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PubMed2006

New methodology and instrumentation for follicular unit extraction: lower follicle transection rates and expanded patient candidacy.

BACKGROUND: Follicular unit extraction (FUE), as described in the literature for harvesting follicular units, is technically demanding, has limited patient candidacy, and can potentially result in high rates of follicle transection. Although FUE has potential advantages, such as faster surgical recovery, less postoperative pain, less noticeable scarring, and possible expansion of the donor area, the acceptance of the technique is limited by the problems noted above. The proposed methodology and instrumentation may allow widespread adoption of FUE. OBJECTIVE: To present the SAFE (Surgically Advanced Follicular Extraction) System, a new methodology and novel instrumentation for FUE. This article presents the efficacy of this methodology and addresses patient candidacy. METHODS: Twenty-two patients undergoing standard strip excision were enrolled in a pilot study to assess follicle transection rates using the SAFE System. Based on the success of the pilot study, an additional 37 patients receiving a total of 6,947 grafts were examined. Transection rates were recorded, and patients were examined for complications or adverse reactions. RESULTS: The average follicle transection rate was 6.14%, with a range of 1.7 to 15%. The only adverse reaction was the occurrence of two buried grafts, resulting in inflammatory subcutaneous cysts requiring excision. CONCLUSION: It appears that the SAFE System provides the methodology and instrumentation to enhance current FUE techniques and expand patient candidacy. The transection rate of this method compares favorably with traditional microscope graft dissection. Physicians with a modicum of technical skills can use the technique, and there does not appear to be a significant adverse reaction rate.

Equipment Design↗

PubMed2004

Bounding analysis as an inadequately specified methodology.

The bounding analysis methodology described by Ha-Duong et al. (this issue) is logically incomplete and invites serious misuse and misinterpretation, as their own example and interpretation illustrate. A key issue is the extent to which these problems are inherent in their methodology, and resolvable by a logically complete assessment (such as Monte Carlo or Bayesian risk assessment), as opposed to being general problems in any risk-assessment methodology. I here attempt to apportion the problems between those inherent in the proposed bounding analysis and those that are more general, such as reliance on questionable expert elicitations. I conclude that the specific methodology of Ha-Duong et al. suffers from logical gaps in the definition and construction of inputs, and hence should not be used in the form proposed. Furthermore, the labor required to do a sound bounding analysis is great enough so that one may as well skip that analysis and carry out a more logically complete probabilistic analysis, one that will better inform the consumer of the appropriate level uncertainty. If analysts insist on carrying out a bounding analysis in place of more thorough assessments, extensive analyses of sensitivity to inputs and assumptions will be essential to display uncertainties, arguably more essential than it would be in full probabilistic analyses.

Comment↗

PubMed1985

OARS methodology. A decade of experience in geriatric assessment.

The Older Americans Resources and Services (OARS) methodology was designed to assess functional capacity in five dimensions (social resources, economic resources, mental health, physical health, and activities of daily living) and to measure use of and need for 24 types of generic services. The OARS questionnaire now has been used in more than 150 research and practice settings. Recent refinements in the OARS methodology include new information about validity and reliability, computerized summary ratings for the five dimensions of functional status, and eleven scales that measure specific aspects of functioning within the five dimensions. This paper describes the conceptual foundation, appropriate uses, psychometric properties, and recent refinements in the OARS methodology. Empirical data from a geriatric clinic population are used for purposes of illustration. The paper presents an assessment of the strengths and limitations of the OARS methodology based on more than a decade of experience. Particular attention is paid to the degree to which the measures of functional status can be related to health service use measures to inform geriatric research and practice.

Activities of Daily Living↗

PubMed1997

Derivation and validation of a methodology for tracking academic stature of medical schools. Task Force on the Development of Emergency Medicine.

OBJECTIVE: To derive and validate a methodology for academic ranking of allopathic medical schools in order to track the development of emergency medicine (EM) at academic medical centers. METHODS: A methodology for institutional ranking according to NIH research grant funding was derived by using a well-known multiaxial ordinal ranking of all Liaison Committee on Medical Education (LCME)-accredited allopathic schools in 1990-91 as the criterion standard. This methodology was validated against the same annually updated criterion standard in 1995-96. Both ranking schemes were first stratified by quartile, then aggregated pairwise by contiguous quartiles to develop a 3 x 3 concordance matrix. RESULTS: Ranking by NIH grant funding produced concordance between all 126 schools in the derivation set and 123/124 schools in the validation set. CONCLUSION: NIH research grant funding may be used as a valid methodology for broad categorization of allopathic medical school academic rank. This strategy should therefore serve as a suitable means of following the development of academic EM over time.

