harvesting of blueberries. In blueberry harvesting operation, the harvesting system as the core component of the machine is the key technology of the harvesting machinery. The previous study found that: in terms of harvesting machinery, most of the literature has studied the dynamic characteristics, while few articles have been published to study the transmission clearance. But the clearance collision force generated by the transmission clearance of the harvesting system directly affected the output load moment and harvesting force of the machine developed by acting on the plant, and then affected the picking efficiency and the quality of picked fruit. Therefore, this paper focuses on the study of the transmission clearance of the blueberry harvesting machine. Firstly, the MLSD modeling method was applied to establish the transmission clearance model of the harvesting device, and the corresponding mechanical analysis of the transmission clearance was carried out. Secondly, after programming in MATLAB software and simulation in ADAMS software, the correctness of the transmission clearance model of the harvesting device was verified in different environments. The multi-body dynamics analysis software ADAMS was used for building the transmission clearance model of the harvesting device and perform mechanical simulation to analyze the clearance collision force and the output load moment of the harvesting device. Pro/E, ADAMS and ANSYS software were integrated to establish the flexible body of blueberry plant. Then the flexible body was combined with the mechanical model of harvesting device for rigid-flexible coupling simulation analysis to study the fruit harvesting force under different transmission clearances. Finally, the orthogonal method was used to conduct field test on blueberry harvesting to study the influence of the transmission clearance on the quality of picked fruit and picking efficiency of the machinery. Therefore, the best combination of the transmission clearance of the harvester was obtained as follows: cam clearance (the clearance joints of cam) was 0.25 mm, the slider clearance was 0.2 mm, left connecting rod clearance pair was 0.1 mm, right connecting rod clearance pair was 0.2 mm; the field picking test was conducted to obtain the machine's picking efficiency was 3.93 kg min-1, the shedding rate of unripe fruit was 3.1 %, and the damage rate of picked fruit was 2.8 %. The research findings of this paper can offer referenced basis and theoretical support for berry harvesting machinery, and also can provide guidance for the design and improvement of other agricultural and forestry harvesting machinery.
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Rapid antigen test (RAT) is widely used for SARS-CoV-2 infection diagnostics. However, test sensitivity has decreased recently due to the emergence of the Omicron variant and its sublineages. Here we developed a panel of SARS-CoV-2 nucleocapsid protein (NP) specific mouse monoclonal antibodies (mAbs) and assessed their sensitivity and specificity to important SARS-CoV-2 variants. We identified seven mAbs that exhibited strong reactivity to SARS-CoV-2 variants and recombinant NP (rNP) by Western immunoblot or ELISA. Their specificity to SARS-CoV-2 was confirmed by negative or low reactivity to rNPs from SARS-CoV-1, MERS, and common human coronaviruses (HCoV-HKU1, HCoV-CO43, HCoV-NL63, and HCoV-229E). These seven mAbs were further tested by immunoplaque assay against selected variants of concern (VOCs), including two Omicron sublineages, and five mAbs (F461G13, F461G7, F459G7, F457G3, and F461G6), showed strong reactions, warranting further suitability testing for the development of diagnostic assay.
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The COVID-19 pandemic poses ongoing challenges to the sustainability of various socioeconomic sectors, including agriculture, the food supply chain, the food business, and environmental sustainability. This study employs data obtained from the World Health Organization (WHO), and Food and Agriculture Organization (FAO), as well as scientific and technical research publications, to evaluate the impacts of COVID-19 on agriculture and food security. This article seeks to highlight the profound influence of the COVID-19 pandemic on agriculture, the supply and demand of food, and the overall safety of food. The article also explores the several pathways by which COVID-19 can be transmitted in these areas and the various technologies employed for its detection. The ongoing and post-pandemic ramifications are substantial since they could decrease agricultural output due to limitations on migration, a downturn in international trade, less buying capacity, and disturbances in food production and processing. Therefore, based on this thorough investigation, recommendations are issued for mitigating and controlling the pandemic's effects.
