Capture-mark-recapture to estimate the number of missed articles for systematic reviews in surgery

Abstract BACKGROUND: Systematic reviews are an important knowledge synthesis tool, but with new literature available each day, reviewers must balance identifying all relevant literature against timely synthesis. METHODS: This study tested capture-mark-recapture (CMR), an ecology-based technique, to estimate the total number of articles in the literature identified in a systematic review of adult trauma care quality indicators. RESULTS: The systematic review included 40 articles identified from online searches and citation references. The CMR model suggested that 3 (95% confidence interval [CI]: 0 to 6) articles were missed and the database search provided 93% (one-sided 95% CI: R83%) of known articles for inclusion in the systematic review. The search order used for identifying the articles was optimal among the 24 that could have been used. CONCLUSIONS: The CMR technique can be used in systematic reviews in surgery to estimate the closeness to capturing the total body of literature for a specific topic. Ó 2013 Elsevier Inc. All rights reserved. Systematic reviews are increasingly used in surgery to synthesize knowledge so that evidence can inform clinical practice (eg, guideline development). Exhaustive searching in multiple large bibliographic databases is time consuming and resource intensive, but it needs to be efficient so the results are presented before the information becomes outdated. However, this is difficult because the amount of literature that exists on any given topic is unknown. Capture-mark-recapture (CMR) is a technique originating in ecology that has been applied to systematic reviews of randomized controlled trials of interventions in osteoporosis, gastroenterology, and hematology 1-3 to estimate The project was supported by a Synthesis Grant (KRS-91770) from the Canadian Institutes of Health Research. Dr. Stelfox is supported by a New Investigator Award from the Canadian Institutes of Health Research and a Population Health Investigator Award from Alberta Innovates. Funding sources had no role in the design, conduct, or reporting of this study and we are unaware of any conflicts of interest. None of the authors have financial or professional conflicts of interest that would influence the conduct or reporting of this study. Drs. Stelfox, Foster, and Goldsmith had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Presented at the Cochrane Canada Symposium May 9, 2012, Winnipeg, Canada. * Corresponding author. The American Journal of Surgery (2013) 206, 439-440 the number of articles in the literature. The technique has not been evaluated in observational studies or surgical studies. We therefore tested CMR to estimate the total number of articles in the literature identified in a systematic review of adult trauma care quality indicators. We performed a scoping review to identify quality indicators for evaluating trauma care 4 and subsequently systematically reviewed the evidence. 5 Horizon estimates (estimated total population of articles) were calculated for full text review and final inclusion using the 4 step CMR technique: (1) capture an initial sample from a population of interest (eg, catch fish in lake); (2) mark the elements in the sample (eg, tag the fish); (3) release the sample back into the population (eg, release tagged fish back into lake); and (4) resample the population (catch fish from same lake to see how many are tagged). Articles found in our 1st database (MEDLINE) were marked as being retrieved from that search and compared with articles retrieved through subsequent searches (eg, Embase was the 2nd database). Articles identified through bibliography reviews were attributed to the originating electronic database. Poisson regression models were used to calculate fitted estimates of the cell counts (number of articles missed) and estimate the total horizon of articles (SAS v 9.2; SAS, Cary, NC). The results of the horizon estimate are shown in We repeated the process for articles selected for inclusion in the systematic review. The final horizon estimate was 43 (40 to 46) articles, representing a difference of 3 (0 to 6) articles between the projected total literature and the number of articles captured (40 articles). Thus, selection of articles for inclusion in the systematic review represents the capture of 93% (87% to 100%) of the estimated pool of available articles. The search order used for identifying the articles was optimal among the 24 that could have been used. CMR is a technique that can be applied to estimate the total number of relevant articles for a given topic. This study demonstrates that CMR can be successfully used for systematic reviews of observational studies in surgery. Future systematic reviews may consider including horizon estimates as possible stopping rules (eg, search until 80% of articles captured) to identify when a sufficient literature search has been completed. CMR may help improve the completeness and efficiency of systematic reviews

Systemic Membrane Defect in the Proximal Muscular Dystrophies

Abstract We studied lymphocyte capping in 61 patients with Duchenne, Becker, limb-girdle, facioscapulohumeral and congenital muscular dystrophies. All showed a markedly diminished percentage of capped cells when compared with 86 normal controls, providing support for previous evidence that an alteration in membrane fluidity may be a common pathogenic feature in several genetically distinct forms of proximal muscular dystrophy. Heterozygous carriers of Duchenne muscular dystrophy showed diminished capping that was indistinguishable from that of afflicted males and was often present even when serum enzyme levels were normal. Studies in 25 families with 16 suspected sporadic cases indicated that no more than four out of 30 afflicted males may represent new mutations. These findings imply that most cases of Duchenne dystrophy might be prevented by a population screening program for carrier females combined with prenatal detection of afflicted males. (N Engl J Med 299:841–846, 1978

