Room-temperature ferroelectric nematic liquid crystal showing a large and diverging density.

The ferroelectric nematic phase (NF) is a recently discovered phase of matter in which the orientational order of the conventional nematic liquid crystal state is augmented with polar order. Atomistic simulations suggest that the polar NF phase would be denser than conventional nematics owing to contributions from polar order. Using an oscillating U-tube densitometer, we obtain detailed temperature-dependent density values for a selection of conventional liquid crystals with excellent agreement with earlier reports. Having demonstrated the validity of our method, we then record density as a function of temperature for M5, a novel room-temperature ferroelectric nematic material. We present the first experimental density data for a NF material as well as density data for a nematic that has not previously been reported. We find that the room-temperature NF material shows a large (>1.3 g cm-3) density at all temperatures studied, notably including phases without polar order. An increase in density at phase transitions is observed. The magnitude of the increase for the intermediate-to-ferroelectric nematic (NX-NF) transition is an order of magnitude smaller than the isotropic-nematic (I-N) transition. We then probe potential consequences that may result from an elevated density through measurement of the refractive indices (no and ne). The navg of M5 is compared with 5CB and polar smectic liquid crystals. We observe how the highly polar nature of the system counteracts the effects of an increase in density. With knowledge of experimental density, we are able to derive an approximation that yields the polar order parameter, 〈P1〉, from polarisation measurements. Present results may be typical of ferroelectric nematic materials, potentially guiding material development, and is especially relevant for informing ongoing studies into this emerging class of materials.

A causal roadmap for generating high-quality real-world evidence.

Increasing emphasis on the use of real-world evidence (RWE) to support clinical policy and regulatory decision-making has led to a proliferation of guidance, advice, and frameworks from regulatory agencies, academia, professional societies, and industry. A broad spectrum of studies use real-world data (RWD) to produce RWE, ranging from randomized trials with outcomes assessed using RWD to fully observational studies. Yet, many proposals for generating RWE lack sufficient detail, and many analyses of RWD suffer from implausible assumptions, other methodological flaws, or inappropriate interpretations. The Causal Roadmap is an explicit, itemized, iterative process that guides investigators to prespecify study design and analysis plans; it addresses a wide range of guidance within a single framework. By supporting the transparent evaluation of causal assumptions and facilitating objective comparisons of design and analysis choices based on prespecified criteria, the Roadmap can help investigators to evaluate the quality of evidence that a given study is likely to produce, specify a study to generate high-quality RWE, and communicate effectively with regulatory agencies and other stakeholders. This paper aims to disseminate and extend the Causal Roadmap framework for use by clinical and translational researchers; three companion papers demonstrate applications of the Causal Roadmap for specific use cases.

Unilateral, Sectoral Retinal Metastasis of Small-Cell Lung Cancer Mimicking Viral Retinitis.

PURPOSE: To report a case of unilateral, sectoral retinal metastasis of small-cell lung cancer (SCLC) that mimicked cytomegalovirus (CMV) retinitis. METHOD: Case report. RESULTS: A 48-year-old woman presented with a four-week history of a visual field loss in her right eye. She had a past medical history of extensive-stage SCLC with brain metastasis, stable on maintenance atezolizumab for two years. On initial presentation, she was diagnosed with CMV retinitis. No improvement was observed with 4 weeks of oral valganciclovir. Upon referral for a second opinion, her fundus exam appeared compatible with CMV retinitis, and anterior chamber tap for polymerase chain reaction for viral etiologies was performed followed by intravitreal and intravenous ganciclovir without improvement. She was referred for a third opinion, where diagnostic vitrectomy with vitreous and retinal biopsies were consistent with SCLC metastatic to the retina. The patient underwent enucleation of the right eye for definitive pathologic analysis and subsequently was started on additional systemic chemotherapy. CONCLUSION: Retinal metastases are exceedingly rare, particularly retinal metastasis of SCLC. Retinal metastasis should be considered in patients initially diagnosed with viral retinitis who fail to improve despite antiviral therapy, particularly if they have a known history of malignancy. Furthermore, retinal metastasis of SCLC potentially could be misdiagnosed histopathologically as retinoblastoma if the patient's history is unknown and appropriate immunohistochemical stains are not performed.

