RESUMO
OBJECTIVE: To examine the association between intersectionality of race, ethnicity, and sex on retention of U.S. general surgery residents. SUMMARY BACKGROUND DATA: There are limited data on the role that intersectionality plays on the US general surgery resident experience. METHODS: Analysis was performed using Association of American Medical Colleges (AAMC) data for general surgery residents who started their training between 2005-2015 (followed through completion). Regression analyses were used to assess demographic associations with time to attrition or successful completion of residency training. Associations between faculty and resident demographics were assessed. RESULTS: 25,029 residents were included. Over the decade-long study period, the number of underrepresented in medicine (UIM) residents as a percentage of all residents remained similar from 17% to 19% (P=0.24). The percent of UIM males starting training in 2005 was 11% and 12% in 2015 (P-value=0.38). UIM females comprised 5.5% of trainees in 2005 and increased to 6.9% (P-value=0.003) in 2015; and female non-UIM residents increased from 23 to 28% (P-value<0.001). The overall rate of resident attrition was 15%. UIM females had the highest yearly attrition rate at 21% compared to non-UIM males at 13% (HR 1.7, P<0.001). UIM females were more likely to leave residency compared to UIM males (HR: 1.5; P<0.001). The percent of UIM faculty was positively correlated with percent of UIM residents (r=0.64, P<0.001). CONCLUSIONS: Increasing intersectionality is positively associated with attrition during surgery residency. The diversity of faculty appears to be associated with resident diversity.
RESUMO
BACKGROUND: Asian American (AsAm) women have some of the lowest rates of up-to-date breast cancer screening, and lack of disaggregated racial/ethnic data can mask disparities. We evaluated presentation patterns among AsAms at two hospitals with distinct communities: New York Presbyterian-Queens (NYPQ), in Flushing, Queens and Weill Cornell Medical Center (WCM), on the Upper East Side (UES) neighborhood of Manhattan. PATIENTS AND METHODS: Patients with newly diagnosed breast cancer between January 2019 and December 2022 were identified using a prospective database and clinical data collected. Patients were categorized as self-reported Asian versus Non-Asian. The Asian group was disaggregated as Chinese-Asian versus Other-Asian. Physician workforce data were obtained from public records. RESULTS: A total of 3546 patients (1162 NYPQ, 2384 WCM) were included. More NYPQ patients identified as Asian compared with WCM (49 vs. 14%, p < 0.001). Asian patients were mostly East Asian Chinese (NYPQ 61%, WCM 53%). More Chinese patients at NYPQ reported Chinese as their preferred language (81 vs. 33%, p < 0.001). Greatest differences of screen-detected disease frequency were seen between NYPQ and WCM Chinese patients (75 vs. 59%, p < 0.001). Eighty percent of NYPQ Chinese patients presented with stage 0/I disease versus 69% at WCM (p = 0.007), a difference not observed between Other-Asian patients (75% NYPQ, 68% WCM, p = 0.095). 3% of UES physicians versus 16% in Flushing reported speaking Chinese. CONCLUSIONS: Chinese patients residing in a neighborhood with more Chinese-speaking physicians more frequently presented with screen-detected, early-stage breast cancer. Stage distribution differences were not apparent among the aggregated pool of Other-Asian patients, suggesting cancer disparities may be masked when ethnic groups are studied in aggregate.
Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico , Asiático , Cidade de Nova Iorque , Incidência , Detecção Precoce de CâncerRESUMO
INTRODUCTION: Breast cancer (BC) incidence has been increasing among Asian-Americans (AsAms); recent data suggest these patients are less likely to undergo postmastectomy breast reconstruction (PMBR) compared to non-Asian women. Historically, AsAm BC patients are reported in aggregate, masking heterogeneity within this population. We aim to identify patterns of postmastectomy reconstruction among disaggregated AsAm BC patients at our institution. METHODS: A retrospective chart review was performed for BC patients who underwent mastectomy between 2017 and 2021. Patient demographic and clinical information was collected including self-reported race/ethnicity and reconstruction at time of mastectomy. Self-identified Asian patients were disaggregated into East Asian, Southeast Asian, South Asian, and 'Asian Other.' We examined rates of reconstruction between the different races and the disaggregated Asian subgroups. Univariable and multivariable analysis was performed to examine patient factors associated with PMBR. RESULTS: Six hundred and five patients met inclusion criteria. Forty seven percent of patients identified as Asian, 36% of which as East Asian. Forty four percent of all patients underwent PMBR. Southeast Asian and South Asian women were least likely to undergo reconstruction, while Hispanic and non-Hispanic Black women were most likely to pursue PMBR (P = 0.020). On multivariable analysis, Hispanic, non-Hispanic White, and non-Hispanic Black women were more likely to undergo reconstruction compared to Asian women. Other factors associated with reconstruction were coverage with private insurance and diagnosis of noninvasive disease. CONCLUSIONS: Rates of PMBR are lower among AsAms than non-Asian patients and vary between Asian ethnic subgroups. Further investigation is needed to identify patterns of reconstruction among the disaggregated AsAm population to address disparities.
