Bayes theorem diagnosis

OBJECTIVES: This study compared the diagnostic accuracy of pretreatment circulation collateral scoring (CS) system using digital subtraction angiography (DSA) and computed tomography angiography (CTA) in predicting favorable functional outcome (FFO) after intra-arterial endovascular thrombectomy (IA-EVT). Subgroup analysis characterizing scoring systems within each category was additionally conducted. MATERIALS AND METHODS: We performed a diagnostic meta-analysis to assess the sensitivity and specificity of each CS system by using DSA and CTA, respectively...

Diagnostic tests for allergy usually are performed to confirm a diagnosis of an allergic disease. If a food allergy suspected, a test can help to determine whether it is present, to monitor its activity over time, and to determine whether the allergy is resolving. In this way, tests are used for diagnosis, monitoring, screening, and prognosis. There are 2 schools of thought for using tests: Frequentist and Bayesian approaches. The Frequentist approach defines probability in terms of the frequency of an event if it were to be repeated numerous times and uses parameters such as sensitivity, specificity, and predictive values to make a diagnosis...

OBJECTIVES: The majority of lung cancer cases are of advanced stage and diagnosis is usually made using minimally invasive small biopsies and cytological specimens. The WHO'2015 classification recommends limiting immunocytochemistry(ICC) to lung cancer typing and molecular testing drives for personalized therapies. An algorithm using Bayes' theorem could be useful for defining antibody profiles. This study aims to assess the impact of using different antibody profiles for cytological samples on the accuracy of lung cancer typing with a large scale Bayesian analysis...

The SARS-CoV-2 pandemic has created a demand for large scale testing, as part of the effort to understand and control transmission. It is important to quantify the error rates of test equipment under field conditions, which might differ significantly from those obtained in the laboratory. A literature review on SARS-CoV-2 reverse-transcription polymerase chain reaction (RT-PCR) is used to construct a clinical test confusion matrix. A simple correction method for bulk test results is then demonstrated with examples...

Establishing an accurate diagnosis is crucial in everyday clinical practice. It forms the starting point for clinical decision-making, for instance regarding treatment options or further testing. In this context, clinicians have to deal with probabilities (instead of certainties) that are often hard to quantify. During the diagnostic process, clinicians move from the probability of disease before testing (prior or pretest probability) to the probability of disease after testing (posterior or posttest probability) based on the results of one or more diagnostic tests...

OBJECTIVE: We define the prevalence threshold as the prevalence level below which a test's positive predictive value (PPV) declines most sharply relative to disease prevalence - and thus the rate of false positive results/false discovery rate increases most rapidly. The objective of this study is to determine the prevalence threshold of various screening tests used in obstetrics and gynecology among low-risk women in modern clinical practice. METHODS: We searched Medline, EMBASE, Google Scholar, Scopus, ISI Web of Science, Cochrane database, and PubMed to obtain the sensitivity and specificity estimates for the following screening tests: 50 g-oral glucose tolerance test (GDM-50 g), non-invasive prenatal testing (NIPT), combined first trimester screening (FTS), vagino-rectal swab for group B streptococcus (GBS) in pregnancy, cervical cytology (Pap) and HPV testing, mammography and manual breast exam, urinary PCR and cervical-vaginal swab testing for gonorrhoea and chlamydia as well as AMH for the diagnosis of PCOS...

OBJECTIVES: Positive predictive values (PPVs) and negative predictive values (NPVs) are frequently reported to put estimates of accuracy of a diagnostic test in clinical context and to obtain risk estimates for a given patient taking into account baseline prevalence in the population. In order to calculate PPV and NPV, tests with ordinally or continuously scaled results are commonly dichotomized at the expense of a loss of information. METHODS: Extending the rationale for the calculation of PPV and NPV, Bayesian theorem is used to calculate the probability of disease given the outcome of a continuously or ordinally scaled test...

Uveitis encompasses a heterogeneous group of clinical entities with the common feature of intraocular inflammation. In addition to patient history and examination, a focused set of laboratory investigations is frequently necessary to establish a specific diagnosis. There is limited consensus among uveitis specialists regarding appropriate laboratory evaluation for many distinct patient presentations. The appropriateness of a laboratory test for a given case of uveitis will depend on patient-specific as well as epidemiologic factors...

This paper aims to construct a Bayesian(BN) fault diagnosis model of traditional Chinese medicine dry granulation based on the failure model and effect analysis(FMEA), effectively control risk factors and ensure the quality of granules.Firstly, the risk ana-lysis of dry granulation process was carried out with FMEA, and the selected medium and high risk factors were taken as node variables to establish corresponding BN network with causality.According to the mathematical reasoning method of probability theory, the model was accurately inferred and verified by Netica, and the granule nonconformance was used as the evidence for reversed reasoning to determine the most likely cause of the failure that affected the granule quality...

BACKGROUND: It is essential to avoid admission of patients with undetected corona virus disease 2019 (COVID-19) to hospitals' general wards. Even repeated negative reverse transcription polymerase chain reaction (RT-PCR) results do not rule-out COVID-19 with certainty. The study aimed to evaluate a rule-out strategy for COVID-19 using chest computed tomography (CT) in adults being admitted to the emergency department and suspected of COVID-19. METHODS: In this prospective, single centre, diagnostic accuracy cohort study, consecutive adults (≥ 18 years) presenting with symptoms consistent with COVID-19 or previous contact to infected individuals, admitted to the emergency department and supposed to be referred to general ward were included in March and April 2020...

