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[Comorbidity between eating disorders and anxiety disorders. First part: methodological review].

UNLABELLED: The objective of our work is to conduct a critical literature review on studies assessing the prevalence of anxiety disorders (AD) in subjects with eating disorders (ED) (anorexia nervosa and bulimia nervosa). In the first part (this paper), we will discuss methodological issues relevant to comorbidity studies between ED and AD. METHOD: We performed a manual and computerised search (Medline) for all published studies on comorbidity between ED and AD, limiting our search to the 1985-2002 period, in order to get sufficiently homogeneous diagnostic criteria for both categories of disorders (most often RDC, DSM III, DSM Ill-R, or DSM IV criteria). RESULTS: We review methodological issues regarding population sources, general methodological procedures, diagnostic criteria for ED and AD, diagnostic instruments, age of subjects and course of the eating disorder. DISCUSSION: We give implications for reviewing the results of published studies and planing future research.

Adult↗

Detection of antiendometrial antibodies in patients with endometriosis: methodological issues.

OBJECTIVE: To determine if methodological reasons explain previous inability of a single investigator to detect antiendometrial antibodies in patients with endometriosis by indirect immunofluorescence (IIF). DESIGN: Sera of selected patients were tested by standard IIF and recently reported methodology. Alternate diluent experiments were conducted to explain discordant results. SETTING: Sera were obtained preoperatively, and testing was completed in an institutional research laboratory. Results are compared with surgical findings. PATIENTS/PARTICIPANTS: Patients, seven with endometriosis and six without endometriosis, 40 years of age or less who are presenting for gynecological surgery. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Indirect immunofluorescence was graded according to the presence or absence of cytoplasmic staining, intensity of the staining, and the lowest dilution at which staining was observed. RESULTS: The standard IIF method repeatedly demonstrated the presence of cytoplasmic staining for the presence of antiendometrial antibodies in patients with endometriosis, whereas modified methods did not produce similar positive staining results. During the alternate dilution experiments, when fluorescein isothiocyanate conjugate (FITC) was diluted in animal sera, negative results were obtained. CONCLUSIONS: The variations used in alternate methodology and failure to titrate FITC reported by other investigators are possible reasons for false-negative results reported.

Adult↗

A new methodology to measure load transfer through the forearm using multiple universal force sensors.

Previous approaches to measuring forces in the forearm have made the assumption that forces acting in the radius and ulna are uniaxial near the wrist and elbow. To accurately describe forces in the forearm and the forces in the interosseous ligament, we have developed a new methodology to quantitatively determine the 3-D force vectors acting in forearm structures when a compressive load is applied to the hand. A materials testing machine equipped with a six degree-of-freedom universal force-moment sensor (UFS) was employed to apply a uniaxial compressive force to cadaveric forearms gripped at the hand and humerus. Miniature UFSs were implanted into the distal radius and proximal ulna to measure force vectors there. A 3-D digitizing device was used to measure transformations between UFS coordinate systems, utilized for calculating the force vectors in the distal ulna, proximal radius, and the interosseous ligament (IOL). This method was found to be repeatable to within 3 N, and accurate to within 2 N for force magnitudes. Computer models of the forearm, generated from CT scans, were used to visualize the force vectors in 3-D. Application of this methodology to eight forearm specimens showed that the radius carries most of the load at the wrist while force in the IOL relieves load acting in the radius at the mid-forearm. For a 136 N applied hand force, the force in the IOL was 36 + 21 N. Advantages of this methodology include the determination of 3-D force vectors, especially those in the IOL, as well as computer generated 3-D visualization of results.

Biomechanical Phenomena↗

A methodology for objective assessment of errors: an example using an endoscopic sinus surgery simulator.

A well-proven methodology (the modified Delphi method) was used to generate a first-order approximation of errors that should be measured in a virtual reality surgical simulator (the ES3). The methodology and the errors derived were crafted in such a way as to be generalizable. Although some of the error measures are specific for sinus surgery, the same type of methodology can be used for other otolaryngologic, general, and [table: see text] subspecialty surgical procedures. The value of this process is that it can provide a uniform framework for investigators in surgical education and training to establish error measurements in their particular procedures or disciplines and to generate data and outcomes that are comparable, interoperable, and sharable with other investigators. Admittedly, the process is time consuming and rigorous, but it does provide a solid scientific basis to generate evidence-based data for the validation of training methods and for outcomes analysis.

