21 research outputs found
Moving Beyond Niche Models: Habitat Suitability for Nesting White-Headed Woodpeckers
Ecological niche models of habitat suitability are attractive due to their conceptual interpretation and use of presence-only data. Niche models have potential to exploit a variety of presence-only data sources, such as museum records, limited effort surveys, ancillary field observations, and citizen science programs. Limitations of niche models, however, substantially reduce their utility in management situations, in particular, the inability to independently evaluate habitat covariates for their relative influence. Generalized linear models, i.e., logistic regression, provide this ability, but require both presence and absence data. We present an approach that overcomes the limitation of niche models while retaining the use of presence-only data. The generation of pseudo-absences, derived from areas of low suitability as determined by the niche model, allow use of logistic regression to produce robust models of habitat suitability. The approach also has the added benefit of reducing contamination (false absences) among absence data that occurs with simple random sample approaches. We discuss the pseudo-absence approach in an example of modeling habitat suitability for nesting white-headed woodpeckers (Picoides albolarvatus)
Avian Community Response To A Recent Mountain Pine Beetle Epidemic
Recent epidemics of mountain pine beetles (Dendroctonus ponderosae) will fundamentally alter forests of the Intermountain West, impacting management decisions related to fire, logging, and wildlife habitat. We evaluated effects of a recent mountain pine beetle epidemic on site occupancy dynamics of > 60 avian species in four study units dominated by ponderosa pine (Pinus ponderosa) in the Helena National Forest. Point count data were collected during the avian breeding seasons (May-Jul) of 2003-2006 (pre-epidemic) and again during 2009-2010 (post-epidemic). We used a Bayesian hierarchical model that accounts for detection probability to obtain occupancy estimates for rare and elusive species as well as common ones. We estimated occupancy and detection for all species with respect to the occurrence of the beetle outbreak, live tree density at fine scale (1 ha), and live tree density at coarse (landscape) scale (100 ha). Preliminary analyses focus on trends in occupancy for species of interest, such as the American Three-toed Woodpecker (Picoides tridactylus), as well as patterns of occupancy for nesting and foraging guilds. Results indicated diverse responses among species, with occupancy rates increasing for some and declining for others
Impact of tertiary Gleason pattern 5 on prostate cancer aggressiveness: Lessons from a contemporary single institution radical prostatectomy series
Objective: To better evaluate tertiary Gleason pattern reporting and to evaluate the impact of tertiary Gleason pattern 5 (TP5) on prostate cancer pathological features and biochemical recurrence at our large single institution.
Methods: We retrospectively reviewed 1962 patients who underwent radical prostatectomy (RP) for prostate cancer; TP5 was reported in 159 cases (8.1%). Men with Gleason score (GS) 7 and GS 8 disease were divided into subgroups with and without TP5, and histopathological features were compared. Multivariate analyses were conducted to assess the impact on TP5 on biochemical-free survival (BFS).
Results: Tumors possessing GS 3 + 4 with TP5 were more likely to exhibit extraprostatic extension (EPE) and had a larger tumor diameter (TD) than GS 3 + 4 alone. GS 3 + 4 with TP5 was also associated with positive surgical margins (SM), seminal vesicle involvement (SVI), and higher pre-operative prostate-specific antigen (PSA) values, but without statistical significance. GS 4 + 3 with TP5 more commonly presented with EPE, positive SM, SVI, and greater TD and pre-operative PSA level than GS 4 + 3 alone. In multivariate analysis, Gleason score, EPE, and TP5 were overall independent risk factors for PSA recurrence in this cohort. Additionally, GS 4 + 3 with TP5 was associated with shorter time to recurrence versus GS 4 + 3 alone.
