Bmc Med Res Methodol
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Bmc Med Res Methodol · Jan 2009
Using ordinal logistic regression to evaluate the performance of laser-Doppler predictions of burn-healing time.
Laser-Doppler imaging (LDI) of cutaneous blood flow is beginning to be used by burn surgeons to predict the healing time of burn wounds; predicted healing time is used to determine wound treatment as either dressings or surgery. In this paper, we do a statistical analysis of the performance of the technique. ⋯ Modeling healing time is a complex statistical problem, with random effects due to multiple burn areas per individual, and censoring caused by patients missing hospital visits and undergoing surgery. This analysis applies state-of-the art statistical methods such as the bootstrap and permutation tests to a medical problem of topical interest. New medical findings are that age and %TBSA are not important predictors of healing time when the LDI results are known, whereas gender does influence recovery time, even when blood flow is controlled for.The conclusion regarding the palette is that an optimum three-color palette can be chosen 'automatically', but the optimum choice of a 5-color palette cannot be made solely by optimizing the percentage of correct diagnoses.
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Bmc Med Res Methodol · Jun 2008
Comparative StudyChallenges of self-reported medical conditions and electronic medical records among members of a large military cohort.
Self-reported medical history data are frequently used in epidemiological studies. Self-reported diagnoses may differ from medical record diagnoses due to poor patient-clinician communication, self-diagnosis in the absence of a satisfactory explanation for symptoms, or the "health literacy" of the patient. ⋯ This report highlights the challenges of using self-reported medical data and electronic medical records data, but illustrates that agreement between the two data sources increases with increased surveillance period of medical records. Self-reported medical data may be sufficient for ruling out history of a particular condition whereas prevalence studies may be best served by using an objective measure of medical conditions found in electronic healthcare records. Defining medical conditions from multiple sources in large, long-term prospective cohorts will reinforce the value of the study, particularly during the initial years when prevalence for many conditions may still be low.
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Bmc Med Res Methodol · May 2008
Comparative StudyOn reporting results from randomized controlled trials with recurrent events.
Evidence-based medicine has been advanced by the use of standards for reporting the design and methodology of randomized controlled trials (RCT). Indeed, without this information it is difficult to assess the quality of evidence from an RCT. Although a variety of statistical methods are available for the analysis of recurrent events, reporting the effect of an intervention on outcomes that recur is an area that remains poorly understood in clinical research. The purpose of this paper is to outline guidelines for reporting results from RCTs where the outcome of interest is a recurrent event. ⋯ Our guidelines for reporting results from an RCT involving a recurrent event suggest that the study question and the objectives of the trial, such as assessing comparable groups and estimating effect size, should determine the statistical methods. The guidelines should allow clinical researchers to report appropriate measures from an RCT for understanding the effect of intervention on the occurrence of a recurrent event.
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Bmc Med Res Methodol · Jan 2008
Randomized Controlled Trial Comparative StudyTowards socially inclusive research: an evaluation of telephone questionnaire administration in a multilingual population.
Missing data may bias the results of clinical trials and other studies. This study describes the response rate, questionnaire responses and financial costs associated with offering participants from a multilingual population the option to complete questionnaires over the telephone. ⋯ Studies requiring data to be collected by questionnaire may obtain higher response rates from both English and non-English speakers when a choice of telephone or postal administration (and where necessary, an interpreter)is offered compared to offering postal administration only. This approach will, however, incur additional research costs and uncertainty remains about the equivalence of responses obtained from the two methods.
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Bmc Med Res Methodol · Jan 2008
Comparative StudyResponsiveness of five condition-specific and generic outcome assessment instruments for chronic pain.
Changes of health and quality-of-life in chronic conditions are mostly small and require specific and sensitive instruments. The aim of this study was to determine and compare responsiveness, i.e. the sensitivity to change of five outcome instruments for effect measurement in chronic pain. ⋯ The MPI was most responsive in all comparable domains followed by the SF-36. The pain-specific MPI and the generic SF-36 can be recommended for comprehensive and specific bio-psycho-social effect measurement of health and quality-of-life in chronic pain.