Extending Hui-Walter framework to correlated outcomes with application to diagnosis tests of an eye disease among premature infants.

Diagnostic accuracy, a measure of diagnostic tests for correctly identifying patients with or without a target disease, plays an important role in evidence-based medicine. Diagnostic accuracy of a new test ideally should be evaluated by comparing to a gold standard; however, in many medical applications it may be invasive, costly, or even unethical to obtain a gold standard for particular diseases. When the accuracy of a new candidate test under evaluation is assessed by comparison to an imperfect reference test, bias is expected to occur and result in either overestimates or underestimates of its true accuracy. In addition, diagnostic test studies often involve repeated measurements of the same patient, such as the paired eyes or multiple teeth, and generally lead to correlated and clustered data. Using the conventional statistical methods to estimate diagnostic accuracy can be biased by ignoring the within-cluster correlations. Despite numerous statistical approaches have been proposed to tackle this problem, the methodology to deal with correlated and clustered data in the absence of a gold standard is limited. In this article, we propose a method based on the composite likelihood function to derive simple and intuitive closed-form solutions for estimates of diagnostic accuracy, in terms of sensitivity and specificity. Through simulation studies, we illustrate the relative advantages of the proposed method over the existing methods that simply treat an imperfect reference test as a gold standard in correlated and clustered data. Compared with the existing methods, the proposed method can reduce not only substantial bias, but also the computational burden. Moreover, to demonstrate the utility of this approach, we apply the proposed method to the study of National-Eye-Institute-funded Telemedicine Approaches to Evaluating of Acute-Phase Retinopathy of Prematurity (e-ROP), for estimating accuracies of both the ophthalmologist examination and the image evaluation.

Preliminary Screening Questionnaire for Sjögren's Syndrome in the Rheumatology Setting.

OBJECTIVE: Sjögren's syndrome (SS) is frequently undetected or misdiagnosed as other rheumatologic diseases. We aimed to develop an SS screening questionnaire for the rheumatology practice. METHODS: We developed the Sjögren's Syndrome Screening Questionnaire (SSSQ) via secondary analysis of data from 974 participants referred by rheumatologists to the Sjögren's International Collaborative Clinical Alliance (SICCA) study. Participants answered 88 questions regarding symptoms, medical history, and demographics. They underwent ocular, dental, and serologic tests and were classified as SS or non-SS using the 2016 American College of Rheumatology/European League Against Rheumatism classification criteria. We conducted univariate and multivariate logistic regression to identify questions most discriminative of SS, from which we derived an individual's likelihood of SS ("SSSQ score"). RESULTS: Five questions were significantly discriminative of SS in the multivariate analysis (p < 0.05): (1) Can you eat a cracker without drinking a fluid/liquid? (no: odds ratio [OR], 1.39; 95% confidence interval [CI], 1.06-1.82]); (2) How would you describe your dental and oral health in general? (fair/poor: OR, 1.68; 95% CI, 1.04-2.75); (3) During the last week, have you experienced tearing? (none of the time: OR, 2.26; 95% CI, 1.23-4.34); (4) Are you able to produce tears? (no: OR, 1.62; 95% CI, 1.12-2.37); and (5) Do you currently smoke cigarettes? (no: OR, 2.83; 95% CI, 1.69-4.91). SSSQ score ≥7 (possible range, 0-11) distinguishes SS from non-SS patients with 64% sensitivity and 58% specificity (area under receiver operating characteristic curve, 0.65). CONCLUSIONS: The SSSQ is a simple 5-item questionnaire designed to screen for SS in clinical practice, with a potential impact to reduce delays in diagnosis.

A New Screening Questionnaire to Identify Patients With Dry Eye With a High Likelihood of Having Sjögren Syndrome.

