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2.
medRxiv ; 2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36203544

RESUMEN

Background: We investigated whether abatacept, a selective costimulation modulator, provides additional benefit when added to standard-of-care for patients hospitalized with Covid-19. Methods: We conducted a master protocol to investigate immunomodulators for potential benefit treating patients hospitalized with Covid-19 and report results for abatacept. Intravenous abatacept (one-time dose 10 mg/kg, maximum dose 1000 mg) plus standard of care (SOC) was compared with shared placebo plus SOC. Primary outcome was time-to-recovery by day 28. Key secondary endpoints included 28-day mortality. Results: Between October 16, 2020 and December 31, 2021, a total of 1019 participants received study treatment (509 abatacept; 510 shared placebo), constituting the modified intention-to-treat cohort. Participants had a mean age 54.8 (SD 14.6) years, 60.5% were male, 44.2% Hispanic/Latino and 13.7% Black. No statistically significant difference for the primary endpoint of time-to-recovery was found with a recovery-rate-ratio of 1.14 (95% CI 1.00-1.29; p=0.057) compared with placebo. We observed a substantial improvement in 28-day all-cause mortality with abatacept versus placebo (11.0% vs. 15.1%; odds ratio [OR] 0.62 [95% CI 0.41- 0.94]), leading to 38% lower odds of dying. Improvement in mortality occurred for participants requiring oxygen/noninvasive ventilation at randomization. Subgroup analysis identified the strongest effect in those with baseline C-reactive protein >75mg/L. We found no statistically significant differences in adverse events, with safety composite index slightly favoring abatacept. Rates of secondary infections were similar (16.1% for abatacept; 14.3% for placebo). Conclusions: Addition of single-dose intravenous abatacept to standard-of-care demonstrated no statistically significant change in time-to-recovery, but improved 28-day mortality. Trial registration: ClinicalTrials.gov ( NCT04593940 ).

3.
medRxiv ; 2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36172138

RESUMEN

Background: Immune dysregulation contributes to poorer outcomes in severe Covid-19. Immunomodulators targeting various pathways have improved outcomes. We investigated whether infliximab provides benefit over standard of care. Methods: We conducted a master protocol investigating immunomodulators for potential benefit in treatment of participants hospitalized with Covid-19 pneumonia. We report results for infliximab (single dose infusion) versus shared placebo both with standard of care. Primary outcome was time to recovery by day 29 (28 days after randomization). Key secondary endpoints included 14-day clinical status and 28-day mortality. Results: A total of 1033 participants received study drug (517 infliximab, 516 placebo). Mean age was 54.8 years, 60.3% were male, 48.6% Hispanic or Latino, and 14% Black. No statistically significant difference in the primary endpoint was seen with infliximab compared with placebo (recovery rate ratio 1.13, 95% CI 0.99-1.29; p=0.063). Median (IQR) time to recovery was 8 days (7, 9) for infliximab and 9 days (8, 10) for placebo. Participants assigned to infliximab were more likely to have an improved clinical status at day 14 (OR 1.32, 95% CI 1.05-1.66). Twenty-eight-day mortality was 10.1% with infliximab versus 14.5% with placebo, with 41% lower odds of dying in those receiving infliximab (OR 0.59, 95% CI 0.39-0.90). No differences in risk of serious adverse events including secondary infections. Conclusions: Infliximab did not demonstrate statistically significant improvement in time to recovery. It was associated with improved 14-day clinical status and substantial reduction in 28- day mortality compared with standard of care. Trial registration: ClinicalTrials.gov ( NCT04593940 ).

4.
Infection ; 47(6): 945-953, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31111325

RESUMEN

PURPOSE: Many patients with suspected meningitis do not require hospitalization yet are admitted, often resulting in unnecessary care and additional cost. We assessed the possible economic impact of a rapid multiplex test for suspected adult community-acquired meningitis/encephalitis. METHODS: A model simulated diagnosis, clinical decisions, resource use/costs of standard of care (SOC) and two cerebrospinal fluid (CSF) testing strategies using the FDA-cleared BioFire® FilmArray® System (FA) which provides results in approximately one hour. RESULTS: Pathogens detected by FA caused approximately 74% of cases, 97% of which would be accurately diagnosed with FA. False positives and false negatives more often led to extended/unnecessary admission than inappropriate discharge/missed admission. Mean cost per case ranged from 16829 to 20791. A strategy of testing all suspected cases yielded greater savings (2213/case) than testing only those with abnormal CSF (812/case) and both were less expensive than SOC. CONCLUSION: This economic analysis demonstrates that FA can inform more appropriate clinician decisions resulting in cost savings with greater economic benefits achievable with syndromic testing of all cases, rather than SOC or targeted syndromic testing.


Asunto(s)
Encefalitis/diagnóstico , Meningitis/diagnóstico , Reacción en Cadena de la Polimerasa Multiplex/economía , Adulto , Anciano , Anciano de 80 o más Años , Humanos , Persona de Mediana Edad , Adulto Joven
5.
Future Microbiol ; 13: 617-629, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29316801

RESUMEN

AIM: We assessed the possible economic impact of a rapid test in pediatric patients with suspected community-acquired meningitis/encephalitis. MATERIALS & METHODS: Modeling simulated diagnosis, clinical decisions, resource use/costs of standard of care (SOC) and two cerebrospinal fluid testing strategies using FilmArray® (FA), a US FDA-cleared system that provides results in approximately 1 h. RESULTS: Pathogens detected by FA caused approximately 75% of cases, 97% of which would be accurately diagnosed with FA.  Mean cost/case ranged from $17,599 to $22,025.  Syndromic testing is less expensive than SOC. Testing all suspected cases yielded greater savings ($3481/case) than testing only those with abnormal cerebrospinal fluid ($2157/case). CONCLUSION: Greater economic benefits are achievable with syndromic testing of all cases, rather than SOC or targeted syndromic testing.


Asunto(s)
Costos y Análisis de Costo , Encefalitis/diagnóstico , Meningitis/diagnóstico , Técnicas de Diagnóstico Molecular/economía , Técnicas de Diagnóstico Molecular/métodos , Reacción en Cadena de la Polimerasa Multiplex/economía , Reacción en Cadena de la Polimerasa Multiplex/métodos , Adolescente , Niño , Preescolar , Infecciones Comunitarias Adquiridas/diagnóstico , Humanos , Lactante , Recién Nacido , Modelos Estadísticos , Factores de Tiempo
7.
Chest ; 151(1): 23-33, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27568580

RESUMEN

BACKGROUND: There is a growing use of procalcitonin (PCT) to facilitate the diagnosis and management of severe sepsis. We investigated the impact of one to two PCT determinations on ICU day 1 on health-care utilization and cost in a large research database. METHODS: A retrospective, propensity score-matched multivariable analysis was performed on the Premier Healthcare Database for patients admitted to the ICU with one to two PCT evaluations on day 1 of ICU admission vs patients who did not have PCT testing. RESULTS: A total of 33,569 PCT-managed patients were compared with 98,543 propensity score-matched non-PCT patients. In multivariable regression analysis, PCT utilization was associated with significantly decreased total length of stay (11.6 days [95% CI, 11.4 to 11.7] vs 12.7 days [95% CI, 12.6 to 12.8]; 95% CI for difference, 1 to 1.3; P < .001) and ICU length of stay (5.1 days [95% CI, 5.1 to 5.2] vs 5.3 days [95% CI, 5.3 to 5.4]; 95% CI for difference, 0.1 to 0.3; P < .03), and lower hospital costs ($30,454 [95% CI, 29,968 to 31,033] vs $33,213 [95% CI, 32,964 to 33,556); 95% CI for difference, 2,159 to 3,321; P < .001). There was significantly less total antibiotic exposure (16.2 days [95% CI, 16.1 to 16.5] vs 16.9 days [95% CI, 16.8 to 17.1]; 95% CI for difference, -0.9 to 0.4; P = .006) in PCT-managed patients. Patients in the PCT group were more likely to be discharged to home (44.1% [95% CI, 43.7 to 44.6] vs 41.3% [95% CI, 41 to 41.6]; 95% CI for difference, 2.3 to 3.3; P = .006). Mortality was not different in an analysis including the 96% of patients who had an independent measure of mortality risk available (19.1% [95% CI, 18.7 to 19.4] vs 19.1% [95% CI, 18.9 to 19.3]; 95% CI for difference, -0.5 to 0.4; P = .93). CONCLUSIONS: Use of PCT testing on the first day of ICU admission was associated with significantly lower hospital and ICU lengths of stay, as well as decreased total, ICU, and pharmacy cost of care. Further elucidation of clinical outcomes requires additional data.


