Modelling variation in test sensitivity for monitoring leptospirosis in beef cattle.

When Bayesian latent class analysis is used for diagnostic test data in the absence of a gold standard test, it is common to assume that any unknown test sensitivities and specificities are constant across different populations. Indeed this assumption is often necessary for model identifiability. However there are a number of practical situations, depending on the type of test and the nature of the disease, where this assumption may not be true. We present a case study of using a microscopic agglutination test to diagnose leptospiroris infection in beef cattle, which strongly suggests that sensitivity in particular varies among herds. We develop and fit an alternative model in which sensitivity is related to within-herd prevalence, and discuss the statistical and epidemiological implications.

Patterns of Sexual Activity and the Development of Sexual Pain Across the Menopausal Transition.

OBJECTIVE: To examine whether patterns of sexual intercourse frequency and demographic, menopausal status, genitourinary, health, and psychosocial factors are associated with developing sexual pain across the menopausal transition. METHODS: These were longitudinal analyses of questionnaire data from the multicenter, multiracial and ethnic prospective cohort SWAN (Study of Women's Health Across the Nation) (1995-2008). We used multivariable discrete-time proportional hazards models to examine whether incident sexual pain was associated with preceding long-term (up to 10 visits) or short-term (two and three visits) sexual intercourse frequency patterns or other factors (eg, menopause status, genitourinary symptoms, lifestyle factors, and mental health). RESULTS: Of the 2,247 women with no sexual pain at baseline, 1,087 (48.4%) developed sexual pain at least "sometimes" up to 10 follow-up visits over 13 years. We found no consistent association between prior patterns of sexual intercourse frequency and development of sexual pain. For example, neither decreases in intercourse frequency from baseline (adjusted hazard ratio [aHR] 0.93, 95% CI 0.73-1.19) nor decreases in frequency over three prior visits (aHR 1.00, 95% CI 0.72-1.41) were associated with incident pain. Reasons for interruptions in intercourse activity at the prior visit, including lack of interest (aHR 1.64, 95% CI 0.74-3.65) and relationship issues (aHR 0.36, 95% CI 0.04-2.88), were not associated with developing pain. Being postmenopausal using hormone therapy (aHR 3.16, 95% CI 1.46-6.85), and reported vaginal dryness (aHR 3.73, 95% CI 2.88-4.83) were most strongly associated with incident sexual pain. CONCLUSION: Long-term and short-term declines in sexual intercourse frequency across the menopausal transition were not associated with increased hazard of developing pain with intercourse. This empirical evidence does not support the common belief that a reduction in women's sexual frequency is responsible for their symptoms of sexual pain.

Analysis of German BSE Surveillance Data: Estimation of the Prevalence of Confirmed Cases versus the Number of Infected, but Non-Detected, Cattle to Assess Confidence in Freedom from Infection.

Quantitative risk assessments for Bovine spongiform encephalopathy (BSE) necessitate estimates for key parameters such as the prevalence of infection, the probability of absence of infection in defined birth cohorts, and the numbers of BSE-infected, but non-detected cattle entering the food chain. We estimated three key parameters with adjustment for misclassification using the German BSE surveillance data using a Gompertz model for latent (i.e., unobserved) age-dependent detection probabilities and a Poisson response model for the number of BSE cases for birth cohorts 1999 to 2015. The models were combined in a Bayesian framework. We estimated the median true BSE prevalence between 3.74 and 0.216 cases per 100,000 animals for the birth cohorts 1990 to 2001 and observed a peak for the 1996 birth cohort with a point estimate of 16.41 cases per 100,000 cattle. For birth cohorts ranging from 2002 to 2013, the estimated median prevalence was below one case per 100,000 heads. The calculated confidence in freedom from disease (design prevalence 1 in 100,000) was above 99.5% for the birth cohorts 2002 to 2006. In conclusion, BSE surveillance in the healthy slaughtered cattle chain was extremely sensitive at the time, when BSE repeatedly occurred in Germany (2000-2009), because the entry of BSE-infected cattle into the food chain could virtually be prevented by the extensive surveillance program during these years and until 2015 (estimated non-detected cases/100.000 [95% credible interval] in 2000, 2009, and 2015 are 0.64 [0.5,0.8], 0.05 [0.01,0.14], and 0.19 [0.05,0.61], respectively).

Comparative in vitro biomechanical evaluation of two soft tissue defect products.