Assuntos
Asiático , Neoplasias da Mama , Disparidades em Assistência à Saúde , Mamoplastia , Mastectomia , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Asiático/etnologia , Asiático/estatística & dados numéricos , Neoplasias da Mama/cirurgia , Neoplasias da Mama/etnologia , Disparidades em Assistência à Saúde/estatística & dados numéricos , Disparidades em Assistência à Saúde/etnologia , Mamoplastia/estatística & dados numéricos , Mastectomia/estatística & dados numéricos , Estudos Retrospectivos , População do Leste Asiático , População do Sudeste Asiático , População do Sul da Ásia , Hispânico ou Latino , Negro ou Afro-AmericanoRESUMO
The Asian American Pacific Islander (AAPI) population is a heterogeneous group of people from geographically and ethnically distinct regions of the world. Traditionally, these patients have been reported as one large aggregate in the breast cancer literature under the race category of "Asian." A detailed examination of this group shows compelling evidence that breast cancer manifests differently among Asian ethnic subgroups, resulting in overlooked health disparities when these races are grouped together. The AAPI community is the fastest growing ethnic group in the United States, and their incidence of breast cancer is increasing at rates greater than among their non-Asian counterparts. When these patients are disaggregated by race, they show wide variations in breast cancer screening, presentation, treatment, and outcomes. This population often faces additional unique challenges in the health care system due to cultural, social, health literacy, and language barriers, which can contribute to further disparity. Our landmark series aims to showcase the breadth of the breast cancer burden in the AAPI population and highlight the need for disaggregated ethnic data.
Assuntos
Neoplasias da Mama , Humanos , Estados Unidos/epidemiologia , Feminino , Neoplasias da Mama/prevenção & controle , Asiático , Etnicidade , Detecção Precoce de CâncerRESUMO
Race-related variation in breast cancer incidence and mortality are well-documented in the United States. The effect of genetic ancestry on disparities in tumor genomics, risk factors, treatment, and outcomes of breast cancer is less understood. The Cancer Genome Atlas (TCGA) is a publicly available resource that has allowed for the recent emergence of genome analysis research seeking to characterize tumor DNA and protein expression by ancestry as well as the social construction of race and ethnicity. Results from TCGA based studies support previous clinical evidence that demonstrates that American women with African ancestry are more likely to be afflicted with breast cancers featuring aggressive biology and poorer outcomes compared with women with other backgrounds. Data from TCGA based studies suggest that Asian women have tumors with favorable immune microenvironments and may experience better disease-free survival compared with white Americans. TCGA contains limited data on Hispanic/Latinx patients due to small sample size. Overall, TCGA provides important opportunities to define the molecular, biologic, and germline genetic factors that contribute to breast cancer disparities.
Assuntos
Neoplasias da Mama , DNA de Neoplasias , Disparidades nos Níveis de Saúde , Feminino , Humanos , Asiático/genética , Neoplasias da Mama/etnologia , Neoplasias da Mama/genética , Intervalo Livre de Doença , DNA de Neoplasias/genética , Genômica , Microambiente Tumoral/genética , Negro ou Afro-Americano/genética , Brancos/genética , Estados Unidos , Hispânico ou Latino/genéticaRESUMO
Cancer is a major public health issue that is associated with significant morbidity and mortality across the globe. At its root, cancer represents a genetic aberration, but socioeconomic, environmental, and geographic factors contribute to different cancer outcomes for selected population subsets. The disparities in the delivery of healthcare affect all aspects of cancer management from early prevention to end-of-life care. In an effort to address the inequality in the delivery of healthcare among socioeconomically disadvantaged populations, the World Health Organization defined social determinants of health (SDOH) as conditions in which people are born, live, work, and age. These factors play a significant role in the disproportionate cancer burden among different population groups. SDOH are associated with disparities in risk factor burden, screening modalities, diagnostic testing, treatment options, and quality of life of patients with cancer. The purpose of this article is to describe a more holistic and integrated approach to patients with cancer and address the disparities that are derived from their socioeconomic background.
