In the field of diagnostic test accuracy (DTA), the use of systematic review and meta-analyses is steadily increasing. By means of objective evaluation of all available primary studies, these two processes generate an evidence-based systematic summary regarding a specific research topic. The methodology for systematic review and meta-analysis in DTA studies differs from that in therapeutic/interventional studies, and its content is still evolving. Here we review the overall process from a practical standpoint, which may serve as a reference for those who implement these methods.
Databases, Factual ; Diagnostic Tests, Routine/*standards ; Humans ; ROC Curve ; Research

To explore the value of items for the Chinese version of Dizziness Handicap Inventory (DHI) in differential diagnosis of benign paroxysmal positional vertigo (BPPV) in patients with vertigo or dizziness first coming to the outpatient clinic.
 Methods: A total of 322 patients with vertigo or dizziness, who came from Nanfang Hospital, Southern Medical University, were enrolled from April 2016 to February 2017. The Chinese version of DHI and Visual Analogue Scale (VAS) were completed by themselves. After detailed vestibular function examination, the patients were divided into a BPPV group, a normal vestibular group, and a abnormal vestibular group.
 Results: The score of DHI-2 in the BPPV group was 5.52±2.10, which was higher than that in the normal vestibular group (3.94±2.91)(t=3.847, P<0.01) and the abnormal vestibular group (4.17±2.74)(t=4.149, P<0.01). There were significant differences in the DHI-2 among the 3 groups (F=9.870, t=4.515, P<0.01). The score of DHI-item 13 in the BPPV group was 3.09±1.39, which was higher than that in the normal vestibular group (1.97±1.63)(t=4.515, P<0.01) and the abnormal vestibular group (1.95±1.70)(t=5.305, P<0.01). There were significant differences in the DHI-item 13 among the 3 groups (F=16.402, P<0.01). There was significant difference in VAS scores among the 3 groups (P<0.05). However, the t-test analysis showed that there was significant difference between the BPPV group and the vestibular abnormal group (P<0.05), while there was no significant difference between the BPPV group and the vestibular normal group (P>0.05).
 Conclusion: DHI-2 and DHI-item 13 should be included in the inquiry of disease history at the time of first diagnosis, which can be used to identify patients with BPPV quickly and effectively.
Benign Paroxysmal Positional Vertigo ; diagnosis ; Diagnosis, Differential ; Diagnostic Tests, Routine ; standards ; Dizziness ; diagnosis ; Humans

This paper introduced the Revised Tool for the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2), including the development and comparison with the original QUADAS, and illustrated the application of QUADAS-2 in a published paper related to the study on diagnostic accuracy which was included in systematic review and Meta-analysis. QUADAS-2 presented considerable improvement over the original tool. Confused items that included in QUADAS had disappeared and the quality assessment of the original study replaced by the rating of risk on bias and applicability. This was implemented through the description on the four main domains with minimal overlapping and answering the signal questions in each domain. The risk of bias and applicability with 'high','low' or 'unclear' was in line with the risk of bias assessment of intervention studies in Cochrane, so to replace the total score of quality assessment in QUADAS. Meanwhile, QUADAS-2 was also applicable to assess the diagnostic accuracy studies in which follow-up without prognosis was involved in golden standard. It was useful to assess the overall methodological quality of the study despite more time consuming than the original QUADAS. However, QUADAS-2 needs to be modified to apply in comparative studies on diagnostic accuracy and we hope the users would follow the updates and give their feedbacks on line.
Bias ; Diagnostic Tests, Routine/standards* ; Humans ; Quality Assurance, Health Care ; Research Report ; Risk

OBJECTIVETo introduce Meta-analysis in evaluating diagnostic tests.

METHODAdjusted SROC method was used in assessing 7 diagnostic tests on fatty liver.

RESULTSThe pooled sensitivity and specificity of type B ultrasonography were 0.89 [95% confidence interval (CI): 0.87-0.92] and 0.94 (95% CI: 0.92-0.96) respectively while the Q value was 0.90 by adjusted SROC method. The results indicated that the diagnostic value of type B ultrasonography were high, thus could be regarded as an effective method for fatty liver diagnosis.

CONCLUSIONMeta-analysis on evaluating diagnostic tests could be used to assess the diagnostic test to increase the power of conclusion, and to improves its reliability.

Diagnostic Tests, Routine ; standards ; Evaluation Studies as Topic ; Fatty Liver ; diagnosis ; diagnostic imaging ; Humans ; Liver ; diagnostic imaging ; Predictive Value of Tests ; Sensitivity and Specificity ; Ultrasonography

BACKGROUNDAtopic dermatitis (AD) is a common inflammatory skin disease with an increasingly significant prevalence. The prevalence of AD depends greatly on how its diagnosis is done. The UK Working Party's diagnostic criteria for AD are simple and easy to apply without invasive laboratory tests. This study assessed the clinical utility of these criteria in China.

