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PubMed1984

BCG prophylaxis against cancer: methodological evaluation of a continuing controversy.

A possible protective effect of tuberculosis against cancer, together with the known immune-stimulating properties of BCG, have motivated 14 investigations of BCG prophylaxis against cancer. The results have been conflicting: 3 studies found high levels of protection, 8 found no effect, and 3 suggested that BCG may actually raise the risk of cancer. To assess whether the inconsistent results could have a methodological basis, we analyzed each study according to several basic criteria necessary for scientific validity in cause-effect research. The analyses showed two major problems: (1) None of the studies used safeguards against detection bias by ensuring that the diagnosis of cancer in vaccinees and non-vaccinees was made with equal follow-up and surveillance procedures, and in an accurate and unbiased fashion; (2) Studies alleging that BCG is carcinogenic were weakened by the inappropriate use of cancer mortality data, by the analysis of multiple BCG-cancer associations without appropriate statistical adjustment, and by post hoc creation of new cancer risk categories after inspection of the data. Since these methodologic inadequacies preclude any firm conclusions about the role of BCG in preventing cancer, a resolution of the controversy will require new research, designed and conducted with greater attention to methodologic principles necessary to ensure scientific validity.

BCG Vaccine↗

PubMed1992

Methodological problems in investigating disease clusters.

Increased reporting of disease clusters is stretching health department resources while failing to uncover many significant environmental hazards. By reviewing the methodology by which health departments respond to such reports, we argue that there is a strong bias against investigating the most hazardous situations. Failure to find serious hazards is more a reflection of the methodology used than an assessment of the existence of environmental problems. The biases arise from the selection of situations that dictate full in-house consideration, the selection of the methodology used to evaluate reported or registry-based data, and the interpretation given to anomalous observations. We argue for more rigorous evaluation of statistical cluster detection methods and for use of more objective criteria in cluster investigation protocols.

Disease Outbreaks↗

PubMed1988

Radioligand competitive binding methodology for the evaluation of platelet-activating factor (PAF) and PAF-receptor antagonism using intact canine platelets.

High-affinity, stereoselective, and ligand-selective specific binding of 3H-labeled platelet-activating factor (PAF) to its receptor on the dog platelet is reproducible over wide mass and concentration ranges of [3H]PAF. The [3H]PAF specific binding can be competitively inhibited by low picogram amounts of nonlabeled PAF. These observations have led to the formulation of radioligand competitive binding methodology for the detection and estimation of PAF in a biological lipid sample and the quantitative evaluation of PAF-receptor antagonism. The methodology is predicated upon correlation between the ability of a PAF analog/biological lipid sample/(synthetic) substance to inhibit [3H]PAF specific binding to the washed canine platelet and the known inhibition of [3H]PAF specific binding by standard, nonradioactive PAF. Application of this methodology to lipid extracts of human saliva has uncovered the finding that subjects with upper respiratory infection and chronic allergies have high saliva PAF contents. Pharmacologically active antiallergy agents known to inhibit PAF-induced pathology in animal models of disease were demonstrated, with the methology advanced, to act as PAF-receptor antagonists, and their potencies were quantified. These investigations indicate that the system proposed, in its ease, economy, sensitivity, specificity and capacity, has practical value for detecting and estimating PAF in biological lipid extracts and for evaluating PAF-receptor antagonism.

Animals↗

PubMed1996

Psychobiologic effects of 3,4-methylenedioxymethamphetamine in humans: methodological considerations and preliminary observations.

3,4-Methylenedioxymethamphetamine (MDMA) is a phenethylamine with potent effects on serotonergic neurotransmission which has been the object of controversy over its potential as a therapeutic adjunct versus its possible risks for causing neurotoxic injury. This paper discusses the background, methodology and preliminary findings of the first FDA approved Phase I study prospectively evaluating the effects of MDMA administration in humans. Six subjects with prior experience with MDMA were administered two different dosages of MDMA and an inactive placebo utilizing a randomized, double-blind methodologic design. Dosages from 0.25 to 1.0 mg/kg, p.o., were administered. All subjects tolerated the procedures without any overt evidence of physical discomfort or psychological distress. MDMA produced a modest increase in heart rate and blood pressure. The threshold dose for the stimulation of ACTH and prolactin appeared to be between 0.5 and 0.75 mg/kg, with the two higher doses clearly stimulating both ACTH and prolactin. Methodology for assessing MDMA's effects on serotonergic neurotransmission is discussed.

Adult↗

PubMedDate not supplied

The shine methodology--identifying telematic service opportunities for healthcare.