Assuntos
Neoplasias , Qualidade de Vida , Humanos , Determinantes Sociais da Saúde , Morbidade , Organização Mundial da SaúdeRESUMO
Infections (including sepsis, meningitis, pneumonia and tetanus) stand as a major contributor to neonatal mortality in Haiti (22%). Infants acquire bacteria that cause neonatal sepsis directly from the mother's blood, skin or vaginal tract either before or during delivery. Nosocomial and environmental pathogens introduce further risk after delivery. The absence of cohesive medical systems and methods for collecting information limits the available data in countries such as Haiti. This study seeks to add more information on the burden of severe bacterial infections and their etiology in neonates of Haiti. Researchers conducted a secondary retrospective analysis of a de-identified database from the Neonatal Intensive Care Unit (NICU) at Nos Petit Frères et Soeurs-St. Damien Hospital (NPFS-SDH). Records from 1292 neonates admitted to the NICU at NPFS-SDH in Port-au-Prince Haiti from 2013 to 2015 were reviewed. Sepsis accounted for 708 of 1292 (54.8%) of all admissions to the NICU. Infants admitted for sepsis had a mortality rate of 23% (163 of 708 infants admitted for sepsis). The most common organism cultured was Streptococcus agalactiae, followed by Klebsiella pneumoniae, Pseudomonas aeroginusa, Enterobacter aerogenes, Staphylococcus aureus and Proteus mirabillis Failure to order or obtain a culture was associated with an increased fatality (odds ratio 2.4) for infants with sepsis. Resistance should be a concern when treating empirically.
Assuntos
Sepse/epidemiologia , Efeitos Psicossociais da Doença , Feminino , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/etiologia , Infecções por Bactérias Gram-Positivas/diagnóstico , Infecções por Bactérias Gram-Positivas/epidemiologia , Infecções por Bactérias Gram-Positivas/etiologia , Haiti/epidemiologia , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino , Estudos Retrospectivos , Fatores de Risco , Sepse/diagnóstico , Sepse/etiologiaRESUMO
Introduction: Efforts have been made to increase the number of women and physicians who are underrepresented in medicine (UIM). However, surgery has been slow to diversify, and there are limited data surrounding the impact of intersectionality. Objective: To assess the combined association of race and ethnicity and sex with rates of promotion and attrition among US academic medical department of surgery faculty. Design, Setting, and Participants: This was a retrospective cohort study using faculty roster data from the Association of American Medical Colleges. All full-time academic department of surgery faculty with an appointment any time from January 1, 2005, to December 31, 2020, were included. Study data were analyzed from September 2022 to February 2023. Exposures: Full-time academic faculty in a department of surgery with a documented self-reported race, ethnicity, and sex within the designated categories of the faculty roster of Association of American Medical Colleges. Main Outcomes and Measures: Trends in race and ethnicity and sex, rates of promotion, and rates attrition from 2010 to 2020 were assessed with Kaplan-Meier and Cox time-to-event analyses. Results: A total of 31â¯045 faculty members (23â¯092 male [74%]; 7953 female [26%]) from 138 institutions were included. The mean (SD) program percentage of UIM male faculty increased from 8.4% (5.5%) in 2010 to 8.5% (6.2%) in 2020 (P < .001), whereas UIM female faculty members increased from 2.3% (2.6%) to 3.3% (2.5%) over the 10-year period (P < .001). The mean program percentage of non-UIM females increased at every rank (percentage point increase per year from 2010 to 2020 in instructor: 1.1; 95% CI, 0.73-1.5; assistant professor: 1.1; 95% CI, 0.93-1.3; associate professor: 0.55; 95% CI, 0.49-0.61; professor: 0.50; 95% CI, 0.41-0.60; all P < .001). There was no change in the mean program percentage of UIM female instructors or full professors. The mean (SD) percentage of UIM female assistant and associate professors increased from 3.0% (4.1%) to 5.0% (4.0%) and 1.6% (3.2%) to 2.2% (3.4%), respectively (P =.002). There was no change in the mean program percentage of UIM male instructors, associate, or full professors. Compared with non-Hispanic White males, Hispanic females were 32% less likely to be promoted within 10 years (hazard ratio [HR], 0.68; 95% CI, 0.54-0.86; P <.001), non-Hispanic White females were 25% less likely (HR, 0.75; 95% CI, 0.71-0.78; P <.001), Hispanic males were 15% less likely (HR, 0.85; 95% CI, 0.76-0.96; P =.007), and Asian females were 12% less likely (HR, 0.88; 95% CI, 0.80-0.96; P =.03). Non-UIM males had the shortest median (IQR) time to promotion, whereas non-UIM females had the longest (6.9 [6.8-7.0] years vs 7.2 [7.0-7.6] years, respectively; P < .001). After 10 years, 79% of non-UIM males (13â¯202 of 16â¯299), 71% of non-UIM females (3784 of 5330), 68% of UIM males (1738 of 2538), and 63% of UIM females (625 of 999) remained on the faculty. UIM females had a higher risk of attrition compared with non-UIM females (HR, 1.3; 95% CI, 1.1-1.5; P = .001) and UIM males (HR, 1.2; 95% CI, 1.0-1.4; P = .05). The mean (SE) time to attrition was shortest for UIM females and longest for non-UIM males (8.2 [0.14] years vs 9.0 [0.02] years, respectively; P < .001). Conclusion and Relevance: Results of this cohort study suggest that intersectionality was associated with promotion and attrition, with UIM females least likely to be promoted and at highest risk for attrition. Further efforts to understand these vulnerabilities are essential.
Assuntos
Enquadramento Interseccional , Cirurgiões , Humanos , Masculino , Feminino , Estados Unidos , Estudos Retrospectivos , Estudos de Coortes , Mobilidade Ocupacional , Docentes de MedicinaRESUMO
PURPOSE: Obesity and weight gain in breast cancer survivors leads to a greater risk of recurrence and a decreased chance of survival. A paucity of data exists regarding strengths, weaknesses, and barriers for implementing culturally sensitive, patient-centered interventions for weight management among minority communities. The objective of this study was to evaluate breast cancer patients' experience and perspectives regarding weight management in a racially diverse population. METHODS: Semi-structured qualitative interviews were conducted with breast cancer patients with a body mass index ≥ 25 kg/m2 regarding their experience with weight management. Interviews were transcribed verbatim, and a thematic analysis was conducted. RESULTS: Participants (n = 17) most commonly self-identified as non-Hispanic Black (70.6%). Nearly all participants felt comfortable being approached about weight management, yet less than half (41.2%) reported that they knew about the link between breast cancer and body weight prior to the interview. Four themes emerged: (1) lack of knowledge regarding the link between body weight and breast cancer risk, (2) barriers to weight management including family stressors, high cost, mental health issues, and chronic medical conditions, (3) previous attempts at weight loss including bariatric surgery, and (4) best practices for approaching weight management including discussion of weight management prior to survivorship. CONCLUSION: There is a need for a multidisciplinary, patient-centered weight management program for minority breast cancer patients that improves awareness of the link between weight and breast cancer risk. Weight management should be introduced early on as an element of the treatment plan for breast cancer.
Assuntos
Neoplasias da Mama , Humanos , Feminino , Obesidade/psicologia , Redução de Peso , Índice de Massa Corporal , Grupos Minoritários , Pesquisa QualitativaRESUMO
BACKGROUND: Incisional hernia (IH) is a known complication after colorectal surgery. Despite advances in minimally invasive surgery, colorectal surgery still requires extraction sites for specimen retrieval, increasing the likelihood of postoperative IH development. The objective of this study is to determine the effect of specimen extraction site on the rate of IH after minimally invasive right-sided colectomy for patients with available imaging. STUDY DESIGN: This is a retrospective multi-institutional cohort study at 2 large academic medical centers in the US. Adults who underwent right-sided minimally invasive colectomy from 2012 to 2020 with abdominal imaging available at least 1 year postoperatively were included in the analysis. The primary exposure was specimen extraction via a midline specimen extraction vs Pfannenstiel specimen extraction. The main outcome was the development of IH at least 1 year postoperatively as visualized on a CT scan. RESULTS: Of the 341 patients sampled, 194 (57%) had midline specimen extraction and 147 (43%) had a Pfannenstiel specimen extraction. Midline extraction patients were older (66 ± 15 vs 58 ± 16; p < 0.001) and had a higher rate of previous abdominal operation (99, 51% vs 55, 37%, p = 0.01). The rate of IH was higher in midline extraction at 25% (48) compared with Pfannenstiel extraction (0, 0%; p < 0.001). The average length of stay was higher in the midline extraction group at 5.1 ± 2.5 compared with 3.4 ± 3.1 days in the Pfannenstiel extraction group (p < 0.001). Midline extraction was associated with IH development (odds ratio 24.6; 95% CI 1.89 to 319.44; p = 0.004). Extracorporeal anastomosis was associated with a higher IH rate (odds ratio 25.8; 95% CI 2.10 to 325.71; p = 0.002). CONCLUSIONS: Patients who undergo Pfannenstiel specimen extraction have a lower risk of IH development compared with those who undergo midline specimen extraction.