Long-Term Follow-Up of Outer Retinal Layers in Patients with Epiretinal Membranes.

PURPOSE: This study aimed to investigate the long-term effect of observed epiretinal membranes on the outer retinal layers and visual acuity. METHODS: It is a retrospective observational study. Subjects with an epiretinal membrane and consecutive optical coherence tomography scans were followed for changes in visual acuity, central macular thickness, ellipsoid zone loss, and outer foveal thickness (OFT). RESULTS: The study consisted of 24 eyes of 22 patients, with a mean follow-up of 5 ± 1.6 years. The mean visual acuity was slightly worse at the last follow-up (0.22 ± 0.36 LogMAR [20/33] vs. 0.27 ± 0.36 LogMAR [20/36], p = 0.05). Ellipsoid zone loss was found in 37.5% of eyes. Vision loss was associated with initial size of ellipsoid disruption (p = 0.048) and age (p = 0.027). A decrease in OFT was associated with an initially larger zone of ellipsoid disruption (p = 0.006) and an initially thicker OFT (p = 0.011). An epiretinal membrane associated with vitreomacular adhesion within 1,000 µm of the foveal center at baseline was associated with ellipsoid zone loss (p = 0.012) but not with a change in visual acuity. CONCLUSIONS: Ellipsoid zone changes were common in this study and tended to enlarge over time. Epiretinal membranes associated with vitreomacular adhesion within 1,000 µm of the foveal center may be a risk factor for ellipsoid zone loss.

"An Unusual Case of Primary Vitreoretinal Lymphoma: A Transformed Lymphoma".

PURPOSE: To report a case of primary vitreoretinal lymphoma (VRL) presenting as diffuse large b-cell lymphoma (DLBCL) 19 years after initial systemic follicular lymphoma. METHOD: A case report. RESULTS: An 81-year-old male patient presented with a 1-month history of floaters and blurry vision in the left eye. He had a history of follicular non-Hodgkin lymphoma treated with systemic chemotherapy in 2002 and prostate cancer treated surgically in 2004. Ophthalmic examination revealed vitritis, retinal whitening, perivascular sheathing, and a vascularized cream-colored retinal mass in the superonasal periphery of the left eye. Diagnostic vitrectomy with retina and vitreous biopsies demonstrated DLBCL. Positron emission tomography/computed tomography confirmed the isolated lesion in the left eye without systemic involvement. Treatment with systemic and intraocular chemotherapy was planned. CONCLUSION: To the best of our knowledge, this is the first reported case of primary VRL of DLBCL transformed from follicular lymphoma. Intravitreal and systemic chemotherapy, including rituximab, should be consideered in the management of patients with transformed VRL.

Bilateral neuroretinits and exudative retinal detachment with multifocal subretinal deposits secondary to Bartonella henselae infection.

PURPOSE: to describe a case of bilateral neuroretinitis with bullous retinal detachment and multiple subretinal lesions, in a 10-year-old immunocompetent girl. OBSERVATIONS: A broad workup for infectious, inflammatory and masquerade etiologies was done for the patient, resulting in positive IgM and IgG for Bartonella henselae. The patient demonstrated improvement in the visual acuity, and rapid resolution of the retinal detachment and subretinal lesions in both eyes in response to systemic rifampin, doxycycline and corticosteroids. CONCLUSIONS AND IMPORTANCE: Bartonella henselae neuroretinitis may present as an acute form of bullous retinal detachment with multiple subretinal lesions and markedly reduced vision. Significant visual improvement may occur with prompt treatment with a combination of systemic antibiotics and corticosteroids.

Noninflammatory Stress-Induced Remodeling of Mandibular Bone: Impact of Age and Pregnancy.