The SHINE methodology has been developed to analyse the business needs of healthcare providers. It forms part of an overall SHINE framework that offers complete support from the development of an information technology strategy through to evaluating the implementation of telematic services. The five stages of the methodology are described together with its position in the overall framework. An example is presented showing the impact of applying the methodology to the entitlement assessment of medical cards and compares this approach with a more conventional approach.

Commerce↗

PubMed1995

The development of a new methodology to assess perceived needs among indigenous Australians.

The present study examined a new methodology to assess the perceived needs of Indigenous Australians in two urban communities. This methodology, utilizing graphics, allowed for the classification of general areas of need into four domains namely, health, education and employment, housing as well as social issues and community facilities. In addition participants were able to prioritize their identified needs both within the four domains as well as across domains. Overall, a number of similarities of perceived needs were noted between the communities. The results are discussed in terms of the lack of information on Indigenous Australian peoples' perceptions of their needs and the use of the new methodology to allow a wider examination of perceived needs.

Adolescent↗

PubMed1987

Alcohol treatment outcome evaluation methodology: state of the art 1980-1984.

The methodology of alcohol treatment outcome studies published during two sequential intervals from 1976 through mid-1984 is critically reviewed. Although considerable methodological improvements have occurred over time, major methodological deficiencies continue to characterize much of the literature, with inadequate reporting of subjects' pretreatment characteristics (e.g., severity of dependence) being the most striking problem. Pervasive differences across studies regarding the types of data gathered and the ways in which findings are reported seriously impede attempts to compare studies and weaken the types of conclusions that can be drawn about treatment efficacy in general. It is suggested that journal editors establish standards of reporting for follow-up studies.

Alcoholism↗

PubMed2006

Search and selection methodology of systematic reviews in orthodontics (2000-2004).

INTRODUCTION: More systematic reviews related to orthodontic topics are published each year, although little has been done to evaluate their search and selection methodologies. METHODS: Systematic reviews related to orthodontics published between January 1, 2000, and December 31, 2004, were searched for their use of multiple electronic databases and secondary searches. The search and selection methods of identified systematic reviews were evaluated against the Cochrane Handbook's guidelines. RESULTS: Sixteen orthodontic systematic reviews were identified in this period. The percentage of reviews documenting and using each criterion of article searching has changed over the last 5 years, with no recognizable directional trend. On average, most systematic reviews documented their electronic search terms (88%) and inclusion-exclusion criteria (100%), and used secondary searching (75%). Many still failed to search more than MEDLINE (56%), failed to document the database names and search dates (37%), failed to document the search strategy (62%), did not use several reviewers for selecting studies (75%), and did not include all languages (81%). CONCLUSIONS: The methodology of systematic reviews in orthodontics is still limited, with key methodological components frequently absent or not appropriately described.

Databases, Bibliographic↗

PubMed2005

Human error risk management methodology for safety audit of a large railway organisation.

This paper considers the application of the human error risk management for engineering systems (HERMES) methodology for safety assessment studies. The application concerns the recurrent safety audits (RSA) of a large organisation in the domain of railway transportation systems. The objective of the study was the identification of the most relevant areas of intervention for improving safety and reliability of the service. The methodology has been applied to the whole organisation and its working processes. Specific attention was paid to train drivers. A number of critical indicators of safety and recurrent safety audit matrices were identified, which enabled the assessment of the safety level of the organisation and the generation of safety recommendations. The application of HERMES to this case study shows that the methodology is applicable in practice and can give valuable and significant results.

Efficiency, Organizational↗

PubMed2005

Design and validation of a methodology using the International Classification of Diseases, 9th Revision, to identify secondary conditions in people with disabilities.

OBJECTIVE: To design and validate a methodology that identifies secondary conditions using International Classification of Disease, 9th Revision (ICD-9) codes. DESIGN: Secondary conditions were identified through a literature search and a survey of Washington State physiatrists. These conditions were translated into ICD-9 codes and this list was then validated against a national sample of Medicare survey respondents with differing levels of mobility and activities of daily living (ADL) disability. SETTING: National survey. PARTICIPANTS: Participants (N=9731) in the 1999 Medicare Current Beneficiary Survey with no, mild, moderate, and severe mobility and ADL disability. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Percentage of survey respondents with a secondary condition. The secondary conditions were grouped into 4 categories: medical, psychosocial, musculoskeletal, and dysphagia related (problems associated with difficulty in swallowing). RESULTS: Our literature search and survey of 26 physiatrists identified 64 secondary conditions, including depression, decubitus ulcers, and deconditioning. Overall, 70.4% of all survey respondents were treated for a secondary condition. We found a significant relation between increasing mobility as well as ADL disability and increasing numbers of secondary conditions (chi 2 test for trend, P <.001). This relation existed for all categories of secondary conditions: medical (chi 2 test for trend, P <.001), psychosocial (chi 2 test for trend, P <.001), musculoskeletal (chi 2 test for trend, P <.001), and dysphagia related (chi 2 test for trend, P <.001). CONCLUSIONS: We created a valid ICD-9-based methodology that identified secondary conditions in Medicare survey respondents and discriminated between people with different degrees of disability. This methodology will be useful for health services researchers who study the frequency and impact of secondary conditions.