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Prior research has primarily focused on Atterberg limits, void ratios, and/or water content, often disregarding the impact of coarse material percentage in the soil, which significantly affects compressibility behavior. This paper examines the effects of sand content, initial degree of saturation, and initial dry unit weight on the compressibility behavior of expansive soils. Ninty-six oedometer tests were performed in order to accurately predict the compressibility behavior of expansive soils. The previous studies have attempted to correlate compressibility with different index properties separately, but no single study has taken into consideration all properties influencing compressibility behavior, especially for expansive soils. The findings show that compressibility is greatly influenced by the sand content, initial degree of saturation, and initial dry unit weight. Increasing the initial dry unit weight specifically lowers the compression index and permeability while raising the recompression index for the same percentage of added sand. Moreover, since swelling reduces with increasing initial saturation, raising the saturation degree also lowers the permeability, recompression index, and compression index. The results indicate that a sand content of more than 30 % is recommended for achieving desired properties in expansive clayey soil. This is a result of sand taking the dominant role in the soil mixture, which lowers soil suction and improves soil properties by reducing swelling, permeability, and compressibility. Symbolic regression equations were created to predict the compression and recompression indices, outperforming previous models in accurately predicting the compressibility behavior of expansive soils, considering the percentage of sand. The validation of these equations demonstrates their predictive capabilities.
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Background: Helicobacter pylori (H. pylori) is a significant global health concern, posing a high risk for gastric cancer. Conventional diagnostic and screening approaches are inaccessible, invasive, inaccurate, time-consuming, and expensive in primary clinics. Objective: This study aims to apply machine learning (ML) models to detect H. pylori infection using limited laboratory parameters from routine blood tests and to investigate the association of these biomarkers with clinical outcomes in primary clinics. Methods: A retrospective analysis with three ML and five ensemble models was conducted on 1409 adults from Hubei Provincial Hospital of Traditional Chinese Medicine. evaluating twenty-three blood test parameters and using the C 14 urea breath test as the gold standard for diagnosing H. pylori infection. Results: In our comparative study employing three different feature selection strategies, Random Forest (RF) model exhibited superior performance over other ML and ensemble models. Multiple evaluation metrics underscored the optimal performance of the RF model (ROC = 0.951, sensitivity = 0.882, specificity = 0.906, F1 = 0.906, accuracy = 0.894, PPV = 0.908, NPV = 0.880) without feature selection. Key biomarkers identified through importance ranking and shapley additive Explanations (SHAP) analysis using the RF model without feature selection include White Blood Cell Count (WBC), Mean Platelet Volume (MPV), Hemoglobin (Hb), Red Blood Cell Count (RBC), Platelet Crit (PCT), and Platelet Count (PLC). These biomarkers were found to be significantly associated with the presence of H. pylori infection, reflecting the immune response and inflammation levels. Conclusion: Abnormalities in key biomarkers could prompt clinical workers to consider H. pylori infection. The RF model effectively identifies H. pylori infection using routine blood tests, offering potential for clinical application in primary clinics. This ML approach can enhance diagnosis and screening, reducing medical burdens and reliance on invasive diagnostics.
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Introduction: Suicide risk assessment based on self-report questionnaires is considered as problematic because risk states are dynamic and at-risk individuals may conceal suicidal intentions for several reasons. Therefore, recent research efforts increasingly focus on implicit risk markers such as the suicide attentional bias (SAB) measured with the Suicide Stroop Task (SST). However, most SST studies failed to demonstrate a SAB in individuals with suicide risk and repeatedly demonstrated insufficient psychometrics of the SST. This study aimed to investigate a SAB using a modified SST (M-SST) and to test its psychometric properties. Method: We compared n = 61 healthy controls and a high-risk inpatient sample of n = 40 suicide ideators and n = 40 suicide attempters regarding interference scores of positive, negative and suicide-related words. Interference scores were calculated by subtracting the mean reaction time (mean RT) of the neutral words from the mean RT of the suicide-related words (mean RT Suicide -mean RT Neutral), resulting in a suicide-specific interference score. Similarly, interference scores were calculated for the positive and negative words by subtracting the mean RT of neutral words from the mean RT of positive and negative words. Results: A Group × Interference ANOVA showed a significant interaction effect (p <.001, ηp2 = .09), indicating that group effects significantly vary across interference type. Post hoc comparisons revealed that both ideators and attempters demonstrated greater interferences only for suicide-related words compared to healthy controls, indicating a SAB in patients, while a difference between ideators and attempters was lacking. The suicide interference score classified with an AUC = 0.73, 95% CI [0.65 - 0.82], p <.001, between controls and patients with STBs. The M-SST demonstrated good internal consistency and convergent validity. Discussion: The study adds evidence to the assumptions of the Cognitive Model of Suicide, viewing a SAB as a cognitive marker of suicide vulnerability independently of the engagement in suicidal behavior. The results' clinical implications are discussed in the context of recommended intervention strategies during an acute suicidal state. Future studies with the M-SST should include non-suicidal patient controls to investigate whether a SAB is uniquely related to suicidality.