Conclusion: Our results emphasize the importance of TP5 and suggest that criteria for tertiary pattern reporting in prostate cancer should be standardized. Further studies are needed to evaluate the role of tertiary patterns in prognostic models
Independent surgical validation of the new prostate cancer grade‐grouping system
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134477/1/bju13488.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134477/2/bju13488_am.pd
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Systematic Review of Factors Associated with the Utilization of Radical Cystectomy for Bladder Cancer
ContextDespite established guidelines for the treatment of muscle-invasive bladder cancer, it has been reported that radical cystectomy (RC) is markedly underused, especially among patients of advanced age and those with higher comorbidity burden and lower access to care. Understanding the interactions between patient, provider, and hospital factors may inform targeted interventions to optimize RC utilization.ObjectiveTo systematically review the literature regarding factors associated with RC utilization.Evidence acquisitionA systematic search was conducted using Ovid and Medline according to Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines to identify studies between 1970 and 2017 reporting on RC utilization. Prospective and retrospective studies were included.Evidence synthesisThere are no published randomized control trials on RC utilization. Variations in study quality and design precluded a formal statistical meta-analysis. RC receipt significantly depended on patient, provider, and hospital factors. Patient factors associated with lower RC use included advanced age, African American and Hispanic race/ethnicity, higher comorbidity burden, unmarried marital status, higher tumor stage and grade, and lower socioeconomic status. Provider factors associated with underutilization included lower surgeon volume and a metropolitan location. Finally, hospital factors associated with lower RC use included low hospital volume, nonacademic affiliation, and hospital location in the Midwest.ConclusionsRC is reportedly underutilized. We found that age, race, marital status, socioeconomic factors, cancer severity, comorbidity burden, surgeon volume, and facility type and location significantly determined RC receipt. Improved understanding of the varying contributions of the risk factors according to patient, provider, and hospital determinants may assist in developing targeted interventions to improve RC utilization.Patient summaryIn this review we explored the clinical evidence for factors predicting the utilization of radical cystectomy for muscle-invasive bladder cancer. Many factors related to the patient, provider, and hospital determine whether patients receive this guideline-recommended treatment. However, there remains a lack of understanding on characterization and targeted interventions according to these levels, which may improve use
Recommended from our members
Systematic Review of Factors Associated with the Utilization of Radical Cystectomy for Bladder Cancer.
CONTEXT
Despite established guidelines for the treatment of muscle-invasive bladder cancer, it has been reported that radical cystectomy (RC) is markedly underused, especially among patients of advanced age and those with higher comorbidity burden and lower access to care. Understanding the interactions between patient, provider, and hospital factors may inform targeted interventions to optimize RC utilization.
OBJECTIVE
To systematically review the literature regarding factors associated with RC utilization.
EVIDENCE ACQUISITION
A systematic search was conducted using Ovid and Medline according to Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines to identify studies between 1970 and 2017 reporting on RC utilization. Prospective and retrospective studies were included.
EVIDENCE SYNTHESIS
There are no published randomized control trials on RC utilization. Variations in study quality and design precluded a formal statistical meta-analysis. RC receipt significantly depended on patient, provider, and hospital factors. Patient factors associated with lower RC use included advanced age, African American and Hispanic race/ethnicity, higher comorbidity burden, unmarried marital status, higher tumor stage and grade, and lower socioeconomic status. Provider factors associated with underutilization included lower surgeon volume and a metropolitan location. Finally, hospital factors associated with lower RC use included low hospital volume, nonacademic affiliation, and hospital location in the Midwest.
CONCLUSIONS
RC is reportedly underutilized. We found that age, race, marital status, socioeconomic factors, cancer severity, comorbidity burden, surgeon volume, and facility type and location significantly determined RC receipt. Improved understanding of the varying contributions of the risk factors according to patient, provider, and hospital determinants may assist in developing targeted interventions to improve RC utilization.
PATIENT SUMMARY
In this review we explored the clinical evidence for factors predicting the utilization of radical cystectomy for muscle-invasive bladder cancer. Many factors related to the patient, provider, and hospital determine whether patients receive this guideline-recommended treatment. However, there remains a lack of understanding on characterization and targeted interventions according to these levels, which may improve use