Clinical Competence↗

Methodological issues in assessing resilience in maltreated children.

OBJECTIVE: Efforts to assess resilience in maltreated children reveal methodological difficulties in developing operational definitions of resilience. This paper discusses six methodological issues: (1) distinguishing between resilience and factors promoting or reducing resilience; (2) choosing sources of measures; (3) determining how many sources and measures to use; (4) selecting scoring criteria to indicate resilience; (5) determining when to measure resilience; and (6) examining the stability of resilience over time. CONCLUSIONS: Understanding resilience in maltreated children is important for developing ways to promote competence in more vulnerable maltreated children. Although the classification of children as resilient depends on how resilience is defined, there is no consensus regarding operational definitions of resilience. By focusing more attention on the issue of resilience, research on maltreated children can help resolve methodological difficulties in defining and measuring the concept.

Adaptation, Psychological↗

Rapid appraisal methodology for 'health for all' policy formulation analysis.

BACKGROUND: Although in the last 20 years, the WHO 'Health for All' principles have been widely used in national, regional and local health policy documents, there is still a gap in the literature regarding how to appraise or compare them, which weakens the social accountability process. METHODOLOGY: A new, rapid approach to analyse the formulation of health policies is proposed. It is based on the selection of a small number of tracers and the development of a gold standard to be completed with input from a review of the literature, and opinions of expert panel members. This methodology has been empirically applied to the health strategies of two Spanish regions (Catalonia and Valencia). RESULTS: A framework for analysis was produced containing three dimensions: timing (early or late policy options), action level (individuals or social focus) and equity (social class, gender and ethnic groups). The health problems selected as tracers were HIV/AIDS, traffic injuries and ageing-related disabilities. In the two regions studied, the policies formulated for HIV/AIDS and age-related disabilities provide interventions late in the evolution of the health problem. The strategy established in the region of Valencia is more community-oriented than in Catalonia. Neither region had implemented specific policies regarding social class, gender or ethnic groups. INTERPRETATION: The methodology proposed here makes it possible to map the formulation of Health Strategies, compare different geographical areas and even forecast the policies' usefulness. The simplicity of the method, together with the fact that citizens and politicians alike can easily understand its results are major advantages. For the framework to be fully useful, it will be necessary to build evidence-based policy databases.

Accidents, Traffic↗

Rook methodology: a flexible framework for exact test development in the matching paradigm.

As well as supplying a means of enumerating permutations, rook methodology provides a flexible and fertile analytic framework that can facilitate statistical test development in applied settings. Four applications in psychology, where rook methodology provides exact small-sample tests, are described. They are (a) matching under uncertainty, (b) ordered spatial memory, (c) rater agreement under uncertainty, and (d) multiple object relocation. An online computer program, that supplies an exact small-sample test of hypotheses within the rook paradigm, is outlined. The program, which exploits rook methodology to enumerate permutations, may be accessed and executed via the Internet using an ordinary browser.

Computer Simulation↗

Reporting methodology protocols in three acute care journals.

Our study compared the reporting of methodology protocol details in three acute care journals, Annals of Emergency Medicine, Critical Care Medicine, and Journal of Trauma. Eleven criteria previously reported for evaluation of clinical trials in the medical literature were used. These were eligibility criteria, admission before allocation, random allocation, method of randomization, patients' blindness to treatment, blind assessment of outcome, treatment complications, loss to follow-up, statistical methods, statistical analysis, and power. All prospective, interventional, controlled trials appearing in the journals from January 1980 to June 1983 were identified. A total of 45 trials was found. Each study was read independently by two reviewers to determine whether each of the 11 criteria was reported clearly, reported unclearly, or not applicable. Disagreements were resolved by a third reader (adjudicator). The results are reported as the mean proportion of items clearly reported plus or minus the standard deviation: Annals of Emergency Medicine (n = 16), 0.40 +/- 0.18; Journal of Trauma (n = 18), 0.41 +/- 0.24; Critical Care Medicine (n = 11), 0.35 +/- 0.18. A one-way analysis of variance found no statistically significant difference between journals with respect to these proportions (P = .75). The study reveals that these journals, as judged by these criteria, do not report enough methodologic information to allow assessment of bias-reducing techniques and statistical methodology.

