• search hit 2 of 8
Back to Result List

Prevalence dependent calibration of a predictive model for nasal carriage of methicillin-resistant Staphylococcus aureus

Please always quote using this URN: urn:nbn:de:bvb:20-opus-96091
  • Background Published models predicting nasal colonization with Methicillin-resistant Staphylococcus aureus among hospital admissions predominantly focus on separation of carriers from non-carriers and are frequently evaluated using measures of discrimination. In contrast, accurate estimation of carriage probability, which may inform decisions regarding treatment and infection control, is rarely assessed. Furthermore, no published models adjust for MRSA prevalence. Methods Using logistic regression, a scoring system (values from 0 toBackground Published models predicting nasal colonization with Methicillin-resistant Staphylococcus aureus among hospital admissions predominantly focus on separation of carriers from non-carriers and are frequently evaluated using measures of discrimination. In contrast, accurate estimation of carriage probability, which may inform decisions regarding treatment and infection control, is rarely assessed. Furthermore, no published models adjust for MRSA prevalence. Methods Using logistic regression, a scoring system (values from 0 to 200) predicting nasal carriage of MRSA was created using a derivation cohort of 3091 individuals admitted to a European tertiary referral center between July 2007 and March 2008. The expected positive predictive value of a rapid diagnostic test (GeneOhm, Becton & Dickinson Co.) was modeled using non-linear regression according to score. Models were validated on a second cohort from the same hospital consisting of 2043 patients admitted between August 2008 and January 2012. Our suggested correction score for prevalence was proportional to the log-transformed odds ratio between cohorts. Calibration before and after correction, i.e. accurate classification into arbitrary strata, was assessed with the Hosmer-Lemeshow-Test. Results Treating culture as reference, the rapid diagnostic test had positive predictive values of 64.8% and 54.0% in derivation and internal validation corhorts with prevalences of 2.3% and 1.7%, respectively. In addition to low prevalence, low positive predictive values were due to high proportion (> 66%) of mecA-negative Staphylococcus aureus among false positive results. Age, nursing home residence, admission through the medical emergency department, and ICD-10-GM admission diagnoses starting with “A” or “J” were associated with MRSA carriage and were thus included in the scoring system, which showed good calibration in predicting probability of carriage and the rapid diagnostic test’s expected positive predictive value. Calibration for both probability of carriage and expected positive predictive value in the internal validation cohort was improved by applying the correction score. Conclusions Given a set of patient parameters, the presented models accurately predict a) probability of nasal carriage of MRSA and b) a rapid diagnostic test’s expected positive predictive value. While the former can inform decisions regarding empiric antibiotic treatment and infection control, the latter can influence choice of screening method.show moreshow less

Download full text files

Export metadata

Additional Services

Share in Twitter Search Google Scholar Statistics
Metadaten
Author: Johannes Elias, Peter U. Heuschmann, Corinna Schmitt, Frithjof Eckhardt, Hartmut Boehm, Sebastian Maier, Annette Kolb-Mäurer, Hubertus Riedmiller, Wolfgang Müllges, Christoph Weisser, Christian Wunder, Matthias Frosch, Ulrich Vogel
URN:urn:nbn:de:bvb:20-opus-96091
Document Type:Journal article
Faculties:Medizinische Fakultät / