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Biomedical subjects

Michael H Johnson

Publications and source records attributed to Michael H Johnson.

5 recordsLinked to original sources
PubMed2006

Geographical variation in surveillance strategies after curative-intent surgery for upper aerodigestive tract cancer.

BACKGROUND: Analysis of geographical variation in utilization of medical resources is often used to identify regions of overutilization or underutilization. METHODS: We surveyed the membership of the American Head and Neck Society regarding their recommended frequency of office visits and 13 imaging studies and blood tests for their patients after potentially curative therapy for upper aerodigestive tract cancers. RESULTS: Of the 1322 members surveyed, 610 (46%) responded: 420 responses (32%) were assessable. Responses were compared by US Census Region, Metropolitan Statistical Area, and managed care organization penetration rate. Overseas members (16% of assessable responses) comprised a separate category for the regional analysis. There were statistically significant variations in practice patterns among Census Regions for office visits, complete blood count, computed tomography of the head, sonography, and esophagoscopy. Non-US members recommended significantly more blood tests, imaging studies, and endoscopy than US members for routine cancer surveillance. Only the frequency of office visits differed significantly among Metropolitan Statistical Areas. Surprisingly, the penetration rate of managed care organizations had no significant effect on posttreatment surveillance intensity. CONCLUSIONS: This analysis indicates that only a small portion of the wide variation in observed follow-up practice patterns can be explained by geographical determinants.

Analysis of Variance↗
PubMed2006

SBEAMS-Microarray: database software supporting genomic expression analyses for systems biology.

BACKGROUND: The biological information in genomic expression data can be understood, and computationally extracted, in the context of systems of interacting molecules. The automation of this information extraction requires high throughput management and analysis of genomic expression data, and integration of these data with other data types. RESULTS: SBEAMS-Microarray, a module of the open-source Systems Biology Experiment Analysis Management System (SBEAMS), enables MIAME-compliant storage, management, analysis, and integration of high-throughput genomic expression data. It is interoperable with the Cytoscape network integration, visualization, analysis, and modeling software platform. CONCLUSION: SBEAMS-Microarray provides end-to-end support for genomic expression analyses for network-based systems biology research.

Chromosome Mapping↗
PubMed2006

Development of the Minimum Information Specification for In Situ Hybridization and Immunohistochemistry Experiments (MISFISHIE).

We describe the creation process of the Minimum Information Specification for In Situ Hybridization and Immunohistochemistry Experiments (MISFISHIE). Modeled after the existing minimum information specification for microarray data, we created a new specification for gene expression localization experiments, initially to facilitate data sharing within a consortium. After successful use within the consortium, the specification was circulated to members of the wider biomedical research community for comment and refinement. After a period of acquiring many new suggested requirements, it was necessary to enter a final phase of excluding those requirements that were deemed inappropriate as a minimum requirement for all experiments. The full specification will soon be published as a version 1.0 proposal to the community, upon which a more full discussion must take place so that the final specification may be achieved with the involvement of the whole community.

Computational Biology↗
PubMed2002

Surgical decision making in upper aerodigestive tract cancer patient follow-up.

The objective was to analyze the impact of clinical beliefs on surgical decision making in the posttreatment follow-up of patients with upper aerodigestive tract cancer. Clinical beliefs, defined as perceived benefits and risks of surveillance, were examined. All 824 members of the Society of Head and Neck Surgeons (SHNS) and 522 members of the American Society for Head and Neck Surgery, who were not SHNS members, were surveyed using TNM stage-specific clinical vignettes to measure surgical decision making in the posttreatment follow-up of patients with upper aerodigestive tract cancer. Controlling for physician demographic and practice characteristics, the relationship between clinical beliefs and diagnostic test ordering practices of surgeons was examined using Poisson and negative binomial regression analysis. Age 50 and over and South Central U.S. practice location were significant predictors of the frequency of surveillance testing in at least three TNM stage I models as was the clinical belief that no survival benefit results from the follow-up of patients with TNM stage I cancers. Less than 15% of the variability in follow-up intensity was explained by the TNM stage I models. Predictive ability was substantially improved for the TNM stage II-IV models by including lower TNM stage practice patterns as an independent variable. Most models predicted at least 50% of the variation in follow-up testing. The two clinical beliefs with the greatest impact on surgical decision making in the posttreatment follow-up of patients with upper aerodigestive tract cancer are that surveillance: i) permits palliative treatment and improves quality of life and ii) provides no survival benefit for patients with TNM stage I cancers. Knowledge of lower TNM stage practice patterns can be used to further improve predictive ability for higher stage models.

Adult↗