Disability Evaluation↗

PubMed2005

CNS injury research; reviewing the last decade: methodological errors and a proposal for a new strategy.

During the last decades the field of Traumatic Brain Injury (TBI) has been characterized by a paucity of new treatments. This is in contrast to the amount of pre-clinical experimental work and the number of clinical trials done. This paper aims to contribute to the ongoing debate on the reasons that have led to this phenomenon. A reasonable suggestion could be the presence of methodological limitations when comparing and integrating experimental results. The first methodological drawback, which is shortly discussed, is the insistence (during the last decades) on the concept of "similarity to the human pathology" as the main criterion to evaluate results, and the constant effort to create a "super model" that would fully replicate human TBI cases. The second methodological limitation examined is the lack of a common way to present and analyze data. It is proposed that the basic neuro-histo-pathology of each injury model should serve as the ground on which hypotheses should be built, as it could constitute the common basis for comparisons between different experimental settings. In this context, 95 papers reporting experimental results from various models of animal CNS injury were reviewed in order to examine the extent to which results were presented and analyzed using a common basis. No such common basis was observed; moreover, the review revealed a remarkable lack of histopathological examination of the animals, especially when biochemical and/or behavioral endpoints were assessed. It is argued that this practice deprives data of an objective common basis. Conclusively, a new theoretical way of organizing experimental work in the field of TBI is briefly presented.

Animals↗

PubMed2005

Prescript-Assist probiotic-prebiotic treatment for irritable bowel syndrome: a methodologically oriented, 2-week, randomized, placebo-controlled, double-blind clinical study.

BACKGROUND: The symptomatic efficacy of Prescript-Assist (Safer Medical, Inc., Fort Benton, Montana), a treatment combining probiotic and prebiotic components, has previously been evaluated clinically only in an open-label study in patients with various gastrointestinal conditions, including irritable bowel syndrome (IBS). OBJECTIVES: This study was conducted primarily to compare the effects of Prescript-Assist with placebo in patients with a diagnosis of IBS. Toward this objective, a secondary methodologic goal was to determine the number and nature of symptom clusters ("subsyndromic factors") that characterize IBS. METHODS: This was a double-blind, placebo-controlled clinical study in which patients were randomly assigned to receive either Prescript-Assist one 500-mg capsule BID or 1 placebo capsule BID for 2 weeks. Thirteen IBS symptoms identified from the clinical literature were embedded in a larger research instrument. Using a scale from 0 to 5, patients rated the intensity of these symptoms for the 7-day period immediately before the start of treatment, at the end of each study week, and after each of the 2 subsequent weeks (during which all patients received open-label Prescript-Assist as part of a larger study evaluating methodologic approaches to enhancing assessments of medication efficacy/safety). The symptom-intensity data were subjected to maximum likelihood factor analysis with varimax rotation to identify any IBS subsyndromic factors, and the effect of treatment on each of the identified factors was evaluated using analyses of covariance with appropriate baseline-week assessments as covariate controls. RESULTS: The study included 25 patients with IBS (23 women, 2 men; age range, 20-70 years). Three subsyndromic factors were identified that together accounted for 60.2% of total IBS symptom variance: factor 1, general ill feelings/nausea; factor 2, indigestion/flatulence; and factor 3, colitis. Treatment with Prescript-Assist was associated with significant reductions in each of the subsyndromic factors. Factor 1 was significantly reduced by 0.345 standard score units (F(1,46) = 4.26; P = 0.042), factor 2 by 0.544 standard score units (F(1,46) = 7.83; P = 0.008), and factor 3 by 0.826 standard score units (F(1,46) = 10.20; P = 0.003). CONCLUSIONS: This study identified 3 subsyndromic factors of IBS: general ill feelings/nausea, indigestion/flatulence, and colitis. In this methodologically oriented double-blind study in patients with IBS, combined probiotic-prebiotic treatment with Prescript-Assist was associated with significant reductions in these factors.

Administration, Oral↗

PubMed2006

Keeping the pieces together: comparison of mass grave excavation methodology.