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Objective: To retrospectively analyze clinical features in adolescent Menière's disease (MD). Methods: The medical records of adolescents with MD (11-17 years old) from May 2014 to March 2023 in Shandong Provincial ENT Hospital were retrospectively analyzed, including clinical features, a battery of auditory and vestibular function tests, sensory organization test, and imaging assessments. Patients with recurrent vertigo of childhood (RVC) were as controls. Results: Compared with RVC, adolescent MD showed higher pure tone average threshold (p < .001), lower speech discrimination score (p = .014), and lower otoacoustic emission pass rates (p = .005). Adolescents with MD exhibited significant reduction in equilibrium score (Conditions 1, 5, and 6; p1 = .035; p5 = .033; p6 = .003), composite sensory score (p = .014), and vestibular sensory score (p = .029). Adolescents with bilateral MD exhibited worse performance in equilibrium score and strategy score compared to adolescents with unilateral MD. For the affected ear, the more severe endolymphatic hydrops detected by gadolinium-enhanced magnetic resonance imaging, the higher the auditory brainstem response threshold (r = .850, p = .007), and the lower the otoacoustic emission pass rate (r = -.976, p < .001). Conclusion: Adolescent MD has similar vestibular information inputs with that of RVC, but the ability for the nerve center to use these clues to maintain balance is worse in adolescents with MD. There were potential differences in vestibular weights in adolescents with unilateral and bilateral MD, also potential effects on vision and proprioception. Level of Evidence: Level 4.
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BACKGROUND: The incidence of colorectal cancer (CRC) in China is steadily rising, with a high proportion of advanced-stage diagnoses. This highlights the significance of early detection and prevention measures to enhance survival rates. Fecal immunochemical testing (FIT) is a globally recommended CRC screening method; however, limited research has been conducted on its application in Hainan. AIM: To assess the efficacy and adherence of FIT screening among average-risk individuals in Hainan, while also examining the risk factors associated with positive FIT results. METHODS: This population-based cross-sectional study implemented FIT screening for CRC in 2000 asymptomatic participants aged 40-75 years from five cities and 21 community health centers in Hainan Province. The study was conducted from August 2022 to April 2023, employing a stratified sampling method to select participants. Individuals with positive FIT results subsequently underwent colonoscopy. Positive predictive values for confirmed CRC and advanced adenoma were calculated, and the relationship between relevant variables and positive FIT results was analyzed using χ 2 tests and multivariate logistic regression. RESULTS: A total of 1788 participants completed the FIT screening, with a median age of 57 years (interquartile range: 40-75). Among them, 503 (28.1%) were males, and 1285 (71.9%) were females, resulting in an 89.4% compliance rate for FIT screening. The overall positivity rate of FIT was 4.4% [79 out of 1788; 95% confidence interval (CI): 3%-5%]. The specific positivity rates for Haikou, Sanya, Orient City, Qionghai City, and Wuzhishan City were 9.6% (45 of 468; 95%CI: 8%-11%), 1.3% (6 of 445; 95%CI: 0.1%-3.1%), 2.7% (8 of 293; 95%CI: 1.2%-4.3%), 3.3% (9 of 276; 95%CI: 1.0%-6.3%), and 4.2% (11 of 406; 95%CI: 1.2%-7.3%), respectively. Significant associations were found between age, dietary habits, and positive FIT results. Out of the 79 participants with positive FIT results, 55 underwent colonoscopy, demonstrating an 82.2% compliance rate. Among them, 10 had a clean gastrointestinal tract, 43 had polyps or adenomas, and 2 were confirmed to have CRC, yielding a positive predictive value of 3.6% (95%CI: 0.9%-4.2%). Among the 43 participants with polyps or adenomas, 8 were diagnosed with advanced adenomas, resulting in an advanced adenoma rate of 14.5% (95%CI: 10.1%-17.7%). CONCLUSION: In the Hainan region, FIT screening for CRC among asymptomatic individuals at average risk is feasible and well-received.