Databases, Factual↗

PubMed1990

One year's experience of major trauma outcome study methodology.

OBJECTIVE: To assess the feasibility and the validity of an audit using major trauma outcome study methods in an accident and emergency department. DESIGN: Prospective audit of all cases of trauma in patients admitted to a hospital from an accident and emergency department. SETTING: Accident and emergency department in a teaching hospital. PATIENTS: 1577 Patients admitted with trauma, of whom 695 met the inclusion criteria for the study--that is, were admitted for more than three days, or admitted to intensive care, or died. 17 Patients were excluded because of failure to trace their notes. OUTCOME MEASURES: Review of case notes with TRISS (trauma score, injury severity score) methodology to compare expected and observed survival. RESULTS: Most (421/678) admissions were due to single orthopaedic injury. Serious injury was uncommon with only 43 patients having injury severity scores greater than 15. The calculated probability of survival matched the observed outcome for most of the seriously injured patients, with only two unexpected deaths. However, 36 of the 61 deaths in the 678 patients occurred in elderly patients with a fractured neck of the femur, and all of these patients had a high probability of survival predicted by TRISS methodology. CONCLUSIONS: Application of TRISS methodology seems to be valid for seriously injured patients except for elderly patients with single orthopaedic injuries, in whom there were major differences between observed and expected outcomes. Using outcome norms from the United States may not be applicable for this group. IMPLICATIONS: Audit of management of major injuries should be carried out by every hospital, and the methodology of the major trauma outcome study is an excellent system for carrying out such audit. The study of all patients admitted with trauma requires appreciable extra resources, but most hospitals should be able to monitor the care of seriously injured patients as their numbers are much fewer.

Adolescent↗

PubMed2005

Assessment of methodological quality of primary studies by systematic reviews: results of the metaquality cross sectional study.

OBJECTIVES: To describe how the methodological quality of primary studies is assessed in systematic reviews and whether the quality assessment is taken into account in the interpretation of results. DATA SOURCES: Cochrane systematic reviews and systematic reviews in paper based journals. STUDY SELECTION: 965 systematic reviews (809 Cochrane reviews and 156 paper based reviews) published between 1995 and 2002. DATA SYNTHESIS: The methodological quality of primary studies was assessed in 854 of the 965 systematic reviews (88.5%). This occurred more often in Cochrane reviews than in paper based reviews (93.9% v 60.3%, P < 0.0001). Overall, only 496 (51.4%) used the quality assessment in the analysis and interpretation of the results or in their discussion, with no significant differences between Cochrane reviews and paper based reviews (52% v 49%, P = 0.58). The tools and methods used for quality assessment varied widely. CONCLUSIONS: Cochrane reviews fared better than systematic reviews published in paper based journals in terms of assessment of methodological quality of primary studies, although they both largely failed to take it into account in the interpretation of results. Methods for assessment of methodological quality by systematic reviews are still in their infancy and there is substantial room for improvement.

Cross-Sectional Studies↗

PubMed2006

Methodology for optimising location of new primary health care facilities in rural communities: a case study in KwaZulu-Natal, South Africa.

STUDY OBJECTIVE: To develop a quantitative methodology to optimally site new primary health care facilities so as to achieve the maximum population level increase in accessibility to care. The study aims to test the methodology in a rural community characterised by considerable heterogeneity in population distribution and health care access. DESIGN: A geographical information system was used to estimate travel time to the nearest primary health care facility for each of the 26 000 homesteads in the subdistrict. The homestead's travel time estimate was then converted into an impedance to care estimate using distance decay (in clinic use) data obtained from the subdistrict. A map of total person impedance/km(2) was then produced using a 3 km standard Gaussian filter. The resulting map was used to site a test clinic in the largest contiguous area of high person impedance. SETTING: Hlabisa health subdistrict, KwaZulu-Natal, South Africa. MAIN RESULTS: The population level increase in accessibility that would be achieved by the construction of the test clinic would be 3.6 times the increase in accessibility achieved by the construction of the newest clinic in the subdistrict. The corresponding ratio for increasing clinic coverage (% of the population within 60 minutes of care) would be 4.7. CONCLUSIONS: The methodology successfully identifies a locality for a new facility that would maximise the population level increase in accessibility to care. The same principles used in this research could also be applied in other settings. The methodology is of practical value in health research and practice and provides a framework for optimising location of new primary health care facilities.