Assuntos
Colectomia , Hérnia Incisional , Humanos , Colectomia/efeitos adversos , Colectomia/métodos , Feminino , Masculino , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Hérnia Incisional/etiologia , Hérnia Incisional/epidemiologia , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Fatores de RiscoRESUMO
BACKGROUND: The availability and accuracy of data on a patient's race/ethnicity varies across databases. Discrepancies in data quality can negatively impact attempts to study health disparities. METHODS: We conducted a systematic review to organize information on the accuracy of race/ethnicity data stratified by database type and by specific race/ethnicity categories. RESULTS: The review included 43 studies. Disease registries showed consistently high levels of data completeness and accuracy. EHRs frequently showed incomplete and/or inaccurate data on the race/ethnicity of patients. Databases had high levels of accurate data for White and Black patients but relatively high levels of misclassification and incomplete data for Hispanic/Latinx patients. Asians, Pacific Islanders, and AI/ANs are the most misclassified. Systems-based interventions to increase self-reported data showed improvement in data quality. CONCLUSION: Data on race/ethnicity that is collected with the purpose of research and quality improvement appears most reliable. Data accuracy can vary by race/ethnicity status and better collection standards are needed.
Assuntos
Gerenciamento de Dados , Etnicidade , Grupos Raciais , Humanos , Asiático , Gerenciamento de Dados/organização & administração , Gerenciamento de Dados/normas , Gerenciamento de Dados/estatística & dados numéricos , Etnicidade/estatística & dados numéricos , Disparidades em Assistência à Saúde/etnologia , Disparidades em Assistência à Saúde/normas , Disparidades em Assistência à Saúde/estatística & dados numéricos , Hispânico ou Latino , Grupos Raciais/etnologia , Grupos Raciais/estatística & dados numéricos , Brancos , Negro ou Afro-Americano , População das Ilhas do Pacífico , Indígena Americano ou Nativo do AlascaRESUMO
INTRODUCTION: Disparities in surgical outcomes are well documented. Racial/ethnic minorities are also disproportionately underrepresentated in surgery; however, most surgeons do not acknowledge the existence of disparities. Diversity, equity, and inclusion (DEI) education in surgery is needed, yet DEI education is often confined to designated diversity lectures, limiting depth of content. Underrepresented minorities (URMs) are also more likely to be tasked with leading DEI initiatives, perpetuating the minority tax and limiting non-URM engagement. METHODS: A DEI curriculum was implemented in a general surgery department, inclusive of programming at morbidity and mortality (M&M) and grand rounds (GR). RESULTS/LESSONS LEARNED: After implementing a DEI curriculum there was a significant increase in DEI topics at M&M (0% versus 27.3%; p < 0.01) and GR (0% versus 18.4%; p < 0.001). The majority of DEI M&Ms were presented by non-URMs (88.89%). Most DEI GR were presented by URMs (55%). CONCLUSIONS: Structured integration of DEI initiatives into surgery department conferences may serve as a practical approach to increasing departmental awareness of disparities, expanding DEI engagement, and increasing academic recognition for DEI initiatives.
Assuntos
Internato e Residência , Grupos Minoritários , Etnicidade , HumanosRESUMO
Multiple Sclerosis is a chronic autoimmune neurodegenerative disorder of the central nervous system (CNS) that is characterized by inflammation, demyelination, and axonal injury leading to permeant disability. In the early stage of MS, inflammation is the primary driver of the disease progression. There remains an unmet need to develop high efficacy therapies with superior safety profiles to prevent the inflammation processes leading to disability. Herein, we describe the discovery of BIIB091, a structurally distinct orthosteric ATP competitive, reversible inhibitor that binds the BTK protein in a DFG-in confirmation designed to sequester Tyr-551, an important phosphorylation site on BTK, into an inactive conformation with excellent affinity. Preclinical studies demonstrated BIB091 to be a high potency molecule with good drug-like properties and a safety/tolerability profile suitable for clinical development as a highly selective, reversible BTKi for treating autoimmune diseases such as MS.