A soft tissue defect is often an unavoidable consequence of various surgical procedures or a result of trauma. Recently, intraoperative use of xenograft as a patch to the soft tissue defect has become popular with various products available in the market. In this study, mechanical properties of the OrthADAPT™ Bioimplants (Pegasus Biologics, Irvine, CA), new xenograft products composed of collagen from equine pericardium, were evaluated individually and against an existing bioimplant product. The OrthADAPT™ Bioimplants have three subtypes which differ in the degree of crosslinking of collagen strands. The three products are named as FX, PX, and MX in the order of the degree of collagen crosslinking and likely durability in vivo, with FX most dense in crosslinking and hence most durable. The three subtypes underwent three destructive mechanical tests: tensile strength, suture pull-out strength, and burst strength test. In tensile strength and suture pull-out strength tests, the three products were compared with CuffPatch™, a similar collagen-based xenograft product from a competing manufacturer. In the burst strength test, the three products were compared with untreated equine pericardium tissue. In tensile strength and suture pull-out strength tests, the products FX and MX were shown to have mechanical properties that were comparable with CuffPatch, while the mechanical strength of PX was significantly inferior to FX and CuffPatch in tensile strength test. In burst strength test, there were no differences in mechanical properties among the three OrthADAPT Bioimplants. This study demonstrates the biomechanical equivalence of OrthADAPT with CuffPatch. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2007.

Communication Skills of Grandview/Southview Medical Center General Surgery Residents.

CONTEXT: In the transition of osteopathic programs to the single-accreditation graduate medical education (GME) system, residents are required to demonstrate skill in a set of core competencies identified by the Accreditation Council of Graduate Medical Education (ACGME) prior to graduation. Included in those core competencies are interpersonal and communication skills along with professionalism. OBJECTIVES: To assess strengths and weaknesses of residents' interpersonal communication skills and professionalism in the Grandview/Southview Medical Center (Dayton, OH) osteopathic general surgery program using the validated Communication Assessment Tool (CAT). METHODS: From November 2014 to June 2018, all patients who presented for an appointment at the Cassano General Surgery Clinic were asked by a medical assistant to complete a CAT questionnaire following their encounter with a resident physician. Patients at Cassano, an outpatient office-based facility directed to the underserved local community, are seen first by an intern, then by a 4th or 5th year resident and later by an attending physician. Patients 18 years of age or older were included; patients were excluded if they were unable to understand or read English. Patient demographics were collected, including age, gender, race/ethnicity, and previous exposure to this resident physician. Each resident's name was replaced on the CAT with a number for data analysis. The resident variables collected for this study included year of training, gender, and native language. RESULTS: The mean response for all CAT items was 4.5 out of 5, indicating that responses to resident performance were largely positive. Patients responded to 4 of the 14 CAT items with only excellent, very good, or good responses and no fair or poor responses. Four items had only 1 fair or poor response. The remaining 6 items received more than 1 fair or poor response: "greeted me in a way that made me feel comfortable" (#1), "talked in terms I could understand" (#8), "encouraged me to ask questions" (#10), "involved me in decisions as much as I wanted" (#11), "showed care and concern" (#13), and "spent the right amount of time with me" (#14). CONCLUSIONS: Attending surgeons evaluate residents in multiple areas from a doctor's perspective, but there is a potential lack of correlation between that evaluation and a patient's experience, which is paramount in osteopathic medicine. Patient responses to the CAT questionnaire can be used by program directors to identify deficiencies in milestone/competency achievement and facilitate improvement both individually and programmatically for residents according to ACGME standards.

F2-isoprostanes in Fish mucus: A new, non-invasive method for analyzing a biomarker of oxidative stress.