Asunto(s)
Calcitonina/farmacología , Pruebas de Química Clínica , Enfermedad Crítica , Sepsis , Anciano , Conservadores de la Densidad Ósea/farmacología , Pruebas de Química Clínica/métodos , Pruebas de Química Clínica/estadística & datos numéricos , Análisis Costo-Beneficio , Enfermedad Crítica/epidemiología , Enfermedad Crítica/terapia , Demografía , Femenino , Humanos , Unidades de Cuidados Intensivos/estadística & datos numéricos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Puntaje de Propensión , Estudios Retrospectivos , Sepsis/diagnóstico , Sepsis/mortalidad , Factores Socioeconómicos , Estados Unidos/epidemiología
8.
J Acquir Immune Defic Syndr ; 68(2): 133-9, 2015 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-25383710

RESUMEN

BACKGROUND: Attendance at biannual medical encounters has been proposed as a minimum national standard for adequate engagement in HIV care. Using data from the HIV Outpatient Study, we analyzed how well dates of HIV-related laboratory testing correlated with attendance at biannual medical encounters. METHODS: HIV Outpatient Study is an open prospective cohort study of HIV-infected patients receiving outpatient care in the United States. The data set included dates for laboratory measurements and medical encounters. We included patients with at least 1 HIV laboratory test (CD4 cell count or plasma HIV RNA viral load) during 2010-2011. An HIV laboratory test was defined as associated with a medical encounter if it occurred within 3 weeks of the encounter. We assessed the predictive value of HIV laboratory tests as a proxy for adequate engagement in clinical care, defined as having had ≥2 HIV laboratory tests within 1 year and performed >90 days apart. RESULTS: A total of 10,321 HIV laboratory tests were recorded from 2909 patients. Adequate engagement in clinical care based on medical encounters was 88.2% and 77.3% when based on laboratory tests. Using HIV laboratory tests to assess engagement had a sensitivity of 85.7%, specificity of 86.0%, and positive and negative predictive values of 97.9% and 44.5%, respectively. Of the 22.7% classified as not engaged in care by the proxy measure, over half (55.5%) were actually engaged. CONCLUSIONS: Using laboratory monitoring reliably classified persons as engaged in care. Of the 22.7% of patients classified as not engaged in care, most were actually engaged.


Asunto(s)
Técnicas de Laboratorio Clínico/métodos , Pruebas Diagnósticas de Rutina/métodos , Infecciones por VIH/patología , Adolescente , Adulto , Anciano , Recuento de Linfocito CD4 , Estudios de Cohortes , Femenino , VIH/aislamiento & purificación , Infecciones por VIH/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Pacientes Ambulatorios , Cooperación del Paciente , Estudios Prospectivos , Estados Unidos , Carga Viral , Adulto Joven
9.
Clinicoecon Outcomes Res ; 5: 507-17, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24187506