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Colorectal cancer is one of the predominant tumors in the world, primarily generated by a progression from polyp to cancer which can last several years, giving a great opportunity to the scientific community for its prevention by screening programs that can be done with invasive and non-invasive tests. In this issue, Lopes et al show us an excellent review of screening, its options, its advantages and disadvantages.
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Introduction: Recent studies have emphasized the intricate connection between exercise and cognition, focusing on specific cognitive processes and their correlations with specific motor skills. However, research on the impact of the qualitative aspects of movement on both short- and long-term cognitive performance is limited. In this quasi-experimental study, we investigate the impact of a 10-week fancy rope-skipping intervention on motor coordination and selective attention of 7-9-year-old children. Methods: A total of 60 primary school students from Changbin School in Haikou participated and completed the study from October to December 2022. The 60 participants were divided into a fancy rope-skipping group and a control group. Children's motor coordination was assessed using the Körperkoordinations Test für Kinder (KTK), while selective attention was evaluated using the d2 Test of Attention. Children were assessed at baseline and after the 10-week intervention. Results: Compared with the control group, the scores for the total KTK and for the hopping for height, jumping sideways, and moving sideways sub-items were significantly higher in the rope-skipping group after the intervention, with a significant interaction effect between time and intervention. Attention concentration improved in the rope-skipping group and had a significant interaction effect between time and intervention compared with the control group; the effects of the intervention on other aspects of selective attention were unclear. Conclusions: Our study suggests that a 10-week fancy rope-skipping intervention may potentially enhance motor coordination and selective attention accuracy in children aged 7-9 years.
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Introduction: Klebsiella pneumoniae (K. pneumoniae) is the most common pathogen causing hospital respiratory tract infection and epidemic. Gold standard procedures of microscopic examination and biochemical identification are widely used in clinical diagnosis with disadvantages of low sensitivity, time-consuming and sophisticated equipment requiring. An efficient, nucleic acid amplification-based sensitive and specific on-site identification of K. pneumoniae in clinical is necessary to facilitate clinical medication and disease control. Methods: We developed a closed dumbbell mediated isothermal amplification (CDA) assay for the rapid and sensitive detection of conserved rcsA gene in K. pneumoniae by real-time fluorescence monitoring and end-point colorimetric judgement. We designed and selected a pair of inner primers of CDA to detect K. pneumoniae. Then outer and loop primers were designed and verified to accelerate CDA reaction to achieve more efficient detection of K. pneumoniae. Results: The results showed the detection limit of CDA assay was 1.2 × 10-5 ng/µL (approximately 1 copy of the target gene) within 60 min, which was 100-fold more sensitive than real-time quantitative PCR (qPCR). Several pathogen genomic DNAs (Staphylococcus aureus, Shigella sonnei, Vibrio parahaemolyticus, Escherichia coli, Candida glabrata, Candida tropicalis, Candida parapsilosis, Candida albicans, Streptococcus agalactiae, Rickettsia, Listeria monocytogenes, Pseudomonas aeruginosa, Klebsiella oxytoca, and Klebsiella aerogenes) were used to evaluate the sensitivity and specificity of the established K. pneumoniae CDA assay. Total 224 batches of samples from other strains tested were negative and 296 batches of extracted K. pneumoniae DNA samples were positive by the developed CDA amplification approach, revealing high specificity and specificity of the diagnostic assay. In addition, the results of real-time fluorescence amplification of the K. pneumoniae CDA were in consistent with those of end-point colorimetric results. Discussion: The established real-time fluorescence and visual CDA assays of K. pneumoniae with merits of rapid, sensitive and specificity could be helpful for on-site diagnosis and clinical screening in rural areas.
