Diagnosis is the critical component of health care and the studies of diagnostic test can provide important evidence for clinical decisions. Studies of diagnostic test are subject to different sources of bias in design, performance and reporting of studies. Therefore, researchers who understand various sources of bias can reasonably perform the diagnostic test and evaluate its quality, and will provide scientific evidences for clinical practice.
Objective To assess the quality of current domestic literature about enzyme-linked immunosorbent assay (ELISA) for invasive aspergillosis diagnosis by detecting Aspergillus galactomannan (GM) antigen, and to analyze the sources of bias and variability, as well as the diagnostic ability of different thresholds. Methods Both computer-based online search and manual retrieval were employed to identify relevant articles. The statistical information and quality of science were assessed and classified. The data were analyzed using Meta Disc 1.4 software. The best cutoff value for defining a positive test result was selected by summarizing the following statistical indicators as sensitivity, specificity, likelihood ratio (LR) and summary receiver operating characteristic curve (SROC curve), and by calculating the area under the curve (AUC) as well. Results A total of 20 studies among 2658 literatures were included in accordance with the inclusion criteria, and were divided into different groups based on different cutoff values. Though heterogeneity tests showed no threshold effect, and there were other reasons of heterogeneity. So the data were analyzed by random effects model. The results showed that, compared with other groups, the one with cutoff value set at 0.7 (AUC=0.9456, Q= 0.884 6) showed the best accuracy in diagnosing. Conclusion ELISA detection of Aspergillus GM antigen with cutoff value set at 0.7 has important significance in the early diagnosis of invasive aspergillosis, and it can be conducive to reduce mortality in patients at high risk for Aspergillus infection.
Objective To evaluate the diagnostic value of N terminal pro-brain natriuretic peptide (NT-proBNP) for heart failure (HF) and the relationship between NT-proBNP and HF. Methods Applying electrochemiluminescence immunoassay on Elecsys 2 010 quantitatively detects NT-proBNP in HF patients with varing heart damage. Results ① Using 155 pg/ml as the cutoff for diagnosis of HF, the sensitivity and specificity are both 80 %, positive likelihood ratio (PLR) is more than 4.0; when NT-proBNP is more than 350 pg/ml, PLR is more than 14. ② NT-proBNP significantly increases in HF patients，and has significant difference compared with disease control group, Plt;0.05. In dilated cardiomyopathy (DCMP) and acute myocardial infarction (AMI) NT-proBNP is the highest, in coronary heart disease (CHD) and hypertension it’s the smallest. With rising NYHA classes, NT-proBNP increases exponentially. The correlation between NT-proBNP and heart function is good, rs=0.859 (Plt;0.01). Conclusions NT-proBNP for diagnosing HF has a high sensitivity and specificity and can effectively evaluate heart function. With worsening of heart damage, NT-proBNP shows exponential or linear increase.
With the development of artificial intelligence, machine learning has been widely used in diagnosis of diseases. It is crucial to conduct diagnostic test accuracy studies and evaluate the performance of models reasonably to improve the accuracy of diagnosis. For machine learning-based diagnostic test accuracy studies, this paper introduces the principles of study design in the aspects of target conditions, selection of participants, diagnostic tests, reference standards and ethics.
Objective To review literatures regarding the diagnosis of asthma with the measurement of exhaled nitric oxide( eNO) and assess the effectiveness and accuracy of eNO in the diagnosis of asthma.Methods MEDLINE, OVID, CBMdisc, CNKI( 1991 to 2008) for studies involving the diagnostic value of eNO were searched, and references of included studies were also hand searched. QUADAS ( Quality Assessment of Diagnostic Accuracy Studies) items were used for quality assessment in the systematic review. Meta-disc software was used to analyze heterogeneity. Sensitivity, specificity and summary diagnostic odds ratio( SDOR) were used for the pooled analysis. The summary receiver operating characteristic ( SROC)curves were drew and the summary areas under the SROC ( SAUC) were calculated. Finally, sensitivity analysis was performed. Results Eleven literatures with15 studies were included. These 15 studies had well controlled the bias of partial verification, differential verification, incorporation and withdrawals. The possibility of the disease progression bias was less and the reference standard review could have a greater bias. The spectrumcomposition of a study, the inclusion and exclusion criteria and the reporting quality were poorly reported. In statistical analysis, the totally pooled sensitivity, pooled specificity, SDOR, SAUC of the measurement of eNO in the diagnosis of asthma was 0. 68, 0. 79, 12. 73, 0. 8446, respectively. Sensitivity analysis demonstrated no disproportionate influences of individual study. Conclusions eNO has a certain value in the diagnosis of asthma. To make further analysis, more studies with high quality are needed.