RESUMEN

BACKGROUND: Lipid-based formulations of amphotericin B (LF-AMB) are indicated for treatment of invasive fungal infections in patients intolerant to conventional amphotericin B (CAB) or with refractory infections. Physicians still may choose to administer CAB to such patients. We described the use of CAB and LF-AMB in this population and quantified differences in post-amphotericin B length of stay (LOS) among survivors and hospital mortality in matched patients. METHODS: Data were extracted from Health Facts (Cerner Corporation, Kansas City, MO, USA) for a retrospective cohort analysis. Inpatients aged ≥18 years with evidence of fungal infection and with orders for LF-AMB or CAB on ≥2 days from January 2001 to June 2010 were identified. Patients were required to have renal insufficiency or other relative contraindications to use of CAB, exposure to nephrotoxic agents, or evidence of a CAB-refractory infection. Multilevel (hierarchical) mixed-effects logistic regression was used to determine factors associated with initial exposure to LF-AMB versus CAB. Multivariate adjustment of outcomes was done using propensity score matching. RESULTS: 655 patients were identified: 322 patients initiated therapy with CAB and 333 initiated treatment with LF-AMB. Compared to those initiating CAB, patients initiating LF-AMB had greater acuity and underlying disease severity. In unadjusted analyses, hospital mortality was significantly higher in the LF-AMB group (32.2% versus 23.7%; P = 0.02). After propensity score matching and covariate adjustment, mortality equalized and observed differences in LOS after amphotericin B initiation decreased. CONCLUSION: Among patients at risk for amphotericin B toxicity, differences between CAB and LF-AMB seen in crude outcomes analyses relate to channeling of sicker patients to initiate treatment with LF-AMB. Failing to account for differences among patients that drive clinical decision-making will result in inaccurate conclusions about the real-world effectiveness of different amphotericin B formulations.

10.
Open AIDS J ; 6: 67-76, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23049655

RESUMEN

Epidemiologic and clinical changes in the HIV epidemic over time have presented a challenge to public health surveillance to monitor behavioral and clinical factors that affect disease progression and HIV transmission. The Medical Monitoring Project (MMP) is a supplemental surveillance project designed to provide representative, population-based data on clinical status, care, outcomes, and behaviors of HIV-infected persons receiving care at the national level. We describe a three-stage probability sampling method that provides both nationally and state-level representative estimates.In stage-I, 20 states, which included 6 separately funded cities/counties, were selected using probability proportional to size (PPS) sampling. PPS sampling was also used in stage-II to select facilities for participation in each of the 26 funded areas. In stage-III, patients were randomly selected from sampled facilities in a manner that maximized the possibility of having overall equal selection probabilities for every patient in the state or city/county. The sampling methods for MMP could be adapted to other research projects at national or sub-national levels to monitor populations of interest or evaluate outcomes and care for a range of specific diseases or conditions.

13.
Med Mycol ; 46(4): 393-5, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18415850

RESUMEN

An all oral treatment for cryptococcal meningitis is attractive, particularly where amphotericin B use is impractical. Both fluconazole and flucytosine are available in oral formulations and have activity against Cryptococcus neoformans. We conducted a prospective phase II dose escalation study employing doses of fluconazole ranging from 800 to 2000 mg daily for 10 weeks used alone or combined with flucytosine at 100 mg/kg per day for the first 4 weeks. We found that increasing doses of fluconazole were associated with an increase in survival and a decrease in the time to conversion of the cerebrospinal fluid from culture positive to culture negative. Addition of flucytosine to fluconazole improved outcomes in each dosing cohort. High doses of fluconazole alone or combined with flucytosine were well tolerated.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Antifúngicos/uso terapéutico , Fluconazol/uso terapéutico , Flucitosina/uso terapéutico , Meningitis Criptocócica/tratamiento farmacológico , Infecciones Oportunistas Relacionadas con el SIDA/líquido cefalorraquídeo , Administración Oral , Adulto , Antifúngicos/efectos adversos , Estudios de Cohortes , Relación Dosis-Respuesta a Droga , Quimioterapia Combinada , Fluconazol/efectos adversos , Flucitosina/efectos adversos , Humanos , Masculino , Meningitis Criptocócica/líquido cefalorraquídeo , Náusea/inducido químicamente , Estudios Prospectivos , Resultado del Tratamiento , Vómitos/inducido químicamente
14.
J Acquir Immune Defic Syndr ; 47(3): 338-41, 2008 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-18176330