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AIMS: The gold standard clamp measurements for insulin sensitivity (cSI), ß-cell function (cBCF) and disposition index (cDI = cSI*cBCF), are not practical in large-scale studies. We sought to: 1) validate a mathematical model-derived DI from oral glucose tolerance tests (OGTT) with insulin (mDI) and without (mDI-woI) against cDI and oral disposition index (oDI) evaluate the ability of the novel indices to detect prediabetes and type 2 diabetes. METHODS: We carried out a secondary analysis of previously reported cross-sectional observational studies. The Insulin Sensitivity and Secretion mathematical model for glucose-insulin dynamics was applied to five-point and three-point OGTTs synchronized with hyperinsulinemic-euglycemic and hyperglycemic clamps from 130 youth with obesity (68 NGT, 33 IGT, 29 T2D). RESULTS: Model-derived DI correlated well with clamp DI (R = 0.76 (logged)). Between NGT and IGT, mDI and mDI-woI decreased more than oDI and cDI, (60 and 59% vs 29 and 27%), and by receiver operating characteristic (ROC) analysis were superior at detecting IGT than oDI and cDI (AUC 0.88, 0.87 vs 0.68, 0.65), as was mean glucose (AUC 0.87). CONCLUSIONS: mDI-woI is better than oDI or the labor-intensive cDI for detecting dysglycemia in obese youth. Bypassing insulin measurements with mDI-woI from the OGTT provides a cost-effective approach for large-scale epidemiological studies of dysglycemia in youth.
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Water constitutes the most prevalent impurity in organic solvents, exerting significant influence on chemical reactions and potentially leading to fires and explosions, even in minute quantities. Thus, the development of convenient, rapid, and cost effective fluorescent probes for real-time monitoring of water content in organic solvents is imperative. Although some fluorescent materials have been synthesized for this purpose, most suffer from laborious preparation processes and poor cycling performance, constraining their practical application. This study investigates the impact of hydrogen bonding on the aggregation-induced emission (AIE) properties of quinoline derivatives, leveraging quinoline as the foundational scaffold and its nitrogen atom as the hydrogen bond acceptor. Research findings elucidate that intermolecular hydrogen bonding of quinoline is the primary determinant of their AIE behaviors. By harnessing the phenomenon of water molecules forming intermolecular hydrogen bonds with quinoline nitrogen atoms, we devised a straightforward and rapid method to fabricate a fluorescent test paper for real-time monitoring of water content in organic solvents. Experimental results demonstrate that even minute changes in water content, down to concentrations as low as 0.5 % by volume in organic solvents, can induce fluorescence changes in the test paper, which also exhibits favorable cycling performance. This study not only explores the influence of hydrogen bonds on the AIE properties of quinoline derivatives but also pioneers the development of a cost-effective, rapid, and recyclable test paper for real-time monitoring of water content fluctuations in organic solvents.
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A rapid user-friendly paper-based test strip using zinc microparticles in conjugation with Griess reagent was developed for nitrite and nitrate detection. Test strips were fabricated using a simple and fast method of step-by-step immersion into reagents so that each strip contained a single detection pad for nitrite detection and another separate pad for nitrate detection. To reduce nitrate to nitrite, zinc microparticles suspended in ethanolic solution of polyvinylpyrrolidone (PVP) were uniformly immobilized on the paper strips that were previously impregnated in the Griess reagent and dried. The Griess reagent components were optimized to reach the highest color intensity. The optimized test strip was able to determine both nitrite and nitrate with respective detection limits of 0.43 and 9.43 mg/kg and a detection time of 60 s. The performance of the new test strips was evaluated for the simultaneous colorimetric detection of nitrite and nitrate in water and different food samples.
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To evaluate the measurement accuracy of horizontal and vertical remote emission sensing (RES) equipment, a real-world dynamic test was carried out in Chengdu by using electric vehicles equipped with various concentrations of standard gases. In addition, a new vertical remote sensing spectral data algorithm based on image processing (ISPA) was developed to improve the measurement capability. The results showed that the ISPA provided a greater percentage of valid data and lower relative errors; thus, our new algorithm could more effectively analyze the spectral data to measure vehicle emission levels. The percentages of valid horizontal and vertical RES data were 71% and 84%, respectively. The mean relative errors of CO2, CO, HC and NO measured by the vertical RES were about 5%, 20%, 20% and 40%, respectively, and those of CO2, CO and NO measured by the horizontal RES were 3%, 13% and 15%, respectively. For the common vehicle emission concentration, the percentage of valid data for the two RES types increased with increasing gas concentration. As the vehicle speed increased, the relative errors of the horizontal RES equipment showed an increasing trend for the same concentration of gas. Furthermore, for the same speed segment, the relative errors of the horizontal RES equipment increased as the simulated emission concentration decreased. The vertical RES equipment did not exhibit a consistent trend in terms of changes. This study provides a data quality reference for further RES applications.