OBJECTIVE: Psychogenic non-epileptic seizures (PNES) are conversion disorders with functional neurological symptoms that can resemble epileptic seizures (ES). We conducted a systematic review to obtain an overview of the value of prolactin (PRL) levels in the differential diagnosis between PNES and ES. METHODS: We searched PubMed, EMBASE, and Cochrane Library databases for studies published up to June 4th, 2020. Published studies were included if they fulfilled the following criteria: original research on PRL changes after ES and PNES...

Tuberculous meningitis (TBM) is the most devastating form of tuberculosis (TB) but diagnosis is difficult and delays in initiating therapy increase mortality. All currently available tests are imperfect; culture of Mycobacterium tuberculosis from the cerebrospinal fluid (CSF) is considered the most accurate test but is often negative, even when disease is present, and takes too long to be useful for immediate decision making. Rapid tests that are frequently used are conventional Ziehl-Neelsen staining and nucleic acid amplification tests such as Xpert MTB/RIF and Xpert MTB/RIF Ultra...

PURPOSE: To quantify the risk of peritonsillar abscess (PTA) following consultation for respiratory tract infection (RTI) in primary care. METHOD: A cohort study was conducted in the UK Clinical Practice Research Datalink including 718 general practices with 65,681,293 patient years of follow-up and 11,007 patients with a first episode of PTA. From a decision tree, Bayes theorem was employed to estimate both the probability of PTA following an RTI consultation if antibiotics were prescribed or not, and the number of patients needed to be treated with antibiotics to prevent 1 PTA...

PURPOSE: The impact of smoking habits on periodontal treatment has not been clearly elucidated. This study aimed to specify the effects of cigarette consumption and nicotine addiction on periodontal therapy. MATERIALS AND METHODS: In this retrospective case-control study, 20 moderate smokers and 20 non-smokers with severe periodontitis were examined after initial diagnosis, and non-surgical active and supportive therapies for 1-6 years (mean follow-up = 3.37 years)...

Since the beginning of the COVID-19 pandemic, healthcare providers worldwide have faced many obstacles in the diagnostic evaluation of patients for severe acute respiratory syndrome coronavirus 2, the causative virus. Even with the application of statistical inference by Bayes' theorem to estimate the probability of a diagnosis, with and without testing capabilities, some cases may still carry a degree of uncertainty. This has important implications for limiting the spread of disease. The basis for isolation and quarantine is a known diagnosis...

OBJECTIVE: Algorithms have been developed to identify ovarian cancer in women with a pelvic mass. The aim of this study was to determine how the base rates of ovarian cancer influence the case finding abilities of recently developed algorithms applicable to pelvic tumors. We used three ovarian cancer algorithms and the principle of Bayes' theorem for risk estimation. METHODS: First, we evaluated the case finding abilities of the Risk of Malignancy Algorithm, the Rajavithi-Ovarian Predictive Score, and the Copenhagen Index in a prospectively collected sample at Oslo University Hospital of 227 postmenopausal women with a 74% base rate of ovarian cancer...

BACKGROUND: Following Bayes theorem, ventriculomegaly and ataxia confer only a 30% chance of idiopathic Normal Pressure Hydrocephalus (NPH). When coupled with positive responses to best diagnostic testing (extended lumbar drainage), 70% of patients recommended for shunting will not actually have NPH. This is inadequate clinical care. OBJECTIVE: To determine the proportion of alternative and treatable diagnoses in patients referred to a multidisciplinary NPH clinic...

BACKGROUND: Peanut allergy (PA) is associated with an economic and psychological burden on patients and families. Its diagnosis includes tests for peanut specific immunoglobulin E (sIgE), the values of which usually are categorized as positive or negative using a predefined cutoff (usually 0.35 kU/L). With the use of Bayes' theorem, this categorization can be replaced with a continuous interpretation of sIgE, which accounts for the prevalence of PA and history of ingestion. OBJECTIVE: To evaluate a method for estimating the likelihood ratio (LR) for each value of sIgE by performing a pilot investigation with the results of oral food challenges...

Purpose: Pulmonary tuberculosis (PTB) is one of the major health problems in the elderly population, causing significant morbidity and mortality. The aim of this study is to evaluate the significance of the high-resolution computed tomography (HRCT) modality for the diagnosis of PTB, in comparison to culture test. Material and methods: Thoracic HRCT images of the study population, comprising 124 patients clinically suspected for PTB with smear and culture reports, were analysed for sensitivity and specificity of the HRCT test...

This paper is a collection of telemedicine techniques used by wireless body area networks (WBANs) for emergency conditions. Furthermore, Bayes' theorem is proposed for predicting emergency conditions. With prior knowledge, the posterior probability can be found along with the observed evidence. The probability of sending emergency messages can be determined using Bayes' theorem with the likelihood evidence. It can be viewed as medical decision-making, since diagnosis conditions such as emergency monitoring, delay-sensitive monitoring, and general monitoring are analyzed with its network characteristics, including data rate, cost, packet loss rate, latency, and jitter...