PURPOSE: The impact of noninflammatory stress, such as aging and pregnancy, on human long bone remodeling is well-established, but little is known about the impact of these stressors on oral bones, including the mandibular bone. To begin to fill this gap in our knowledge, we utilized a mouse mandibular model to evaluate the impact of noninflammatory simple stressors, ie, aging and pregnancy, on bone mandibular architecture and bone density in the mandible using micro-CT. MATERIALS AND METHODS: For the present study, mandibles were obtained from both aged and pregnant C57BL/6 mice and analyzed using micro-CT technology. Micro-CT metrics included bone volume fraction (BVF), total volume (TV), tissue density, and apparent density in the mandible on the mandibular area of compact and trabecular bone, in which the teeth are embedded. All bone-related metrics data from aged and pregnant mice were analyzed using ANOVA analysis and visualized in boxplots. RESULTS: Age-dependent bone remodeling occurred over 4 to 18 weeks of age, ie, increases in BVF, TV, BV/TV, as well as tissue and bone density. Evaluation of bone remodeling in breeder mice (repeated pregnancy model) and virgin mice (age-matched controls) at 37 weeks of age demonstrated that breeder mice had a dramatic decline in all bone metrics measured. CONCLUSIONS: This study underscores the need for more research on noninflammatory stress-related mandibular bone remodeling (eg, age and pregnancy), which compromises bone strength and tooth anchoring. The data also underscores loss of alveolar bone height, as in periodontitis, is an important metric for a more complete assessment of bone loss. This report on mice provides essential data that can be applied for oral-maxillofacial surgeons and periodontists when planning for dental implants in patients with such stressors. Periodontitis related bone loss occurs independent of skeletal homeostasis, although osteoporosis may adversely affect alveolar bone height in humans.

Vitamin Analysis Comparison Study.

PURPOSE: We compared and analyzed the concentrations of vitamin C, vitamin E, zinc, and copper in both national and regional brands of dietary supplements recommended for patients who are at risk for macular degeneration. DESIGN: Prospective cross-sectional study. METHODS: National brand name and generic multivitamin formulations for age-related macular degeneration were obtained. Comparative analysis of the vitamin C and vitamin E content was performed by gas chromatography-mass spectrometry and the zinc and copper content was analyzed by atomic absorption spectroscopy in an institutional chemistry laboratory. RESULTS: All national brand name vitamins, both tablet and gel capsule formulations, and generic brands in tablet form were relatively accurate in their product labeling. For most of the samples tested, the measured quantities of vitamin C, vitamin E, zinc, and copper were slightly higher than labeled but not to an amount that would cause any systemic toxicity if taken at the recommended dosages. CONCLUSIONS: Physicians may recommend national brand name vitamins and generic brands in tablet form to their patients with some confidence; however, the content may have some inaccuracies regarding labeling.

Lighting conditions and perceived visual function in ophthalmic conditions.

PURPOSE: To determine the influence of different lighting conditions on perceived visual function in patients of different age, gender, race, and in various ophthalmic diseases. METHODS: A prospective study. A survey given to patients seen in general ophthalmic and retina clinics. Patients were asked four questions: Is your vision better, worse, or the same in (1) bright light vs dim light, (2) indoors or outdoors, (3) beginning or end of the day, and (4) sunny or cloudy day? Parameters tested were age, race, gender, visual acuity, and a variety of ophthalmic conditions. Multivariable models for each question were fit using multinomial regression. Association was considered significant if p < 0.05. RESULTS: A total of 722 patients were enrolled in the study. Patients with lower vision (LogMAR ≥ 0.3) were more likely to indicate they either had better vision indoors or outdoors compared with better vision patients (LogMAR < 0.1). Patients with pseudophakia were also more likely to indicate they had better vision on a cloudy day (OR = 1.9). White patients had double the odds of selecting bright light compared with others. Males were less likely than females to indicate better vision indoors (OR = 0.62). There were no significant associations with age-related macular degeneration (AMD) in the multivariable model. CONCLUSIONS: Most patients did not note any difference in lighting conditions, and although there is explanatory rational for some of the findings in this study, those questions concerning lighting conditions or time of day are not useful for screening of disease. Gender and ethnicity were found to have associations with lighting preferences which needs to be further studied.