Analysis of Variance↗

The Ontario Prehospital Advanced Life Support (OPALS) study Part II: Rationale and methodology for trauma and respiratory distress patients. OPALS Study Group.

The Ontario Prehospital Advanced Life Support (OPALS) Study represents the largest prehospital study yet conducted, worldwide. This study will involve more than 25,000 cardiac arrest, trauma, and critically ill patients over an 8-year period (1994-2002). The current article, Part II, describes in detail the rationale and methodology for major trauma and respiratory distress patients and for an economic evaluation of Advanced Life Support (ALS) programs in the OPALS Study. The OPALS Study, using a rigorous controlled methodology and a large sample size, should clearly indicate the benefit in trauma and respiratory distress patient survival and morbidity that results from the widespread introduction of prehospital ALS programs to communities of many different sizes. [Stiell IG, Wells GA, Spaite DW, Nichol G, O'Brien B, Munkley DP, Field BJ, Lyver MB, Luinstra LG, Dagnone E, Campeau T, Ward R, Anderson S, for the OPALS Study Group: The Ontario Prehospital Advanced Life Support (OPALS) Study Part II: Rationale and methodology for trauma and respiratory distress patients.

Emergency Medical Services↗

[Factors conditioning primary care services utilization. Empirical evidence and methodological inconsistencies].

INTRODUCTION: In Spain, the degree and characteristics of primary care services utilization have been the subject of analysis since at least the 1980s. One of the main reasons for this interest is to assess the extent to which utilization matches primary care needs. In fact, the provision of an adequate health service for those who most need it is a generally accepted priority. FACTORS CONDITIONING USE: The evidence shows that individual characteristics, mainly health status, are the factors most closely related to primary care utilization. Other personal characteristics, such as gender and age, could act as modulators of health care need. Some family and/or cultural variables, as well as factors related to the health care professional and institutions, could explain some of the observed variability in primary care services utilization. Socioeconomic variables, such as income, reveal a paradox. From an aggregate perspective, income is the main determinant of utilization as well as of health care expenditure. When data are analyzed for individuals, however, income is not related to primary health utilization. METHODOLOGICAL INCONSISTENCIES: The situation is controversial, with methodological implications and, above all, consequences for the assessment of the efficiency in primary care utilization. Review of the literature reveals certain methodological inconsistencies that could at least partly explain the disparity of the empirical results. Among others, the following flaws can be highlighted: design problems, measurement errors, misspecification, and misleading statistical methods.Some solutions, among others, are quasi-experiments, the use of large administrative databases and of primary data sources (design problems); differentiation between types of utilization and between units of analysis other than consultations, and correction of measurement errors in the explanatory variables (measurement errors); consideration of relevant explanatory variables (misspecification); and the use of multilevel models (statistical methods).

Adolescent↗

Study of a predictive methodology for quantification and mapping of the radon-222 exhalation rate.

We propose a new methodology for predicting areas with a strong potential for radon (222Rn) exhalation at the soil surface. This methodology is based on the Rn exhalation rate quantification, starting from a precise characterisation of the main local geological and pedological parameters that control the radon source and its transport to the soil/atmosphere interface. It combines a cross mapping analysis of these parameters into a geographic information system with a model of the Rn vertical transport by diffusion in the soil. The rock and soil chemical and physical properties define the entry parameters of this code (named TRACHGEO) which calculates the radon flux density at the surface. This methodology is validated from in situ measurements of radon levels at the soil/atmosphere interface and in dwellings. We apply this approach to an area located in western France and characterised by a basement displaying a heterogeneous radon source potential, as previously demonstrated by lelsch et al. (J. Environ. Radioactivity 53(1) (2001) 75). The new results obtained show that spatial heterogeneity of pedological characteristics in addition to basement geochemistry--must be taken into account to improve the mapping resolution. The TRACHGEO forecasts explain the Rn exhalation variability on a larger scale and in general correlate well with in situ observations. Moreover, the radon-prone sectors identified by this approach generally correspond to the location of the dwellings showing the highest radon concentrations.