Delivery of Health Care↗

PubMed1995

Variation in reported prevalences of hypertension in The Netherlands: the impact of methodological variables.

STUDY OBJECTIVE: To estimate the prevalence of hypertension in The Netherlands and to quantify the influence of methodological variables on the reported prevalences. DESIGN: A pooled analysis was performed based on reported age specific prevalences of hypertension. A logistic model was used to estimate the probability of hypertension. MAIN RESULTS: The age standardised prevalence of hypertension varies more than fivefold between studies carried out in The Netherlands. The probability of having hypertension was lower if blood pressure was measured at more than one point in time (Odds ratio 0.44 (OR) (95% confidence interval (95% CI) 0.38, 0.51) for men and 0.47 (0.41, 0.54) for women, and if the study was carried out more recently (OR 0.92 (0.91, 0.93) per year). The probability was higher if the study was carried out in a general practice (OR 1.14 (1.03, 1.27) for men and 1.52 (1.36, 1.69) for women). The inclusion of treated people as hypertensive yields contradictory results for men and women. CONCLUSIONS: The strong variation in prevalence is explained by methodology and by a period effect indicating a decrease of the prevalence of hypertension over time. Whether this decrease is true or caused by confounding due to unknown or unreported methodological variation over time is unknown. For future studies, a standardised method could reduce the influence of methodological variables and thereby the variation in reported prevalences.

Adult↗

PubMed2001

Understanding patients' preferences for treatment: the need for innovative methodologies.

Treatment selection is now much more consumer driven than in the past. However, there is a need to develop investigative methodological approaches that are sensitive to differences in patient preferences if full account is to be taken of what the patient sees as the best option in terms of different possible treatments available for a particular condition. Previous attitude research has been criticised because it does not provide insight into reasons why people hold different preferences or beliefs. A methodology is described which allows people to describe their concerns and values associated with different treatment options in their own words. This is the repertory grid method of eliciting personal constructs used in conjunction with generalised Procrustes analysis (GPA). An example of the use of this methodology is provided, drawn from research directed towards understanding people's beliefs about genetic technologies. A possible application of the method to understanding treatment preferences related to type 2 diabetes is also discussed. It is concluded that the use of innovative methodologies is essential if our understanding of patient preferences regarding treatment options is to have a significant impact on patient quality of life.

Adult↗

PubMed2003

Is the methodological quality of guidelines declining in the US? Comparison of the quality of US Agency for Health Care Policy and Research (AHCPR) guidelines with those published subsequently.

OBJECTIVE: To determine whether North American guidelines published subsequent to and in the same topic areas as those developed by the US Agency for Health Care Policy and Research (AHCPR) meet the same methodological criteria. STUDY DESIGN: A guideline appraisal instrument containing 30 criteria was used to evaluate the methodological quality of the AHCPR guidelines, "updates" of the AHCPR guidelines authored by others, and guidelines that referenced or were adapted from the AHCPR guidelines. The frequency with which the criteria appeared in each guideline was compared and an analysis was performed to determine guidelines with two key features of the ACHPR guidelines-multidisciplinary guideline development panels and systematic reviews of the literature. Data were extracted from the guidelines by one investigator and then checked for accuracy by the other. RESULTS: Fifty two guidelines identified by broad based searches were evaluated. 50% of the criteria were present in every AHCPR guideline. The AHCPR guidelines scored 80% or more on 24 of the 30 criteria compared with 14 for the "updates" and 11 for those that referenced/adapted the AHCPR guidelines. All of the 17 AHCPR guidelines had both multidisciplinary development panels and systematic reviews of the literature compared with five from the other two categories (p<0.05). CONCLUSIONS: North American guidelines developed subsequent to and in the same topic areas as the AHCPR guidelines are of substantially worse methodological quality and ignore key features important to guideline development. This finding contrasts with previously published conclusions that guideline methodological quality is improving over time.

Evidence-Based Medicine↗

PubMed2000

A scale of methodological quality for clinical studies of radiologic examinations.