Mass graves are a complex and confusing mix of bodies, body parts, soils, artifacts, and other feature evidence. Forensic investigations of these complex crime scenes should attempt to maximize the collection of evidence, which includes the mortal remains, in their best possible condition as they were deposited within the graves. Two standard methods of mass grave excavation were examined with the aim of identifying the better approach. Two experienced teams using different methodologies excavated two separate but very comparable mass graves located in the same area. Single disarticulated skeletal elements not associated with a body at the time of removal from the grave were categorized and their counts analyzed to evaluate the efficiency of the differing excavation methodologies. The methodologies used were the 'pedestal' method, which focuses on the body mass, and the 'stratigraphic' method, in which the grave feature and contents are conjointly excavated. The first grave (Grave A), excavated using the 'pedestal' method, was observed to have a disproportionately larger amount of unassociated bones than did the second (Grave B), which used the 'stratigraphic' method. Chi-square (chi2) goodness-of-fit and contingency tests were performed on the total numbers of recorded elements and different categorical groups of bones, based on size and shape, in each grave. Results demonstrate that significantly greater numbers of unassociated elements resulted from the excavation of Grave A using the pedestal method, both in total number of disarticulated bones as well as within 'large' and 'medium' categories. Conversely 'small' skeletal elements were recovered at a higher rate in Grave B. The lower 'large' and 'medium' bone production rates from Grave B indicate that the stratigraphic method better maintained the provenience and articulation of remains than did Grave A, while the higher 'small' bone recovery rate may point to better recovery techniques of Grave B's excavation team.

Archaeology↗

PubMed2004

Analysis of dose conformity and normal-tissue sparing using two different IMRT prescription methodologies for irregularly shaped CNS lesions irradiated with the Beak and 1-cm MIMiC collimators.

PURPOSE: To determine whether intensity modulated sequential tomotherapy using the NOMOS Beak provides superior dose conformity and organ sparing to the MIMiC "1-cm" mode, and if so, to identify a subset of patients most likely to benefit from Beak intensity modulated sequential tomotherapy. METHODS AND MATERIALS: Twelve patients with irregularly shaped central nervous system tumors were selected for intensity modulated radiation therapy planning. Two treatment plans, one using the Beak collimator and the other using the 1-cm MIMiC collimator, were generated for each patient with identical anatomic contouring, prescriptions, and optimization algorithms. The Beak attaches to the MIMiC collimator and truncates the 1-cm MIMiC mode beamlet size from 1.00 x 0.85 cm(2) to 1.00 x 0.39 cm(2) at isocenter. Conformity indexes were calculated for each lesion using two different prescription methodologies, and mean doses to critical structures were recorded. RESULTS: For the first prescription methodology using uniform prescribed isodose, mean conformity index was 2.19 (range, 1.33-3.90) for the Beak compared to 2.67 (range, 1.64-4.75) for the 1-cm mode (p = 0.0003). Mean doses to the brainstem, right orbit, and left optic nerve were significantly lower with the Beak than with the 1-cm mode (p = 0.0150, 0.0068, and 0.0284, respectively). For the second prescription methodology using uniform target volume coverage prescription, mean conformity index was 2.04 (range, 1.56-2.70) for the Beak compared to 2.73 (range, 1.70-8.58) for the 1-cm mode (p = 0.07). Mean doses to the brain, brainstem, optic chiasm, right optic nerve, left optic nerve, and left orbit were significantly lower with the Beak than with the 1-cm mode (p = <0.0001, <0.0026, <0.0016, <0.0076, <0.0007, and <0.046, respectively). CONCLUSION: Beak intensity modulated sequential tomotherapy is superior to the 1-cm MIMiC mode for irregularly shaped central nervous system tumors, because it provides better conformity and critical organ sparing. These differences may allow for safer dose escalation and retreatment, so the method presents an alternative to gamma knife stereotactic radiosurgery.

Algorithms↗

PubMed2006

Analytical methodologies for the detection and structural characterization of phosphorylated proteins.

Phosphorylation of proteins is a frequent post-translational modification affecting a great number of fundamental cellular functions in living organisms. Because of its key role in many biological processes, much effort has been spent over the time on the development of analytical methodologies for characterizing phosphoproteins. In the past decade, mass spectrometry-based techniques have emerged as a viable alternative to more traditional methods of phosphorylation analysis, providing accurate information for a purified protein on the number of the occurring phosphate groups and their exact localization on the polypeptide sequence. This review summarizes the analytical methodologies currently available for the analysis of protein phosphorylation, emphasizing novel mass spectrometry (MS) technologies and dedicated biochemical procedures that have been recently introduced in this field. A formidable armamentarium is now available for selective enrichment, exaustive structural characterization and quantitative determination of the modification degree for phosphopeptides/phosphoproteins. These methodologies are now successfully applied to the global analysis of cellular proteome repertoire according a holistic approach, allowing the quantitative study of phosphoproteomes on a dynamic time-course basis. The enormous complexity of the protein phosphorylation pattern inside the cell and its dynamic modification will grant important challenges to future scientists, contributing significantly to deeper insights into cellular processes and cell regulation.