Being Precise About Precision Medicine: What Should Value Frameworks Incorporate to Address Precision Medicine? A Report of the Personalized Precision Medicine Special Interest Group.

Precision medicine is a dynamic area embracing a diverse and increasing type of approaches that allow the targeting of new medicines, screening programs or preventive healthcare strategies, which include the use of biologic markers or complex tests driven by algorithms also potentially taking account of patient preferences. The International Society for Pharmacoeconomics and Outcome Research expanded its current work around precision medicine to (1) describe the evolving paradigm of precision medicine with examples of current and evolving applications, (2) describe key stakeholders perspectives on the value of precision medicine in their respective domains, and (3) define the core factors that should be considered in a value assessment framework for precision medicine. With the ultimate goal of improving health of well-defined patient groups, precision medicine will affect all stakeholders in the healthcare system at multiple levels spanning the individual perspective to the societal perspective. For an efficient, timely and practical precision medicine value assessment framework, it will be important to address these multiple perspectives through building consensus among the stakeholders for robust procedures and measures of value aspects, including performance of precision mechanism; aligned reimbursement processes of precision mechanism and subsequent treatment; transparent expectations for evidence requirements and study designs adequately matched to the intended use of the precision mechanism and to the smaller target patient populations; recognizing the potential range of value-generation such as ruling-in and ruling-out decisions.

Incidence of Serious Infections and Design of Utilization and Safety Studies for Biologic and Biosimilar Surveillance.

BACKGROUND: There is a need for postmarketing evidence generation for novel biologics and biosimilars. OBJECTIVE: To assess the feasibility, strengths, and limitations of the Biologics and Biosimilars Collective Intelligence Consortium (BBCIC) Distributed Research Network (DRN) to examine the utilization and comparative safety of immune-modulating agents among patients with autoimmune diseases. METHODS: We conducted a retrospective cohort study among patients enrolled in health insurance plans participating in the BBCIC DRN between January 1, 2006, and September 30, 2015. Eligible patients were adult (≥18 years) new users of a disease-modifying nonbiologic and/or biologic agent with a prior diagnosis of rheumatoid arthritis (RA), other inflammatory conditions (psoriasis, psoriatic arthritis, ankylosing spondylitis), or inflammatory bowel disease (IBD). Follow-up started at treatment initiation and ended at the earliest of outcome occurrence (serious infection); treatment discontinuation; or switching, death, disenrollment, or end of study period. The study leveraged the FDA Sentinel System infrastructure for data management and analysis; descriptive statistics of patient characteristics and unadjusted incidence rates of study outcomes during follow-up were calculated. RESULTS: Eligible patient drug episodes included 111,611 with RA (75% female), 61,050 with other inflammatory conditions (51% female), and 30,628 with IBD (52% female). Across all 3 cohorts, approximately half of the patient drug episodes initiated a biologic (50% in RA; 60% in psoriasis, psoriatic arthritis, ankylosing spondylitis; and 55% in IBD). The crude incidence rate of serious infection was 9.8 (9.5-10.0) cases per 100 person-years in RA, 7.1 (6.8-7.5) in other inflammatory conditions, and 14.2 (13.6-14.8) in IBD patients. CONCLUSIONS: This study successfully identified large numbers of new users of biologics and produced results that were consistent with those from earlier published studies. The BBCIC DRN is a potential resource for surveillance of biologics. DISCLOSURES: This study was funded by the Biologics and Biosimilars Collective Intelligence Consortium (BBCIC). HealthCore conducted this study in collaboration with Harvard Pilgrim Health Care. Zhang and Sridhar were employed by HealthCore at the time of this study. Haynes is employed by HealthCore funded by PCORI, the NIH, and the FDA. Barr and Eichelberger were employed by AMCP at the time of this study. Lockhart is employed by the BBCIC. Holmes and Clewell are employed by AbbVie. Accrott is an employee of and shareholder in Amgen. Marshall and Brown are employed by Harvard Pilgrim Health Care. Barr is a shareholder in Roche/Genentech. Curtis has received research grants from and consults with the following: Amgen, AbbVie, BMS, CORRONA, Lilly, Janssen, Myriad, Pfizer, Roche, Regeneron, and UCB. Brown has received research grants from GSK and Pfizer and consulting fees from Bayer, Roche, and Jazz Pharmaceuticals, along with funding from the Reagan-Udall Foundation for the FDA to conduct studies for medical product manufacturers, including Eli Lilly, Novartis, Abbvie, and Merck. Brown is also funded by PCORI, the NIH, and the FDA. McMahill-Walraven subcontracts with Harvard Pilgrim Health Care Institute for public health and safety surveillance distributed data network activtities and with the FDA, GSK, and Pfizer. She also reports fees from Reagan Udall Foundation for the FDA and the Patient Centered Outcomes Research Institute.