Assuntos
Tirosina Quinase da Agamaglobulinemia , Descoberta de Drogas , Esclerose Múltipla , Inibidores de Proteínas Quinases , Animais , Masculino , Ratos , Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Macaca fascicularis , Esclerose Múltipla/tratamento farmacológico , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/farmacologia , Ratos Sprague-Dawley , Distribuição TecidualRESUMO
This cohort study examines use of lumpectomy margin status in managing microcalcifications in breast cancer.
Assuntos
Neoplasias da Mama , Calcinose , Mamografia , Mastectomia Segmentar , Humanos , Neoplasias da Mama/cirurgia , Neoplasias da Mama/diagnóstico por imagem , Feminino , Calcinose/diagnóstico por imagem , Calcinose/cirurgia , Pessoa de Meia-IdadeRESUMO
Abnormalities in the X-linked FMR1 gene are associated with a constellation of disorders, which have broad and profound implications for the person first diagnosed, and extended family members of all ages. The rare and pleiotropic nature of the associated disorders, both common and not, place great burdens on (1) the affected families, (2) their care providers and clinicians, and (3) investigators striving to conduct research on the conditions. Fragile X syndrome, occurring more severely in males, is the leading genetic cause of intellectual disability. Fragile X associated tremor and ataxia syndrome (FXTAS) is a neurodegenerative disorder seen more often in older men. Fragile X associated primary ovarian insufficiency (FXPOI) is a chronic disorder characterized by oligo/amenorrhea and hypergonadotropic hypogonadism before age 40 years. There may be significant morbidity due to: (1) depression and anxiety related to the loss of reproductive hormones and infertility; (2) reduced bone mineral density; and (3) increased risk of cardiovascular disease related to estrogen deficiency. Here we report the case of a young woman who never established regular menses and yet experienced a 5-year diagnostic odyssey before establishing a diagnosis of FXPOI despite a known family history of fragile X syndrome and early menopause. Also, despite having clearly documented FXPOI the woman conceived spontaneously and delivered two healthy children. We review the pathophysiology and management of FXPOI. As a rare disease, the diagnosis of FXPOI presents special challenges. Connecting patients and community health providers with investigators who have the requisite knowledge and expertise about the FMR1 gene and FXPOI would facilitate both patient care and research. There is a need for an international natural history study on FXPOI. The effort should be coordinated by a global virtual center, which takes full advantage of mobile device communication systems.
RESUMO
Plethodontid salamanders are diverse and widely distributed taxa and play critical roles in ecosystem processes. Due to salamander use of structurally complex habitats, and because only a portion of a population is available for sampling, evaluation of sampling designs and estimators is critical to provide strong inference about Plethodontid ecology and responses to conservation and management activities. We conducted a simulation study to evaluate the effectiveness of multi-scale and hierarchical single-scale occupancy models in the context of a Before-After Control-Impact (BACI) experimental design with multiple levels of sampling. Also, we fit the hierarchical single-scale model to empirical data collected for Oregon slender and Ensatina salamanders across two years on 66 forest stands in the Cascade Range, Oregon, USA. All models were fit within a Bayesian framework. Estimator precision in both models improved with increasing numbers of primary and secondary sampling units, underscoring the potential gains accrued when adding secondary sampling units. Both models showed evidence of estimator bias at low detection probabilities and low sample sizes; this problem was particularly acute for the multi-scale model. Our results suggested that sufficient sample sizes at both the primary and secondary sampling levels could ameliorate this issue. Empirical data indicated Oregon slender salamander occupancy was associated strongly with the amount of coarse woody debris (posterior mean = 0.74; SD = 0.24); Ensatina occupancy was not associated with amount of coarse woody debris (posterior mean = -0.01; SD = 0.29). Our simulation results indicate that either model is suitable for use in an experimental study of Plethodontid salamanders provided that sample sizes are sufficiently large. However, hierarchical single-scale and multi-scale models describe different processes and estimate different parameters. As a result, we recommend careful consideration of study questions and objectives prior to sampling data and fitting models.