RESUMEN

There is continuing interest in the longer term effects of highly active antiretroviral therapy (HAART) on the risk of cardiopulmonary events. We assessed this using updated administrative data from an open retrospective cohort of HIV-infected persons receiving care from the US Veterans Affairs (VA). Information on 41,213 HIV-infected patients receiving VA care between January 1993 and December 2003 was included. Patients were followed for an average of 4 years or 168,213 person-years of follow-up. The death rate fell from 20.9 deaths per 100 patient-years of observation in 1995 to 5.2 deaths per 100 patient-years in 2003. In patient-level analysis, adjusted hazard ratios for death dropped precipitously for all races to a low of 0.18 (95% confidence interval: 0.15 to 0.23) at 72 months of exposure to HAART. Hazards for serious cardiovascular events remained near 1.0 for exposure to HAART, and hazards for serious cardiovascular events, stroke, or death were only slightly higher than for death alone. No selection effects or secular trends were found. The benefits of HAART continued to increase in the 8 years after introduction and with 6 years of individual use. The risk of serious cardiovascular events should be factored into individual patient management but does not pose an important public health risk.


Asunto(s)
Terapia Antirretroviral Altamente Activa , Enfermedades Cardiovasculares/mortalidad , Infecciones por VIH/tratamiento farmacológico , Veteranos/estadística & datos numéricos , Adulto , Fármacos Anti-VIH/efectos adversos , Fármacos Anti-VIH/uso terapéutico , Enfermedades Cardiovasculares/etiología , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Infecciones por VIH/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tasa de Supervivencia/tendencias , Factores de Tiempo , Estados Unidos
15.
Am J Public Health ; 97(12): 2173-8, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17971545

RESUMEN

OBJECTIVES: We sought to determine the prevalence of HIV in both inpatient and outpatient settings in 6 Department of Veterans Affairs (VA) health care sites. METHODS: We collected demographic data and data on comorbid conditions and then conducted blinded, anonymous HIV testing. We conducted a multivariate analysis to determine predictors of HIV infection. RESULTS: We tested 4500 outpatient blood specimens and 4205 inpatient blood specimens; 326 (3.7%) patients tested positive for HIV. Inpatient HIV prevalence ranged from 1.2% to 6.9%; outpatient HIV prevalence ranged from 0.9% to 8.9%. Having a history of hepatitis B or C infection, a sexually transmitted disease, or pneumonia also predicted HIV infection. The prevalence of previously undocumented HIV infection varied from 0.1% to 2.8% among outpatients and from 0.0% to 1.7% among inpatients. CONCLUSIONS: The prevalence of undocumented HIV infection was sufficiently high for routine voluntary screening to be cost effective in each of the 6 sites we evaluated. Many VA health care systems should consider expanded routine voluntary HIV screening.


Asunto(s)
Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Seroprevalencia de VIH , Tamizaje Masivo , Veteranos , Adulto , Anciano , Comorbilidad , Análisis Costo-Beneficio , Humanos , Tamizaje Masivo/economía , Persona de Mediana Edad , Análisis Multivariante , Estados Unidos/epidemiología , United States Department of Veterans Affairs/estadística & datos numéricos , Veteranos/estadística & datos numéricos
16.
BMC Public Health ; 7: 208, 2007 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-17697389