Foveal vasculature changes and nonperfusion in patients with diabetes types I and II with no evidence of diabetic retinopathy.

PURPOSE: To analyze the foveal avascular zone (FAZ) in patients with diabetes and no retinopathy vs. controls using OCT angiography (OCT-A). METHODS: Prospective, observational clinical study. Type I and II diabetics with no retinopathy and healthy control patients underwent OCT-A. The FAZ size and capillary density were calculated using Image J and Adobe Photoshop CS8. Statistical analysis was performed using one-way ANOVA with Tukey's multiple comparison test and the Pearson correlation test. RESULTS: Fifty-two eyes of 28 diabetic patients and 28 eyes of 16 healthy controls were enrolled. Type I diabetes patients had a longer disease duration than type II (30.3 ± 10.3 vs. 12.3 ± 9.7 years). The mean superficial capillary plexus (SCP) of the FAZ area was 0.27 ± 0.1, 0.36 ± 0.14, and 0.27 ± 0.12 mm2, for the type I, type II, and controls (p = 0.0058) and was significantly larger in type II diabetics (p < 0.05). The mean DCP (deep capillary plexus) FAZ was significantly larger in type II diabetics vs. controls (0.67 ± 0.2 and 0.52 ± 0.16 mm2 respectively) (p < 0.05). Both type I and type II SCP capillary density were significantly lower than the controls (p < 0.05, p < 0.005), and DCP capillary density was significantly lower in type II vs. controls (p < 0.005). CONCLUSIONS: Type I patients showed fewer changes in the FAZ than the type II group, although their duration of diabetes was longer. Larger studies are needed to better analyze the differences between type I and type II diabetics.

Outcomes After the Use of Silicone Oil in Complex Retinal Detachment Repair.

Purpose: This study compares visual acuity (VA), anatomic outcomes, and complications in eyes that underwent complex retinal detachment (RD) repair in which silicone oil (SO) was retained vs removed. Methods: A retrospective chart review of patients undergoing vitrectomy with SO tamponade. The eyes were divided into 2 groups based upon SO removal or retention. Main outcome measures were corrected VA, anatomic outcomes, and the presence of SO-related complications. Results: Fifty-seven eyes with removed SO and 53 eyes with retained SO were identified. In both groups, the mean best-corrected VA (BCVA) at the final visit was significantly better than at baseline. In the retained-SO group, vision improved from 1.79 ± 0.6 to 1.2 ± 0.7 logarithm of the minimum angle of resolution (logMAR) (Snellen, 20/1200 to 20/350) at the final visit (P < .001). In the removed-SO group, mean BCVA improved from 1.84 ± 0.5 at baseline to 1.55 ± 0.6 logMAR units (Snellen, 20/1400 to 20/700) at the visit preceding SO removal (P < .002) and to 1.43 ± 0.6 logMAR units (Snellen, 20/500) at the final visit (P < .001). Complication rates were similar in both groups, apart from RD, which occurred more frequently in the removed-SO group (P = .03). Conclusions: There was similarity in VA and complications among patients with removed or retained SO. Removal of SO may benefit eyes with SO-related complications, but SO retention may decrease the chance of RD and may be indicated in selected cases.