ObjectiveTo systematically review the value of mass screening of serum pepsinogen test for Asian population with high-risk gastric carcinoma. MethodsWe electronically searched databases including PubMed, EMbase, The Cochrane Library (Issue 12, 2013), CNKI, WanFang Data, VIP and CBM for diagnostic tests on serum pepsinogen test versus with pathological biopsy/X-ray examination (gold standard) between January 2004 and January 2014. Two reviewers independently screened literature according to the inclusion and exclusion criteria, extracted data, and assessed methodological quality of included studies. Then meta-analysis was conducted using Meta-DiSc software (version 1.4). ResultsA total of 15 studies involving 180 934 subjects were included. ROC curve showed "shoulder-arm shape" distribution. The results of Spearman correlation analysis suggested a significance of the threshold effect (P=0.001). The results of meta-analysis showed that, the area under curve (AUC) was 0.74. ConclusionSerum pepsinogen has good value in the screening of gastric carcinoma among Asian permanent residents. Due to limited quality of studies, the above conclusion should be verified by conducting more high quality studies.
Objective To evaluate the diagnostic value of all diagnostic tests detecting the ethambutol resistance in Mycobacterium tuberculosis. Methods PubMed, EMbase, Chinese Biomedical Database (CBM), Chinese Scientific Journals Full-Text Database (CSJD), and Chinese Journal Full-text Database (CJFD) were searched, and QUADAS items were used to evaluate the quality of included studies. Meta-disc software was used to handle data from included studies. Such index as sensitivity, specificity, and SROC were applied to assess the diagnostic value of individual diagnostic test. Results Nine studies were included. The results of meta-analyses showed that compared with proportion method, the summary sensitivity, summary specificity, positive likelihood ratio, negative likelihood ratio, and SROC area under curve of a nitrate reductase assay were 92%, 99%, 30.50, 0.13, and 0.975 2, respectively, while compared with BACTEC 460 TB, the above mentioned indexes of BACTEC MGIT 960 System were 92%, 99%, 6.27, 0.11, and 0.9, respectively. Bacteriophage biological amplification method revealed relative good analysis effectiveness on MB/BacT. Conclusion According to the results, it is recommended that nitrate reductase assay can replace proportion method as screening test of ethambutol resistance in Mycobacterium tuberculosis, and BACTEC MGIT 960 System can replace BACTEC 460 as final diagnostic test of ethambutol resistance in Mycobacterium tuberculosis.
ObjectiveTo systematically review the accuracy of the mini-mental state examination scale (MMSE) in the screening of poststroke cognitive impairment (PSCI), and the diagnostic value of different cut-off values of the scale, so as to provide references for the selection of the threshold of the MMSE scale. MethodsDatabases including PubMed, EMbase, Cochrane Library, Web of Science, CINAHL, CBM, VIP, CNKI, and WanFang data were searched for diagnostic tests about MMSE for PSCI from inception to November 2022. Two researchers independently screened the literatures, extracted data and assessed the risk of bias of the included studies. Then, meta-analysis was performed by Stata 16.0 software. ResultsA total of 23 studies involving 1 525 patients were included. The results of meta-analysis showed that after the analysis of bivariate mixed effect model, the optimal cutoff value of MMSE scale was 23/24 (the pooled sensitivity=0.75, 95%CI 0.52 to 0.89; the pooled Specificity=0.90, 95%CI 0.81 to 0.95; DOR=28, 95%CI 12 to 65; AUC=0.92, 95%CI 0.89 to 0.94). The results of hierarchical summary receiver-operating characteristic (HSROC) curve model showed that the pooled sensitivity=0.77, 95%CI 0.70 to 0.83; the pooled specificity=0.76, 95%CI 0.69 to 0.83, Beta=0.1, 95%CI ?0.13 to 0.33, Z=0.82, P=0.41, Lambda=2.38, 95%CI 2.12 to 2.64, and the area under the SROC curve was 0.84. Fagan pre-test probability was 38%, positive likelihood ratio was 3.3, positive post-test probability was 67%, negative likelihood ratio was 0.3,negative post-test probability was 16%. ConclusionThe current evidence shows that MMSE has a certain diagnostic value as a screening tool for PSCI, the overall diagnostic efficacy is moderate, and the diagnostic value is highest when the cut-off value is 23/24. Due to the limited quality and quantity of the included studies, more high quality studies are required to verify the above conclusion.