F2-isoprostanes (F2-isoPs) are a reliable biomarker class for oxidative stress in vivo in animals. These compounds are traditionally measured in matrices like liver and plasma, however social and environmental pressures warrant the development of non-lethal and non-invasive methods to assess animal health. Therefore, this study aimed to develop a high-performance liquid chromatography tandem mass spectrometry (HPLC-ESI-MS/MS) method to separate and detect F2-isoPs in fish mucus. The method was developed and validated for four native F2-isoP isomers using Northern pike mucus (Esox lucius). Linearity was observed between 5 and 1000 pg/µL. The limits of detection of the four F2-IsoP isomers ranged from 0.63 to 2.0 ng/g. Recoveries ranged from 78 to 95%, and matrix effects were small (<10%). The between-day and within-day repeatability for all target analytes was lower than 20% RSD. Endogenous F2-isoPs were measured in the pike mucus (5.3-28.8 ng/g). A preliminary study of baseline F2-isoP concentrations in lake trout (Salvelinus namaycush) captured from five lakes at the IISD-Experimental Lakes Area in Northwestern Ontario, Canada, was also conducted to test the interspecies applicability of the method. Endogenous F2-isoPs were quantified in lake trout (6.3-132 ng/g). Lake trout samples displayed large variability within and between the different lakes, which suggests sampling methods may require adjustment for this species. This work developed a sensitive analytical method for measuring F2-isoPs in fish mucus, however several further studies are required to determine its ability to accurately measure oxidative stress in fish species.

Gold standards are out and Bayes is in: Implementing the cure for imperfect reference tests in diagnostic accuracy studies.

Bayesian mixture models, often termed latent class models, allow users to estimate the diagnostic accuracy of tests and true prevalence in one or more populations when the positive and/or negative reference standards are imperfect. Moreover, they allow the data analyst to show the superiority of a novel test over an old test, even if this old test is the (imperfect) reference standard. We use published data on Toxoplasmosis in pigs to explore the effects of numbers of tests, numbers of populations, and dependence structure among tests to ensure model (local) identifiability. We discuss and make recommendations about use of priors, sensitivity analysis, model identifiability and study design options, and strongly argue for the use of Bayesian mixture models as a logical and coherent approach for estimating the diagnostic accuracy of two or more tests.

Comparing Objective and Subjective Bayes Factors for the Two-Sample Comparison: The Classification Theorem in Action.

Many Bayes factors have been proposed for comparing population means in two-sample (independent samples) studies. Recently, Wang and Liu (2015) presented an "objective" Bayes factor (BF) as an alternative to a "subjective" one presented by Gönen et al. (2005). Their report was evidently intended to show the superiority of their BF based on "undesirable behavior" of the latter. A wonderful aspect of Bayesian models is that they provide an opportunity to "lay all cards on the table." What distinguishes the various BFs in the two-sample problem is the choice of priors (cards) for the model parameters. This article discusses desiderata of BFs that have been proposed, and proposes a new criterion to compare BFs, no matter whether subjectively or objectively determined: A BF may be preferred if it correctly classifies the data as coming from the correct model most often. The criterion is based on a famous result in classification theory to minimize the total probability of misclassification. This criterion is objective, easily verified by simulation, shows clearly the effects (positive or negative) of assuming particular priors, provides new insights into the appropriateness of BFs in general, and provides a new answer to the question, "Which BF is best?"

Patterns of Cardiometabolic Health as Midlife Women Transition to Menopause: A Prospective Multiethnic Study.

CONTEXT: Cardiometabolic conditions increase in midlife, but early customized prevention strategies are not established for such women. OBJECTIVE: To characterize and identify factors longitudinally related to constellations of cardiometabolic risk components in multiracial/ethnic women in midlife. DESIGN: We conducted a prospective, longitudinal, multiethnic cohort study of 3003 midlife women undergoing menopausal transition (MT). Metabolic syndrome (MetS) was defined as having at least three of five components: high fasting triglyceride (hTG) level, low high-density lipoprotein cholesterol (lHDL-C) level, high fasting plasma glucose (hGluc) level, large waist circumference (abdominal obesity; Ob), and hypertension (HTN). We described the patterns of constellations and estimated hazard ratios (HRs) for constellations at (i) incident MetS and (ii) recovery from MetS, using multivariable-adjusted Cox regression. SETTING: Seven US sites. PARTICIPANTS: In all, 1412 non-Hispanic white, 851 black, 272 Japanese, 237 Hispanic, and 231 Chinese women. EXPOSURES: Race/ethnicity, lifestyle factors, and MT stage. MAIN OUTCOMES MEASURES: Cardiometabolic constellations, incident MetS, and MetS recovery. RESULTS: Central obesity was the most frequent component. Having no components was the most frequent (31%) baseline constellation. Physical activity (HR = 1.68; 95% CI: 1.06, 2.68) and lower caloric intake (HR = 0.96; 95% CI: 0.93, 0.99 per 100 cal/d) were associated with recovery from MetS. Ob/hTG/lHDL-C (18%), Ob/HTN/lHDL-C (16%), and Ob/HTN/hGluc (14%) were frequent incident constellations. Physically active women had 26% to 62% lower hazards of incident MetS than inactive women. CONCLUSIONS: Modifiable lifestyle behaviors were related to recovery from MetS and decreased risk of the most frequent MetS constellations in midlife women.