METHODSData were collected from 6208 patients at 31 tertiary hospitals in 13 Chinese provinces/municipalities from March 2014 to May 2014. . The agreement between the UK diagnostic criteria and the clinical records for AD was assessed by Cohen's kappa.

RESULTSThe overall agreement between the UK diagnostic criteria and clinical diagnosis was fair (kappa = 0.40). A slightly better agreement was found in patients aged between 4 and 9 years (kappa = 0.48), while fair agreement was found in the group <4 years and the group ≥10 years (kappa = 0.27 and 0.39, respectively). Using the UK party's criteria as the standard, the sensitivity, specificity, positive predictive value, and negative predictive value of the clinical diagnosis of AD were 62.3%, 89.2%, 38.0%, and 95.7%, respectively.

CONCLUSIONSOur study indicates a modest ability among Chinese dermatologists to apply the UK Working Party's diagnostic criteria for AD, especially in patients aged <4 years and ≥10 years. Since there is no gold standard for AD diagnosis, it is important to determine how AD is identified when evaluating a diagnostic tool.

Adult ; Age Factors ; Child ; Child, Preschool ; China ; Dermatitis, Atopic ; diagnosis ; Diagnostic Tests, Routine ; methods ; standards ; Female ; Humans ; Male ; Middle Aged ; Predictive Value of Tests ; Reproducibility of Results ; United Kingdom

To establish a novel colloidal gold immunochromatography assay (GICA) for rapid, sensitive and accurate detection of Haemophilus influenzae infection by using the outer membrane protein P6 as detection target. First, the linear antigen epitope located in the extracellular domain of the P6 protein (GenBank accession number: AGH02799) was predicted by bioinformatics analysis. The region (62-75 aa of the protein) with strong antigen specificity was chosen and synthesized. Two rabbits were then immunized by the polypeptides (14 aa) for production of polyclonal antibodies. Then, the recombinant P6 proteins were also obtained to produce polyclonal antibodies. Finally, based on the two antibodies, a novel colloidal GICA for detection of Haemophilus influenzae infection was established and the specificity, sensitivity, repeatability and stability of this method were evaluated. At the same time, the method was tested in clinical simulation, and the plate culture method was used to verify its accuracy. The test strip for Haemophilus influenzae infection was successfully prepared. The detection limit of the test strip was as low as 1×105 CFU/mL and the whole process can be completed within 15 minutes. The strip specifically recognized Haemophilus influenzae and did not react with nine of other common respiratory pathogens such as Streptococcus pneumoniae, Moraxella catarrhalis, Mycoplasma pneumonia, and Legionella pneumophila. And the strips could be stored at 25 °C for at least 6 months without losing sensitivity or specificity. The coincidence rate between the results of 200 clinical samples and the plate culture method was 90.5%. Haemophilus influenzae protein P6, which possessed a high degree of surface antigen accessibility and antigencity, could be used as a marker for Haemophilus influenzae detection. The immunochromatographic colloidal gold test strip which bears the features of rapidity, convenience and sensitivity provides a unique tool for the on-site surveillance and diagnosis of Haemophilus influenzae infection in clinical test.
Animals ; Chromatography, Affinity ; instrumentation ; Diagnostic Tests, Routine ; standards ; Gold Colloid ; chemistry ; Haemophilus Infections ; diagnosis ; Haemophilus influenzae ; Humans ; Limit of Detection ; Rabbits ; Sensitivity and Specificity

OBJECTIVETo study the agreement between ophthalmologists and community health workers in detecting shallow anterior chamber with oblique flashlight test.

METHODSTotally 425 subjects were given an eye examination in a community health center. The anterior chamber depth of each subject was examined by one ophthalmologist and two trained community health workers (one nurse and one non-professional health worker) using oblique flashlight test. Inter-observer agreement was determined using the weighted kappa statistic.

RESULTSAmong the enrolled subjects, 148 (35%) were male and 277 (65%) were female. Good agreement was noted in all the three observers. The comparison between the ophthalmologist and the nurse showed a kappa statistic of 0.42 for both eyes (P < 0.001). The kappa statistic was 0.54 and 0.52 for right and left eyes respectively between the ophthalmologist and the non-professional health worker (P<0.001). As for agreement between the nurse and the non-professional health, worker, the kappa statistic was 0.49 and 0.38 for right and left eyes, respectively (P < 0.001).

CONCLUSIONThe oblique flashlight test may be used as an applicable tool by trained community health workers for screening of shallow anterior chamber and play a role in blindness prevention in community.

Adult ; Aged ; Aged, 80 and over ; Anterior Chamber ; anatomy & histology ; pathology ; Community Health Workers ; Diagnostic Tests, Routine ; standards ; Female ; Glaucoma, Angle-Closure ; diagnosis ; pathology ; Humans ; Light ; Male ; Middle Aged ; Ophthalmology ; manpower ; Photic Stimulation ; Risk Factors ; Sensitivity and Specificity ; Young Adult