Electrophoresis, Gel, Two-Dimensional↗

PubMed2004

Medical researchers evaluate their methodological skills.

BACKGROUND AND OBJECTIVE: Clinical epidemiology and statistics skills of clinical researchers are often limited. We assessed methodological skills of medical researchers and identified factors associated with higher skill levels. METHODS: In a cross-sectional mail survey at two Swiss teaching hospitals, participants (N=409) rated their ability to perform 26 research-related activities, such as identifying the research question, selecting a study design, computing the required sample size, performing data analysis, and reporting results. RESULTS: The proportion of respondents who were able to perform a specific activity was 33.2% on average, ranging from 1.5% for "numerical statistics (bootstrap, simulation, cross-validation,...)" to 76.0% for "oral presentation of results." The overall skill level (expressed as a percentage of the 26 activities) was associated with principal investigator experience (+8.7%), greater percentage of time devoted to research (+12.4% for near full-time versus no time commitment), years of research experience (+17.6% for 15-40 years versus 0 years), past number of clinical research projects (+18.0% for 15-230 projects versus 0-1 projects), and hours of formal methodological training (+32.6% for 200-1200 hours versus 0-9 hours). CONCLUSION: Self-reported methodological skills were generally modest. The most important covariates of skill levels were current time commitment to research, past experience, and formal training.

Adult↗

PubMed2006

Methodological shortcomings predicted lower harm estimates in one of two sets of studies of clinical interventions.

OBJECTIVES: High quality harms data are necessary to appropriately assess the balance between benefits and harms of interventions. Little is known, however, about whether perceived methodological shortcomings are associated with lower estimates of harms. STUDY DESIGN AND SETTING: Studies reporting harms associated with carotid endarterectomy (CEA) and rofecoxib were identified using published systematic reviews. A standardized abstraction form, including eight predefined criteria for assessing the quality of harms reporting, was used to extract data. Univariate and multivariate analyses were performed to empirically evaluate the association between quality criteria and estimates of harms. RESULTS: In 111 studies of CEA, meeting five of the eight-quality criteria was associated with significantly higher adverse event rates. A quality-rating instrument with four criteria predicted adverse events (5.7% in studies rated "adequate," compared to 3.9% in studies rated "inadequate" [P=0.0003]). In multivariate analyses, the quality-rating assignment remained significant when controlling for other clinical and study-related variables. Different quality criteria, however, predicted estimates of risk for myocardial infarction in 16 trials of rofecoxib. CONCLUSION: The presence of methodological shortcomings can predict lower estimates of serious harms. Clinicians and researchers should consider methodological shortcomings when evaluating estimates of harms associated with clinical interventions.

Biomedical Research↗

PubMed2006

Methodological quality of patient-reported outcome research was low in complementary and alternative medicine in oncology.

OBJECTIVE: To evaluate the methodological robustness of patient-reported outcomes (PROs) evaluation in complementary and alternative medicine (CAM) randomized controlled trials (RCTs) in oncology. STUDY DESIGN AND SETTING: CAM RCTs with a PRO endpoint were retrieved from a number of electronic databases. CAM interventions were defined according to the five major categories of the National Center for Complementary and Alternative Medicine. The "Minimum Standard Checklist for Evaluating HRQOL Outcomes in Cancer Clinical Trials" was used to assess the quality of the PRO reporting in these trials. RESULTS: Forty-four RCTs enrolling 4,912 patients were identified: six studies involved alternative medical systems, 14 involved mind body interventions, 15 dealt with biologically-based therapies, seven involved manipulative and body-based methods, and two energy therapies. Eighty-nine percent of studies used a PRO as a primary endpoint and 59% documented PRO missing data. Although 84% of the studies used a validated PRO questionnaire, only 37% stated an a priori hypothesis and 20% addressed clinical significance of the outcomes. Overall, 64% of the studies analyzed exhibited a number of methodological drawbacks. CONCLUSIONS: To facilitate the interpretation of results from such CAM RCTs, investigators are encouraged to pay greater attention to key methodological issues as identified in this study.

Complementary Therapies↗