RESUMEN

BACKGROUND: In an influenza pandemic, the benefit of vaccines and antiviral medications will be constrained by limitations on supplies and effectiveness. Non-pharmaceutical public health interventions will therefore be vital in curtailing disease spread. However, the most comprehensive assessments of the literature to date recognize the generally poor quality of evidence on which to base non-pharmaceutical pandemic planning decisions. In light of the need to prepare for a possible pandemic despite concerns about the poor quality of the literature, combining available evidence with expert opinion about the relative merits of non-pharmaceutical interventions for pandemic influenza may lead to a more informed and widely accepted set of recommendations. We evaluated the evidence base for non-pharmaceutical public health interventions. Then, based on the collective evidence, we identified a set of recommendations for and against interventions that are specific to both the setting in which an intervention may be used and the pandemic phase, and which can be used by policymakers to prepare for a pandemic until scientific evidence can definitively respond to planners' needs. METHODS: Building on reviews of past pandemics and recent historical inquiries, we evaluated the relative merits of non-pharmaceutical interventions by combining available evidence from the literature with qualitative and quantitative expert opinion. Specifically, we reviewed the recent scientific literature regarding the prevention of human-to-human transmission of pandemic influenza, convened a meeting of experts from multiple disciplines, and elicited expert recommendation about the use of non-pharmaceutical public health interventions in a variety of settings (healthcare facilities; community-based institutions; private households) and pandemic phases (no pandemic; no US pandemic; early localized US pandemic; advanced US pandemic). RESULTS: The literature contained a dearth of evidence on the efficacy or effectiveness of most non-pharmaceutical interventions for influenza. In an effort to inform decision-making in the absence of strong scientific evidence, the experts ultimately endorsed hand hygiene and respiratory etiquette, surveillance and case reporting, and rapid viral diagnosis in all settings and during all pandemic phases. They also encouraged patient and provider use of masks and other personal protective equipment as well as voluntary self-isolation of patients during all pandemic phases. Other non-pharmaceutical interventions including mask-use and other personal protective equipment for the general public, school and workplace closures early in an epidemic, and mandatory travel restrictions were rejected as likely to be ineffective, infeasible, or unacceptable to the public. CONCLUSION: The demand for scientific evidence on non-pharmaceutical public health interventions for influenza is pervasive, and present policy recommendations must rely heavily on expert judgment. In the absence of a definitive science base, our assessment of the evidence identified areas for further investigation as well as non-pharmaceutical public health interventions that experts believe are likely to be beneficial, feasible and widely acceptable in an influenza pandemic.


Asunto(s)
Control de Enfermedades Transmisibles/métodos , Brotes de Enfermedades/prevención & control , Medicina Basada en la Evidencia , Gripe Humana/prevención & control , Administración en Salud Pública , Consenso , Política de Salud , Humanos , Gripe Humana/diagnóstico , Gripe Humana/epidemiología
17.
J Gen Intern Med ; 22(3): 315-20, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17356961

RESUMEN

OBJECTIVE: Early identification of HIV infection is critical for patients to receive life-prolonging treatment and risk-reduction counseling. Understanding HIV screening practices and barriers to HIV testing is an important prelude to designing successful HIV screening programs. Our objective was to evaluate current practice patterns for identification of HIV. METHODS: We used a retrospective cohort analysis of 13,991 at-risk patients seen at 4 large Department of Veterans Affairs (VA) health-care systems. We also reviewed 1,100 medical records of tested patients. We assessed HIV testing rates among at-risk patients, the rationale for HIV testing, and predictors of HIV testing and of HIV infection. RESULTS: Of the 13,991 patients at risk for HIV, only 36% had been HIV-tested. The prevalence of HIV ranged from 1% to 20% among tested patients at the 4 sites. Approximately 90% of patients who were tested had a documented reason for testing. CONCLUSION: One-half to two-thirds of patients at risk for HIV had not been tested within our selected VA sites. Among tested patients, the rationale for HIV testing was well documented. Further testing of at-risk patients could clearly benefit patients who have unidentified HIV infection by providing earlier access to life-prolonging therapy.


Asunto(s)
Prestación Integrada de Atención de Salud/métodos , Infecciones por VIH/epidemiología , Tamizaje Masivo/métodos , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Infecciones por VIH/sangre , Infecciones por VIH/diagnóstico , Seropositividad para VIH/sangre , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Estados Unidos , United States Department of Veterans Affairs
18.
Stat Med ; 26(10): 2184-202, 2007 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-16998829

RESUMEN

Interval-censored, or more generally, coarsened event-time data arise when study participants are observed at irregular time periods and experience the event of interest in between study observations. Such data are often analysed assuming non-informative censoring, which can produce biased results if the assumption is wrong. This paper extends the standard approach for estimating survivor functions to allow informatively interval-censored data by incorporating various assumptions about the censoring mechanism into the model. We include a Bayesian extension in which final estimates are produced by mixing over a distribution of assumed censoring mechanisms. We illustrate these methods with a natural history study of HIV-infected individuals using assumptions elicited from an AIDS expert.