France↗

The relationship between psychosocial work characteristics and low back pain: underlying methodological issues.

OBJECTIVE: To evaluate the current epidemiological evidence linking psychosocial work characteristics with low back pain. BACKGROUND: Psychosocial work characteristics have been widely evaluated as potential risk factors for low back injury. However, studies with different study populations and using various types of measures have had conflicting results. METHODS: This review is the most extensive to date, reviewing 66 articles that have provided empirical evidence about the relationship between psychosocial work characteristics and initial reporting of lower back pain. The studies are reviewed with an emphasis on certain methodological issues: controlling for potential confounding; timing of the data collection; and measurement of the exposures and outcomes. RESULTS: The results of this review suggest that controlling for potential confounding from occupational biomechanical demands had a large influence on the associations found between psychosocial work characteristics and lower back pain. In addition, the use of accurate and reliable measures for the occupational exposures (biomechanical and psychosocial) and the lower back pain outcomes appears to influence the strength of the associations found between psychosocial work characteristics and lower back pain. CONCLUSION: Given the methodological concerns discussed in this review, it is difficult to draw strong causal inferences from this literature. However, it does appear that psychosocial characteristics are related to some lower back pain outcomes, and that employees' reactions to psychosocial work characteristics (e.g., job dissatisfaction and job stress) are more consistently related to lower back pain than are the psychosocial work characteristics themselves (e.g., work overload, lack of influence over work, quality of relationships with coworkers). RELEVANCE: This review attempts to identify and address methodological issues in the literature evaluating the relationship between psychosocial work characteristics and lower back pain. Implications for future research are presented.

Humans↗

Methodology for estimating soil carbon for the forest carbon budget model of the United States, 2001.

The largest carbon (C) pool in United States forests is the soil C pool. We present methodology and soil C pool estimates used in the FORCARB model, which estimates and projects forest carbon budgets for the United States. The methodology balances knowledge, uncertainties, and ease of use. The estimates are calculated using the USDA Natural Resources Conservation Service STATSGO database, with soil dynamics following assumptions based on results of site-specific studies, and area estimates from the USDA Forest Service. Forest Inventory and Analysis data and national-level land cover data sets. Harvesting is assumed to have no effect on soil C. Land use change and forest type transitions affect soil C. We apply the methodology to the southeastern region of the United States as a case study.

Carbon↗

Net carbon flux from agricultural ecosystems: methodology for full carbon cycle analyses.

Agricultural ecosystems have the potential to sequester carbon in soils by altering agricultural management practices (i.e. tillage practice, cover crops, and crop rotation) and using agricultural inputs (i.e. fertilizers and irrigation) more efficiently. Changes in agricultural practices can also cause changes in CO2 emissions associated with these practices. In order to account for changes in net CO2 emissions, and thereby estimate the overall impact of carbon sequestration initiatives on the atmospheric CO2 pool, we use a methodology for full carbon cycle analysis of agricultural ecosystems. The analysis accounts for changes in carbon sequestration and emission rates with time, and results in values representing a change in net carbon flux. Comparison among values of net carbon flux for two or more systems, using the initial system as a baseline value, results in a value for relative net carbon flux. Some results from using the full carbon cycle methodology, along with US national average values for agricultural inputs, indicate that the net carbon flux averaged over all crops following conversion from conventional tillage to no-till is -189 kg C ha(-1) year(-1) (a negative value indicates net transfer of carbon from the atmosphere). The relative net carbon flux, using conventional tillage as the baseline, is -371 kg C ha(-1) year(-1), which represents the total atmospheric CO2 reduction caused by changing tillage practices. The methodology used here illustrates the importance of (1) delineating system boundaries, (2) including CO2 emissions associated with sequestration initiatives in the accounting process, and (3) comparing the new management practices associated with sequestration initiatives with the original management practices to obtain the true impact of sequestration projects on the atmospheric CO2 pool.

