Improving the Verification of Timed Systems Using Influence Information

Abstract. The parallel composition with observers is a well-known approach to check or test properties over formal models of concurrent and real-time systems. We present a newtechnique to reduce the size of the resulting model. Our approach has been developed for a formalism based on Timed Automata. Firstly, it discovers relevant components and clocks at each location of the observer using influence information. Secondly, it outcomes an abstraction which is equivalent to the original model up to branching-time structure and can be treated by verification tools such as Kronos [12] or OpenKronos [23]. Our experiments suggest that the approach may lead to significant time and space savings during verification phase due to state space reduction and the existence of shorter counterexamples in the optimized model.

Mobile Application to Identify Cancer Treatment–Related Financial Assistance: Results of a Randomized Controlled Trial

PURPOSE: Insured patients with cancer face high treatment-related, out-of-pocket (OOP) costs and often cannot access financial assistance. We conducted a randomized, controlled trial of Bridge, a patient-facing app designed to identify eligible financial resources for patients. We hypothesized that patients using Bridge would experience greater OOP cost reduction than controls. METHODS: We enrolled patients with cancer who had OOP expenses from January 2018 to March 2019. We randomly assigned patients 1:1 to intervention (Bridge) versus control (financial assistance educational websites). Primary and secondary outcomes were self-reported OOP costs and subjective financial distress 3 months postenrollment. In post hoc analyses, we analyzed application for and receipt of financial assistance at 3 months postenrollment. We used chi-square, Mann-Whitney tests, and logistic regression to compare study arms. RESULTS: We enrolled 200 patients. The median age was 57 years (IQR, 47.0-63.0). Most patients had private insurance (71%), and the median household income was $62,000 in US dollars (USD) (IQR,$36,000-$100,000 [USD]). Substantial missing data precluded assessment of primary and secondary outcomes. In post hoc analyses, patients in the Bridge arm were more likely than controls to both apply for and receive financial assistance. CONCLUSION: We were unable to test our primary outcome because of excessive missing follow-up survey data. In exploratory post hoc analyses, patients who received a financial assistance app were more likely to apply for and receive financial assistance. Ultimately, our study highlights challenges faced in identifying measurable outcomes and retaining participants in a randomized, controlled trial of a mobile app to alleviate financial toxicity. </jats:sec

Barriers to health care services for migrants living with HIV in Spain

Background In Spain, migrants are disproportionately affected by HIV and experience high rates of late diagnosis. We investigated barriers to health care access among migrants living with HIV (MLWH) in Spain. Methods Cross sectional electronic survey of 765 adult HIV-positive migrants recruited within 18 health care settings between July 2013 and July 2015. We collected epidemiological, demographic, behavioral and clinical data. We estimated the prevalence and risk factors of self-reported barriers to health care using multivariable logistic regression. Results Of those surveyed, 672 (88%) had information on health care access barriers: 23% were women, 63% from Latin America and Caribbean, 14% from Sub-Saharan Africa and 15% had an irregular immigration status. Men were more likely to report barriers than women (24% vs. 14%, P = 0.009). The main barriers were: lengthy waiting times for an appointment (9%) or in the clinic (7%) and lack of a health card (7%). Having an irregular immigration status was a risk factor for experiencing barriers for both men (OR: (4.0 [95%CI: 2.2-7.2]) and women (OR: 10.5 [95%CI: 3.1-34.8]). Men who experienced racial stigma (OR: 3.1 [95%CI: 1.9-5.1]) or food insecurity (OR: 2.1 [95%CI: 1.2-3.4]) were more likely to report barriers. Women who delayed treatment due to medication costs (6.3 [95%CI: 1.3-30.8]) or had a university degree (OR: 5.8 [95%CI: 1.3-25.1]) were more likely to report barriers. Conclusion Health care barriers were present in one in five5 MLWH, were more common in men and were associated to legal entitlement to access care, perceived stigma and financial constraints