Asunto(s)
Interpretación Estadística de Datos , Análisis de Supervivencia , Teorema de Bayes , Infecciones por VIH , Humanos , Factores de Tiempo , Estados Unidos
19.
Jt Comm J Qual Patient Saf ; 32(6): 324-36, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16776387

RESUMEN

BACKGROUND: Many organizations participate in quality collaboratives, yet the return on investment of the associated time and costs is unclear. METHOD: Semistructured interviews, surveys, and direct observation were used to assess experiences, improvement activities, and costs associated with participation in a year-long modified Institute for Healthcare Improvement-style collaborative designed to improve HIV care within the Veterans Health Administration. All nine sites had access to automated patient registries and semi-automated clinical measure reports; five sites also received computerized clinical reminders. Three one-day learning sessions were conducted. RESULTS: Participants reported that burden was small and value high, although many suggested that more time for peer-to peer learning would have been helpful. Teams averaged five quality improvement activities per site and most reported improvements in HIV care processes. The average annual cost per site was dollars 28,000 but costs varied considerably by site. DISCUSSION: Shortened learning sessions and the incorporation of health information technology can reduce some of the costs and burdens associated with collaboratives, yet peer-to-peer interaction and local organizational factors remain important to ensuring perceived effectiveness of collaboratives.


Asunto(s)
Conducta Cooperativa , Infecciones por VIH/terapia , Sistemas de Información/estadística & datos numéricos , Garantía de la Calidad de Atención de Salud/organización & administración , United States Department of Veterans Affairs/organización & administración , Infecciones por VIH/economía , Humanos , Sistemas de Información/economía , Educación del Paciente como Asunto , Garantía de la Calidad de Atención de Salud/economía , Sistemas Recordatorios , Estados Unidos , United States Department of Veterans Affairs/economía
20.
BMC Public Health ; 6: 126, 2006 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-16677388

RESUMEN

BACKGROUND: Because smallpox (variola major) may be used as a biological weapon, we reviewed outbreaks in post-World War II Europe and North America in order to understand smallpox transmission patterns. METHODS: A systematic review was used to identify papers from the National Library of Medicine, Embase, Biosis, Cochrane Library, Defense Technical Information Center, WorldCat, and reference lists of included publications. Two authors reviewed selected papers for smallpox outbreaks. RESULTS: 51 relevant outbreaks were identified from 1,389 publications. The median for the effective first generation reproduction rate (initial R) was 2 (range 0-38). The majority outbreaks were small (less than 5 cases) and contained within one generation. Outbreaks with few hospitalized patients had low initial R values (median of 1) and were prolonged if not initially recognized (median of 3 generations); outbreaks with mostly hospitalized patients had higher initial R values (median 12) and were shorter (median of 3 generations). Index cases with an atypical presentation of smallpox were less likely to have been diagnosed with smallpox; outbreaks in which the index case was not correctly diagnosed were larger (median of 27.5 cases) and longer (median of 3 generations) compared to outbreaks in which the index case was correctly diagnosed (median of 3 cases and 1 generation). CONCLUSION: Patterns of spread during Smallpox outbreaks varied with circumstances, but early detection and implementation of control measures is a most important influence on the magnitude of outbreaks. The majority of outbreaks studied in Europe and North America were controlled within a few generations if detected early.


Asunto(s)
Control de Enfermedades Transmisibles/tendencias , Brotes de Enfermedades/prevención & control , Viruela/epidemiología , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones Comunitarias Adquiridas/prevención & control , Infección Hospitalaria/epidemiología , Infección Hospitalaria/prevención & control , Brotes de Enfermedades/clasificación , Brotes de Enfermedades/estadística & datos numéricos , Europa (Continente)/epidemiología , Humanos , América del Norte/epidemiología , Viruela/prevención & control , Viruela/transmisión , Cambio Social , Segunda Guerra Mundial
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