Objective To evaluate the diagnostic value of ELISA using AgB in cystic echinococcosis (CE). Methods Such databases as PubMed, EMbase, The Cochrane Library, EBSCO, CBM, CNKI, WanFang Data and MedaLink were retrieved on computer, and the relevant journals were also manually searched to collect the trials on ELISA using AgB in diagnosis of CE. The retrieval time was from inception to July 5th, 2012. Two reviewers independently screened the literature, extracted the data and assessed the quality according to QUADAS. Then the meta-analysis was conducted by using Meta-Disc 1.4 software. Results A total of 8 studies were included, and there were 562 CE patients diagnosed by gold standard, 434 suspected cases and 303 healthy people. There were no threshold effects among those 8 studies (the spearman’s correlation coefficient of log sensitivity to log 1-specificity was 0.527, P=0.400 1). The meta-analysis of DerSimonia-Laird showed that, the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio was 0.76 (95%CI 0.73 to 0.79), 0.84 (95%CI 0.82 to 0.86), 5.20 (95%CI 3.59 to 7.55), 0.26 (95%CI 0.18 to 0.35), 23.93 (95%CI 12.35 to 46.39), respectively. And the AUC of SROC was 0.889 7 (Q=0.820 4). Conclusion ELISA using natural AgB and rAgB has greater diagnostic value in detecting CE.
ObjectiveTo systematically review the differential diagnostic value of contrast-enhanced ultrasound (CEUS) and contrast-enhanced CT (CECT) for renal solid space-occupying lesions. MethodsDatabases including EMbase, PubMed, The Cochrane Library (Issue 11, 2014), CNKI, CBM, VIP and WanFang Data were searched for diagnostic tests about CEUS and CECT for renal solid space-occupying lesions from inception to September, 2014. Two reviewers independently screened literature, extracted data and assessed the methodological quality of included studies. Then meta-analysis was performed using Meta-Disc 1.4 software. ResultsA total of 13 studies involving 754 specimens were included. The results of meta-analysis showed that:the sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio (combined effect and its 95%CI) in the CEUS group were 0.96 (95%CI 0.94 to 0.97), 0.77 (95%CI 0.70 to 0.83), 3.82 (95%CI 2.93 to 4.97), 0.06 (95%CI 0.04 to 0.10), 64.33 (95%CI 36.79 to 112.51), and in the CECT group were 0.84 (95%CI 0.81 to 0.87), 0.73 (95%CI 0.65 to 0.79), 2.81 (95%CI 2.22 to 3.56), 0.23 (95%CI 0.16 to 0.34), 13.85 (95%CI 6.79 to 28.26). There were significant differences between the CEUS group (0.960 8, 95%CI 0.927 3 to 0.994 3) and the CECT group (0.866 8, 95%CI 0.788 8 to 0.944 8) in the area under the summary receiver operating characteristic (SROC) curve (P<0.05). The similar results were observed in cases with small renal tumors≤4 cm (AUC:0.973 7 vs. 0.861 3, P<0.05). ConclusionCEUS has higher differential diagnostic value than CECT for renal solid space-occupying lesions.