Methodologic considerations for noninterventional studies of switching from reference biologic to biosimilars.

PURPOSE: As more biosimilars become available in the United States, postapproval noninterventional studies describing biosimilar switching and comparing effectiveness and/or safety between switchers and nonswitchers will play a key role in generating real-world evidence to inform clinical practices and policy decisions. Ensuring sound methodology is critical for making valid inferences from these studies. METHODS: The Biologics and Biosimilars Collective Intelligence Consortium (BBCIC) convened a workgroup consisting of academic researchers, industry scientists, and practicing clinicians to establish best practice recommendations for the conduct of noninterventional studies of biosimilar and reference biologic switching. The workgroup members participated in eight teleconferences between August 2017 and February 2018 to discuss specific topics and build consensus. RESULTS: This report provides workgroup recommendations covering five main considerations relating to noninterventional studies describing reference biologic to biosimilar switching and comparing reference biologic to biosimilars for safety and effectiveness in the presence of switching at treatment initiation and during follow-up: (a) selecting appropriate data sources from a range of available options including insurance claims, electronic health records, and registries; (b) study designs; (c) outcomes of interest including health care utilization and clinical endpoints; (d) analytic approaches including propensity scores, disease risk scores, and instrumental variables; and (e) special considerations including avoiding designs that ignore history of biologic use, avoiding immortal time bias, exposure misclassification, and accounting for postindex switching. CONCLUSION: Recommendations provided in this report provide a framework that may be helpful in designing and critically evaluating postapproval noninterventional studies involving reference biologic to biosimilar switching.

Capture of biologic and biosimilar dispensings in a consortium of U.S.-based claims databases: Utilization of national drug codes and Healthcare Common Procedure Coding System modifiers in medical claims.

PURPOSE: To assess the capture of biologics (originator and biosimilar) in the Biologics and Biosimilars Collective Intelligence Consortium (BBCIC) Distributed Research Network (DRN), with a focus on medical claim National Drug Code (NDC), a new data field, and Healthcare Common Procedure Coding System (HCPCS) modifier. METHODS: We conducted a repeated cross-sectional study among patients with medical and pharmacy benefits enrolled in insurance plans participating in the BBCIC DRN between 1 January 2013 and 30 September 2017. We calculated the proportion of medical claims with ≥1 NDC and identified select biologics using four different approaches: (a) specific HCPCS alone, (b) specific HCPCS and NDC, (c) non-specific HCPCS with NDC, and (d) HCPCS with modifiers (applicable to biosimilars). Numbers of dispensings were calculated for each biologic by approach and select patient and claim characteristics. RESULTS: More than 1.5 million eligible participants contributed approximately 4 million person-years of data, including 1.2 billion medical claims. The proportion of medical claims with ≥1 NDC increased from 1.2% in 2013 to 3.0% in 2017. Medical claim NDCs identified 39% and 28% of vedolizumab dispensed in 2014 and 2015 and 30% of Epogen/Procrit dispensed overall. Out of 26,381 filgrastim biosimilar dispensings identified, 51% had a HCPCS modifier and 12% had a medical claim NDC for Zarxio. HCPCS modifiers and medical claim NDCs were present for 38% and 3% of all infliximab biosimilars dispensed (total n = 1,244). CONCLUSIONS: Medical claim NDC and HCPCS modifier improves identification of select biologics without product-specific HCPCS code, thereby facilitating product-specific biologic research.

Mapping from the International Classification of Diseases (ICD) 9th to 10th Revision for Research in Biologics and Biosimilars Using Administrative Healthcare Data.