Identification of halogenated polycyclic aromatic hydrocarbons in biological samples from Alberta Oil-Sands Region.

Halogenated polycyclic aromatic hydrocarbons (HPAHs) were identified in biological samples from the Alberta Oil-Sands Region (AOSR) using gas chromatography coupled with high-resolution time-of-flight mass spectrometry (GC-HRTOF-MS) at a resolving power of 25,000. Knowledge of the electron ionization (EI) fragmentation behavior of individual HPAH isomers, achieved by injecting authentic standards in full-scan MS mode, was paramount in identifying a suite of HPAHs in samples from the AOSR. Confirmation of compounds in biological samples was based on the measured mass accuracy (±3 ppm) of 2 characteristic ions prominent in the EI mass spectra of each compound. Numerous compounds were detected in the high resolution total ion chromatogram in liver extracts of 4 biological species from the AOSR: river otter (Lontra Canadensis), northern pike (Esox lucius), lake whitefish (Coregonus clupeaformis) and snails (Gastropod sp.) many of which remain unidentified. Careful examination of the high-resolution accurate mass data suggests that dichloro-anthracene/phenanthrene, bromo-anthracene/phenanthrene and dibromo-fluorene were present in the biological samples. Lipid corrected concentrations of dichloro-PAHs were estimated to be 16.3 ±â€¯11.4 (n = 4) and 5.5 (n = 1) ng/g in lake whitefish and river otter, respectively. Concentrations of mono-bromo-PAHs were an order of magnitude greater in snails (170.5 ng/g) than in northern pike (12.5 ng/g) while concentrations of dibromo-PAHs were 4 times greater in snails than in northern pike. The detection of these compounds in biota implies that these compounds are bioaccumulative. The liver-based biomagnification factor of the dichloro-PAH congener in the river otter/lake whitefish feeding relationship is much smaller than 1 implying that this compound does not biomagnify.

Comprehensive two-dimensional gas chromatography high-resolution mass spectrometry for the analysis of substituted and unsubstituted polycyclic aromatic compounds in environmental samples.

Polycyclic aromatic compounds (PACs) consists of multiple compounds and the number of theoretically possible isomers can reach into the thousands. Currently each PAC group is quantified collectively as a single group of compounds. However, individual PACs can reveal important information on how the PACs were formed and this information may be used to determine sources of PACs in environmental samples, It is hypothesized that many of the limitations with characterizing alkylated PACs with one dimensional gas-chromatography (1D GC) can be circumvented using GC × GC (two dimensional gas chromatography). Here we apply comprehensive GCxGC coupled to high-resolution time of flight mass spectrometry (GC × GC-HFTOF-MS) to aid in the separation, identification and quantitation of APACs in three environmental matrices: mussel tissue (Mytilus edulis), lubricating oil and coal. In the absence of authentic analytical standards, differences in the mass spectral fragmentation pattern of isomers were used to confirm the identity of isomers within a PAC group. The method was validated according to the EURACHEM guidelines and used to quantify a biological standard reference material (SRM 2974a). The method met all the standard method performance requirements such as trueness, precision and measurement of uncertainty and is fit for quantifying these compounds in biota. Furthermore, the method was used to identify and quantify additional PAC compounds in the SRM 2974a material which to date have not been certified. With appropriate statistical analytical tools, the described GC × GC method can be used as a tool for more robust source fingerprinting and source apportionment of PACs in the environment.

Absorption of polycyclic aromatic hydrocarbons by a highly absorptive polymeric medium.