Teleoncology in the Department of Defense: A tale of two systems

ABSTRACT Two telemedicine networks were developed for the purpose of conducting multidisciplinary oncology ("teleoncology") conferences. The infrastructure of each system differed: one system was Internet-based; the other was delivered via Integrated Services Digital Network (ISDN) lines. The purpose of this study was to describe the infrastructure and cost, consultative process, technical aspects, and conference format of the two teleoncology programs. The two systems' technical aspects, participant satisfaction with the systems, and conference participation were compared qualitatively. Assessment of the technical aspects of the systems suggested that each had distinct advantages. Survey results indicated that provider satisfaction with the technical and logistical aspects of each type of teleoncology conference was high. The present study may prove helpful for individuals who are considering implementing their own teleoncology programs. T ELEM ED ICIN E H A S BEEN D ESCRIBED as the practice of medicine at a distance. 1 Telemedicine applications have been used in nearly every field of medicine, including radiology, psychiatry, dermatology, and cardiology. One aspect of telemedicine that has become increasingly common is teleoncology, the delivery of oncology services from a distance. 1 Teleoncology programs offer a variety of potential benefits, including enhancing primary care managers' access to referrals, expand opportunities for continuing medical education (CME) credits, reduction of unnecessary referrals, and smooth coordination of patient care. To date, only a handful of studies have examined the topic of teleoncology. Investigators have looked at the use of interactive video to provide psychosocial support, 2 the use of interactive video and proxy examiners to provide direct patient care, 3 and the use of teleoncology to facilitate consultation by cancer specialists to geographically remote primary care providers

On the origin and evolution of the material in 67P/Churyumov-Gerasimenko

International audiencePrimitive objects like comets hold important information on the material that formed our solar system. Several comets have been visited by spacecraft and many more have been observed through Earth- and space-based telescopes. Still our understanding remains limited. Molecular abundances in comets have been shown to be similar to interstellar ices and thus indicate that common processes and conditions were involved in their formation. The samples returned by the Stardust mission to comet Wild 2 showed that the bulk refractory material was processed by high temperatures in the vicinity of the early sun. The recent Rosetta mission acquired a wealth of new data on the composition of comet 67P/Churyumov-Gerasimenko (hereafter 67P/C-G) and complemented earlier observations of other comets. The isotopic, elemental, and molecular abundances of the volatile, semi-volatile, and refractory phases brought many new insights into the origin and processing of the incorporated material. The emerging picture after Rosetta is that at least part of the volatile material was formed before the solar system and that cometary nuclei agglomerated over a wide range of heliocentric distances, different from where they are found today. Deviations from bulk solar system abundances indicate that the material was not fully homogenized at the location of comet formation, despite the radial mixing implied by the Stardust results. Post-formation evolution of the material might play an important role, which further complicates the picture. This paper discusses these major findings of the Rosetta mission with respect to the origin of the material and puts them in the context of what we know from other comets and solar system objects

A century of trends in adult human height

Being taller is associated with enhanced longevity, and higher education and earnings. We reanalysed 1472 population-based studies, with measurement of height on more than 18.6 million participants to estimate mean height for people born between 1896 and 1996 in 200 countries. The largest gain in adult height over the past century has occurred in South Korean women and Iranian men, who became 20.2 cm (95% credible interval 17.5-22.7) and 16.5 cm (13.3-19.7) taller, respectively. In contrast, there was little change in adult height in some sub-Saharan African countries and in South Asia over the century of analysis. The tallest people over these 100 years are men born in the Netherlands in the last quarter of 20th century, whose average heights surpassed 182.5 cm, and the shortest were women born in Guatemala in 1896 (140.3 cm; 135.8-144.8). The height differential between the tallest and shortest populations was 19-20 cm a century ago, and has remained the same for women and increased for men a century later despite substantial changes in the ranking of countries

Cybercrime prevention: theory and applications

This book articulates how crime prevention research and practice can be reimagined for an increasingly digital world.Russsell Brewer, Melissa de Vel-Palumbo, Alice Hutchings, Thomas Holt, Andrew Goldsmith and David Maimo