PURPOSE: To develop a screening questionnaire to identify patients with dry eye with a high likelihood of having underlying Sjögren syndrome (SS). METHODS: This was a cross-sectional study of participants with dry eye complaints who were self-referred or referred by an ophthalmologist to the Sjögren's International Collaborative Clinical Alliance study. Symptoms and ocular surface examination findings were candidate predictors. Univariable and multivariable logistic regression analyses were performed to estimate odds ratios (ORs) and 95% confidence intervals (95% CI) for the association of a symptom and/or ocular sign with SS. Area under the receiver operating characteristic curve (AUC) was used to summarize the predictive ability of different regression models and the derived likelihood score. RESULTS: Four questions were statistically significant in the final multivariable model: 1) Is your mouth dry when eating a meal? [Yes = OR 1.63 (1.18-2.26)]; 2) Can you eat a cracker without drinking a fluid or liquid? [No = OR 1.46 (1.06-2.01)]; 3) How often do you have excessive tearing? [None of the time = OR 4.06 (1.81-9.10)]; and 4) Are you able to produce tears? [No = OR 2.24 (1.62-3.09)]. The SS likelihood score had an AUC of 0.70 (95% CI, 0.66-0.73), and when including tear break-up time and conjunctival staining, it yielded an AUC of 0.79 (95% CI, 0.77-0.82). CONCLUSIONS: This questionnaire can be used to identify patients with dry eye with a high likelihood of having SS. With future refinement and validation, this screening tool could be used alone or in combination with examination findings to identify patients with SS earlier, thereby facilitating better clinical outcomes.

Ameloblastoma: 25 Year Experience at a Single Institution.

Ameloblastoma is a rare, locally aggressive odontogenic neoplasm, accounting for fewer than 1 % of head and neck tumors. Recent literature suggests that the initial surgical approach and histologic growth patterns are the most important prognostic determinants in ameloblastoma. The aim of this study was to compare the clinical presentation, management, and outcomes of patients with ameloblastoma with data reported in the literature; the study spanned 2 decades at a single institution. The institution's database was searched for all patients with pathologically confirmed ameloblastoma, diagnosed between 1990 and 2015. The data collected included sex, age, clinical and imaging findings, management, histologic pattern, clearance of surgical margins, length of follow-up, time to recurrence, and disease-related mortality. The potential risk factors of recurrence were evaluated using log-rank test, proportional hazard model, and Fisher exact test. Review of the database yielded 54 patients with pathologically confirmed ameloblastoma and follow-up. Recurrence was noted in 13 (24 %) patients. Surgical approach was associated with the risk of recurrence (6.1 % following radical resection vs. 52 % following limited surgery, p = 0.002). There were trends toward higher recurrence rate in the group with pathologically documented positive margins (p = 0.054) and in follicular ameloblastoma (p = 0.35). Transformation into ameloblastic carcinoma was identified in two patients. There was no disease-related mortality. Our study confirms the recent data regarding the importance of radical surgical resection in management of ameloblastoma. Surgical approach appears to be the strongest predictor of tumor clearance.

Taste function in early stage treated and untreated Parkinson's disease.

Since brain stem regions associated with early Parkinson's disease (PD) pathology encroach upon those involved in taste function, the ability to taste may be compromised in PD. However, studies on this point have been contradictory. We administered well-validated whole-mouth and regional taste tests that incorporated multiple concentrations of sucrose, citric acid, caffeine, and sodium chloride to 29 early stage PD patients and 29 age-, sex-, and race-matched controls. Electrogustometry was also performed on the anterior tongue. The PD cohort was tested both on and off dopamine-related medications in counterbalanced test sessions. While whole-mouth taste identification test scores for all stimuli were, on average, nominally lower for the PD patients than for the controls, a trend in the opposite direction was noted for the intensity ratings at the lower stimulus concentrations for all stimuli except caffeine. Moreover, regional testing found that PD subjects tended to rate the stimuli, relative to the controls, as more intense on the anterior tongue and less intense on the posterior tongue. No significant associations were evident between taste test scores and UPDRS scores, L-DOPA medication equivalency values, or [(99m)Tc]TRODAT-1 SPECT imaging of dopamine transporter uptake within the striatum and associated regions. Our findings suggest that suprathreshold measures of taste function are influenced by PD and that this disease differentially influences taste function on anterior (CN VII) and posterior (CN IX) tongue regions. Conceivably PD-related damage to CN IX releases central inhibition on CN VII at the level of the brainstem, resulting in enhanced taste intensity on the anterior tongue.