The efficacy of a lightly cross-linked polymeric bead to absorb polycyclic aromatic hydrocarbons (PAHs) from the surface of fresh- and salt-water in a simulated oil-spill scenario was assessed in this study. A layer of PAHs at the water surface was created by first preparing the PAHs in hexane and then carefully spiking this mixture onto the surface of water. Beads were then applied to the surface of the organic phase and the amount of hydrocarbons absorbed by the beads was examined at prescribed time intervals and at different temperatures. Absorption of PAHs into the beads was exhaustive with ∼86 ±â€¯4% being selectively removed from the organic phase by 120 s. First order reaction rates best described the uptake kinetics and absorption rates ranged from 0.0085 (naphthalene) to 0.0325 s-1 (dibenzo[a,h]anthracene). Absorption of PAHs into the beads was driven by molecular volume (A3). Uptake rates increased markedly for PAHs with molecular volumes between 130 A3 and 190 A3. Beyond this molecular volume there was no apparent change in the rate of uptake. This study shows that these polymeric beads have a high affinity for PAHs and can be used under various environmental conditions with negligible difference in absorptive efficacy.

Enumeration of the constitutional isomers of environmentally relevant substituted polycyclic aromatic compounds.

Polycyclic aromatic compounds (PACs) are a diverse group of environmentally relevant compounds which can be persistent, bioaccumulative and toxic. The cyclic backbone of PACs can be substituted with halogens or hydrocarbon chains. The amount and positions of these substituents influence their toxicity. For many classes of PACs, substitution creates mixtures containing large numbers of isomers. For example, 209 theoretical isomers of chlorinated biphenyls are possible. Many other classes of environmentally relevant PACs exist where the number of theoretical isomers are unknown. Here, a mathematical approach using molecular symmetry and the binomial coefficient is presented that determines the number of theoretical isomers of PACs. The approach was validated on PACs with known isomer numbers and then applied to PACs with unknown isomer numbers. When the approach was applied to alkylated polycyclic aromatic hydrocarbons, the possible theoretical isomers ranged from 2 for C1 naphthalene up to 19 502 for C6 dibenzo(ah)anthracene. Heterocyclic PACs had similar numbers ranging from 4 isomers for C1 dibenzothiophene to 13 938 for C6 dibenzo[a,i]carbazole. The work presented will aide analytical chemists and ecotoxicologists in their efforts to develop methods to measure these compounds, and in attempting to assess the toxicity and environmental fate of individual isomers.

Factors associated with reasons incontinent midlife women report for not seeking urinary incontinence treatment over 9 years across the menopausal transition.

OBJECTIVE: We explored factors associated with reasons that women with urinary incontinence (UI) reported for not seeking treatment for their UI from a healthcare professional and whether reasons differed by race/ethnicity, socioeconomic status, or education. METHODS: We analyzed questionnaire data collected from 1995 to 2005 in the Study of Women's Health Across the Nation. In visits 7 to 9, we elicited reasons that women with UI reported for not seeking treatment and condensed them into: UI not bad enough, beliefs about UI causes (UI is a normal consequence of aging or childbirth), and motivational barriers (such as feeling too embarrassed). We used Generalized Estimating Equations and ordinal logistic regression to evaluate factors associated with these reported reasons and number of reasons. RESULTS: Of the 1,339 women reporting UI, 814 (61.0%) reported they did not seek treatment for UI. The most frequently reported reasons were as follows: "UI not bad enough" (73%), "UI is a normal part of aging" (53%), and "healthcare provider never asked" (55%). Women reporting daily UI had higher odds of reporting beliefs about UI causes (adjusted odds ratio UI 3.16, 95% CI 1.64-6.11) or motivational barriers (adjusted odds ratio UI 2.36, 95% CI 1.21-4.63) compared with women reporting less than monthly UI. We found no interactions by race/ethnicity, socioeconomic status, or education and UI characteristics in reasons that women reported for not seeking UI treatment. CONCLUSIONS: Over half of women who did not seek treatment for their UI reported reasons that could be addressed by public health and clinical efforts to make UI a discussion point during midlife well-women visits.

Validation of a simultaneous method for determining polycyclic aromatic compounds and alkylated isomers in biota.