PURPOSE: To develop and evaluate a scale for assessment of the methodological quality for clinical investigations of radiologic studies. MATERIALS AND METHODS: A scale was developed that included methodological standards compiled from established sources for assessing the methodological quality of study designs in clinical research and characteristics related to biases commonly observed in clinical radiologic research. The scale was composed of 15 standards and was tested with the results of 96 studies on imaging of liver hemangioma. Interrater reliability was measured between two observers by using percentage agreement and kappa statistics. Interrater reliability between two observers for a composite quality index that encompassed the 15 standards was measured with the intraclass correlation coefficient. RESULTS: Agreement between the two observers was almost perfect (kappa value, 0.8-1.0) for 11 standards and substantial (kappa value, 0.74-0.78) for four standards. Agreement between the observers with regard to the composite quality index also was high (intraclass correlation coefficient r, 0.91 [95% CI: 0.87, 0.94]). CONCLUSION: The scale appears to be reliable for the assessment of methodological quality of clinical investigations of radiologic studies.

Hemangioma↗

PubMed2004

[Assessment of research methodology on diagnostic laboratory test in Revista Clínica Española and Medicina Clínica].

BASIS: The identification of the methodological limitations of diagnostic research on laboratory tests is the basis in order to guide its enhancement and facilitate the application of the results to the clinical decisions. METHODS: Seventeen articles published in Revista Clínica Española and Medicina Clínica from 1997 to 2000 were analyzed, in which the sensitivity and specificity of a diagnostic laboratory test were determined. Some standardized criteria of methodological quality were independently applied by three investigators. RESULTS: A high frequency in the fulfillment of some key methodological aspects was observed: adequate description of the standard of reference (88%), of the test investigated (88%), of the clinical sample evaluated (71%), and of the prevention of the sequence bias (82%). The assessment of indeterminate results (12%), the test reproducibility (12%), or the description of the origin of the evaluated population (6%) were infrequent. CONCLUSION: The methodological defects of diagnostic laboratory research could be prevented through the collaboration with clinical services and with simple modifications of the trial's designs.

Clinical Laboratory Techniques↗

PubMed1991

A methodological appraisal of research on prognosis after transient ischemic attacks.

We analyzed existing research on the prognosis of patients who have had a transient ischemic attack to identify studies that adhere to basic methodological principles and to identify underinvestigated questions. Studies were eligible for analysis if they were published in peer-reviewed journals after 1950, written in English, and included at least 50 patients with transient ischemia. Studies that included patients with stroke were included only if they reported outcome rates separately for the subgroup of patients with transient ischemia. All eligible studies were extracted by one investigator who recorded adherence to six key methodological principles. Among 60 eligible studies, 54 were observational cohort studies and six were randomized trials. Adherence to the six methodological principles was as follows: eight studies included an adequate description of diagnostic criteria and of procedures used to assure adherence to the criteria, 54 used appropriate end points, two assembled inception cohorts, 10 included an adequate description of end point surveillance, 22 adequately reported and analyzed censored patients, and 10 included a multivariate analysis for predictive variables. No study adhered to all six principles, but two adhered to the three most important ones (appropriate end points, inception cohort, and adequate reporting and analysis of censored patients). Aspects of prognosis after transient ischemia that have not been completely investigated include the severity of subsequent strokes and methods for estimating the outcome risk for individual patients. We conclude that only a few published investigations on prognosis after transient ischemia are methodologically complete. This finding helps explain why it is difficult to interpret many studies. Further research is needed and should target underinvestigated topics.

Cohort Studies↗

PubMed1999

Methodological parameters influence the detection of right-to-left shunts by contrast transcranial Doppler ultrasonography.