Agriculture↗

Posttraumatic disorders following injury: an empirical and methodological review.

Although there has been a marked increase in research on psychological disorders following physical injury in recent years, there are many discrepancies between the reported findings. This paper reviews the prevalence outcomes of recent studies of the mental health sequelae of physical injury with a focus on posttraumatic stress disorder (PTSD), acute stress disorder (ASD), and depression. The review critically outlines some of the methodological factors that may have contributed to these discrepancies. The phenomenological overlap between organic and psychogenic symptoms, the use of narcotic analgesia, the role of brain injury, the timing and content of assessments, and litigation are discussed in terms of their potential to confound findings with this population. Recommendations are proposed to clarify methodological approaches in this area. It is suggested that a clearer understanding of the psychological effects of physical injury will require the widespread adoption of more rigorous, standardized and transparent methodological procedures.

Depression↗

Interpersonal functioning among women reporting a history of childhood sexual abuse: empirical findings and methodological issues.

A subset of research exploring the long-term impact of child sexual abuse (CSA) has examined the adult interpersonal functioning of female survivors. The present review discusses empirical findings and critical methodological issues related to this important but often overlooked aspect of adult adjustment. Though characterized by several methodological limitations, this literature, as a whole, suggests that early sexual abuse represents a risk factor for a range of interpersonal dysfunction among female survivors, including problems with intimate partner relations, disturbed sexual functioning, and difficulties in the parental role. Suggested methodological improvements for future research include new approaches to the measurement of CSA and interpersonal variables, the need for comprehensive assessment of significant third variables, and the use of more representative sampling strategies.

Adult↗

PCR methodology as a valuable tool for identification of endodontic pathogens.

OBJECTIVES: This paper reviews the principles of polymerase chain reaction (PCR) methodology, its application in identification of endodontic pathogens and the perspectives regarding the knowledge to be reached with the use of this highly sensitive, specific and accurate methodology as a microbial identification test. DATA SOURCES: Studies published in the medical, dental and biological literature. STUDY SELECTION: Evaluation of published epidemiological studies examining the endodontic microbiota through PCR methodology. CONCLUSIONS: PCR technology has enabled the detection of bacterial species that are difficult or even impossible to culture as well as cultivable bacterial strains showing a phenotypically divergent or convergent behaviour. Moreover, PCR is more rapid, much more sensitive, and more accurate when compared with culture. Its use in endodontics to investigate the microbiota associated with infected root canals has expanded the knowledge on the bacteria involved in the pathogenesis of periradicular diseases. For instance, Tannerella forsythensis (formerly Bacteroides forsythus), Treponema denticola, other Treponema species, Dialister pneumosintes, and Prevotella tannerae were detected in infected root canals for the first time and in high prevalence when using PCR analysis. The diversity of endodontic microbiota has been demonstrated by studies using PCR amplification, cloning and sequencing of the PCR products. Moreover, other fastidious bacterial species, such as Porphyromonas endodontalis, Porphyromonas gingivalis and some Eubacterium spp., have been reported in endodontic infections at a higher prevalence than those reported by culture procedures.

Bacteria↗

SCAP: a new methodology for safety management based on feedback from credible accident-probabilistic fault tree analysis system.

As it is conventionally done, strategies for incorporating accident--prevention measures in any hazardous chemical process industry are developed on the basis of input from risk assessment. However, the two steps-- risk assessment and hazard reduction (or safety) measures--are not linked interactively in the existing methodologies. This prevents a quantitative assessment of the impacts of safety measures on risk control. We have made an attempt to develop a methodology in which risk assessment steps are interactively linked with implementation of safety measures. The resultant system tells us the extent of reduction of risk by each successive safety measure. It also tells based on sophisticated maximum credible accident analysis (MCAA) and probabilistic fault tree analysis (PFTA) whether a given unit can ever be made 'safe'. The application of the methodology has been illustrated with a case study.

Accident Prevention↗