RATIONALE: There is a need for a validated method to improve detection limits and simultaneously quantify polycyclic aromatic compounds (PACs, both parent and alkylated homologues) in biota by gas chromatography/tandem mass spectrometry because of their environmental significance. The validation of the method was performed in accordance to the Eurachem Guide to Quality in Analytical Chemistry. METHODS: Gas chromatography coupled with a triple quadrupole mass spectrometer used in multiple reaction monitoring (MRM) mode was used for detection and quantification. Retention time windows and selective MRM ion transitions were optimized for a suite of PACs. The developed method was validated by comparing our measurements made on a reference material of freeze-dried mussel tissue (Mytilus edulis) with the certified values. RESULTS: Linearity was observed between 10-1000 pg/µL (PAHs) and 2-500 pg/µL (alkyl-PACs including S-based PACs). The overall mean (±SD) for the limits of detection of 43 PACs studied were 0.305 ± 0.276 and 2.69 ± 1.10 ng/g, respectively. For the 14 certified target analytes, the percent relative error ranged from 1.3 to 33%. With the exception of benzo(a)pyrene, the between-day and within-day repeatability for all target analytes was lower than 15% RSD. CONCLUSIONS: This is the first report of a fully validated method to simultaneously quantify PACs in biota performed in an ISO accredited laboratory.

Live attenuated influenza virus vaccine reduces virus shedding of newborn piglets in the presence of maternal antibody.

BACKGROUND: Influenza A virus in swine (IAV-S) causes an acute respiratory disease of swine which results in great economic losses in pig production. Major control strategies include the use of killed vaccines (KV) in breeding females to confer passive immunity to their offspring. A bivalent H1N1 and H3N2 NS1-truncated live attenuated IAV-S vaccine have recently become available, which showed promising results in young pigs. OBJECTIVE: The aim of this study was to investigate the effect of an intranasal vaccination of newborn pigs with or without maternally derived antibodies (MDA) on virus shedding (via nasal swabs tested by virus isolation). METHODS: The study was performed as intratracheal challenge experiments with either a heterologous H1N2 or H3N2 viruses. RESULTS AND CONCLUSION: The results of this study showed a significant decrease in the incidence and duration of shedding viable virus for vaccinated newborn piglets with or without MDA, providing strong evidence that intranasal vaccination is overcoming passively acquired maternal immunity. This study indicates that intranasal vaccination with a truncated NS1 live attenuated IAV-S vaccine of newborn piglets with maternal antibodies can be a valuable tool for reducing the prevalence of heterologous H1N2 and H3N2 IAV-S in pig herds.

A Flexure-Guided Piezo Drill for Penetrating the Zona Pellucida of Mammalian Oocytes.

Mammalian oocytes such as mouse oocytes have a highly elastic outer membrane, zona pellucida (ZP) that cannot be penetrated without significantly deforming the oocyte, even with a sharp micropipette. Piezo drill devices leverage lateral and axial vibration of the micropipette to accomplish ZP penetration with greatly reduced oocyte deformation. However, existing piezo drills all rely on a large lateral micropipette vibration amplitude ( 20 ) and a small axial vibration amplitude (0.1 ). The very large lateral vibration amplitude has been deemed to be necessary for ZP penetration although it also induces larger oocyte deformation and more oocyte damage. This paper reports on a new piezo drill device that uses a flexure guidance mechanism and a systematically designed pulse train with an appropriate base frequency. Both simulation and experimental results demonstrate that a small lateral vibration amplitude (e.g., 2 ) and an axial vibration amplitude as large as 1.2 were achieved. Besides achieving 100% effectiveness in the penetration of mouse oocytes (n = 45), the new piezo device during ZP penetration induced a small oocyte deformation of 3.4 versus larger than 10 using existing piezo drill devices.

STARD-BLCM: Standards for the Reporting of Diagnostic accuracy studies that use Bayesian Latent Class Models.

The Standards for the Reporting of Diagnostic Accuracy (STARD) statement, which was recently updated to the STARD2015 statement, was developed to encourage complete and transparent reporting of test accuracy studies. Although STARD principles apply broadly, the checklist is limited to studies designed to evaluate the accuracy of tests when the disease status is determined from a perfect reference procedure or an imperfect one with known measures of test accuracy. However, a reference standard does not always exist, especially in the case of infectious diseases with a long latent period. In such cases, a valid alternative to classical test evaluation involves the use of latent class models that do not require a priori knowledge of disease status. Latent class models have been successfully implemented in a Bayesian framework for over 20 years. The objective of this work was to identify the STARD items that require modification and develop a modified version of STARD for studies that use Bayesian latent class analysis to estimate diagnostic test accuracy in the absence of a reference standard. Examples and elaborations for each of the modified items are provided. The new guidelines, termed STARD-BLCM (Standards for Reporting of Diagnostic accuracy studies that use Bayesian Latent Class Models), will facilitate improved quality of reporting on the design, conduct and results of diagnostic accuracy studies that use Bayesian latent class models.