PURPOSE: The Centers for Medicare and Medicaid Services (CMS) mandated the transition from ICD-9 to ICD-10 codes on October 1, 2015. Postmarketing surveillance of newly marketed drugs, including novel biologics and biosimilars, requires a robust approach to convert ICD-9 to ICD-10 codes for study variables. We examined three mapping methods for health conditions (HCs) of interest to the Biologics and Biosimilars Collective Intelligence Consortium (BBCIC) and compared their prevalence. METHODS: Using CMS General Equivalence Mappings, we applied forward-backward mapping (FBM) to 108 HCs and secondary mapping (SM) and tertiary mapping (TM) to seven preselected HCs. A physician reviewed the mapped ICD-10 codes. The prevalence of the 108 HCs defined by ICD-9 versus ICD-10 codes was examined in BBCIC's distributed research network (September 1, 2012 to March 31, 2018). We visually assessed prevalence trends of these HCs and applied a threshold of 20% level change in ICD-9 versus ICD-10 prevalence. RESULTS: Nearly four times more ICD-10 codes were mapped by SM and TM than FBM, but most were irrelevant or nonspecific. For conditions like myocardial infarction, SM or TM did not generate additional ICD-10 codes. Through visual inspection, one-fifth of the HCs had inconsistent ICD-9 versus ICD-10 prevalence trends. 13% of HCs had a level change greater than +/-20%. CONCLUSION: FBM is generally the most efficient way to convert ICD-9 to ICD-10 codes, yet manual review of converted ICD-10 codes is recommended even for FBM. The lack of existing guidance to compare the performance of ICD-9 with ICD-10 codes led to challenges in empirically determining the quality of conversions.

Disseminated Nocardiosis with retinal abscess in a patient treated for bullous pemphigoid.

PURPOSE: To report a case of disseminated Nocardiosis with retinal and intracranial lesions. OBSERVATIONS: A 49-year-old woman immunosuppressed because of treatment given for bullous pemphigoid presented with altered mental status and multiple intracranial lesions on imaging. The patient was found to have multiple retinal lesions in both eyes, including a subretinal abscess in the right eye. The patient underwent brain biopsy, confirming Nocardia farcinica histopathologically and in culture. CONCLUSIONS AND IMPORTANCE: Ocular Nocardiosis is a rare disease with varying prognosis that requires prompt diagnosis to ensure appropriate medical therapy.

Correction of: Exploring Concordance of Patient-Reported Information on PatientsLikeMe and Medical Claims Data at the Patient Level.

[This corrects the article DOI: 10.2196/jmir.5130.].

Exploring Concordance of Patient-Reported Information on PatientsLikeMe and Medical Claims Data at the Patient Level.

BACKGROUND: With the emergence of data generated by patient-powered research networks, it is informative to characterize their correspondence with health care system-generated data. OBJECTIVES: This study explored the linking of 2 disparate sources of real-world data: patient-reported data from a patient-powered research network (PatientsLikeMe) and insurance claims. METHODS: Active patients within the PatientsLikeMe community, residing in the United States, aged 18 years or older, with a self-reported diagnosis of multiple sclerosis or Parkinson's disease (PD) were invited to participate during a 2-week period in December 2014. Patient-reported data were anonymously matched and compared to IMS Health medical and pharmacy claims data with dates of service between December 2009 and December 2014. Patient-level match (identity), diagnosis, and usage of disease-modifying therapies (DMTs) were compared between data sources. RESULTS: Among 603 consenting patients, 94% had at least 1 record in the IMS Health dataset; of these, there was 93% agreement rate for multiple sclerosis diagnosis. Concordance on the use of any treatment was 59%, and agreement on reports of specific treatment usage (within an imputed 5-year period) ranged from 73.5% to 100%. CONCLUSIONS: It is possible to match patient identities between the 2 data sources, and the high concordance at multiple levels suggests that the matching process was accurate. Likewise, the high degree of concordance suggests that these patients were able to accurately self-report their diagnosis and, to a lesser degree, their treatment usage. Further studies of linked data types are warranted to evaluate the use of enriched datasets to generate novel insights.