BACKGROUND AND PURPOSE: Contrast transcranial Doppler ultrasonography is a new method to detect intracardiac right-to-left shunts, such as the patent foramen ovale. However, the methodology of the procedure varies considerably among investigators. This study was undertaken to assess the influence of methodological parameters on the results of the contrast transcranial Doppler examination in the detection of right-to-left shunts. METHODS: A total of 72 patients (mean age, 58.2+/-14.7 years) had a contrast transcranial Doppler ultrasonography examination. To study the influence of methodological factors, patients with evidence of a right-to-left shunt underwent repeated examinations with modified procedures. Parameters under investigation were the timing of the Valsalva maneuver, the dose of the contrast medium, and the patient's posture during the examination. RESULTS: The median contrast signal count was 58.5 and 48.0 (P<0.001) and the median latency of the first intracranially detected contrast signal was 12.5 and 8.5 seconds (P=0.05) when the Valsalva maneuver was performed 5 and 0 seconds after the start of the injection, respectively. Reducing the contrast medium dose from 10 to 5, 2.5, and 1.2 mL resulted in a decline of the median signal count from 54.5 to 28.5, 20.5, and 12.0 (P<0.01), respectively, while the latency of the first contrast signal increased from 13.3 to 14.0, 14.6, and 15.0 seconds (P<0.05). The sitting position also produced a lower signal count than the supine position (P<0.02). CONCLUSIONS: This study demonstrates that several essential methodological parameters influence the results of the contrast transcranial Doppler ultrasonography examination. Therefore, it is necessary to standardize the procedure to permit comparable quantitative assessments of the shunt volume. The findings of the present study suggest that 10 mL of contrast medium be injected with the patient in the supine position and that the Valsalva maneuver be performed 5 seconds after the start of the injection.

Adult↗

PubMed2001

Ethical and methodological issues in pedigree stroke research.

BACKGROUND: Stroke is a complex genetic disorder with a variable phenotype. Investigations of heritable factors in complex genetic disorders use pedigree and genetic techniques, which pose different ethical and methodological challenges than those routinely encountered in therapeutic research. Building consensus on acceptable research practices in this field is vital to the success of multicentered collaborations. SUMMARY OF REVIEW: We review important ethical and methodological concerns related to the collection, storage, and release of pedigree research information. The human studies aspects of pedigree research are complicated methodologically because individuals can be active or passive participants and pedigrees can be proband derived, partially validated, or fully validated. Current research ethics frameworks do not work well outside of a dyadic researcher-subject relationship. Privacy and confidentiality for family members must be considered in pedigree research. Investigators should anticipate potential conflicts of interest among family members when designing a pedigree research protocol. CONCLUSIONS: We propose a "proband-initiated contact" methodology in which the proband or the proband's designate allows identification of potential families without breaching the privacy of individuals in the family. In situations in which family history data are collected without direct contact between researchers and individuals in the proband's family, an Institutional Review Board may waive consent by family members after appropriate review of the protocol and application of rules for granting waivers of consent. Certificates of Confidentiality should be considered.

Confidentiality↗

PubMed2003

HIV sexual risk-reduction interventions for youth: a review and methodological critique of randomized controlled trials.

The authors review and provide a methodological critique of randomized controlled studies of HIV risk reduction interventions that measured sexual risk behavior outcomes with adolescents. Studies conducted in school, community, and health care settings were reviewed. Overall, 13 of 23 interventions (57%) were effective in reducing sexual risk behavior. Methodological strengths of extant studies included an emphasis on a theoretical framework, evaluation of both individualized and group-intervention formats, use of multiple assessments of risk behavior (including biological outcomes), and inclusion of efficacy and effectiveness trials. Methodological limitations included limited evaluation of theoretical mediators of risk reduction, failure to report effect sizes, and lack of sustained findings. Inconsistencies were found in data analytic procedures and reporting, including how nested designs, skewed data, and attrition were addressed. Recommendations for designing methodologically rigorous interventions are provided.

Adolescent↗

PubMedDate not supplied

HIV prevention, cost-utility analysis, and race/ethnicity: methodological considerations and recommendations.

In this methodological article, the author reviews 1) the disproportionate impact that HIV/AIDS is having on communities of color in the United States, 2) what is known about the cost-effectiveness of HIV prevention interventions for racial/ethnic minority communities (including the methods used in these studies), and 3) the relative lack of methodological guidance in the field for conducting economic evaluation studies specifically for communities of color. The author finds that race/ethnicity affects cost-utility analyses in several heretofore unrecognized ways. In this article, methodological techniques to address these concerns are proposed. In particular, the author recommends cost-utility analytic strategies that maximize comparability among studies and avoid the introduction of methodological discrimination.

Cost-Benefit Analysis↗

PubMedDate not supplied

A decision theoretic methodology for severity index development.

Severity indices are a key element in evaluation of health programs. But the methodologies used in development of such indices are rarely clearly defined. Moreover, there have been no tests of transportability of the index development methodologies that do exist, so there is no guarantee that panels of physicians convened by different facilitators would produce indices with similar performance characteristics. This paper describes a replicable index development strategy, a heart disease severity index developed by using that methodology, and a test of that methodology's transportability.

Coronary Disease↗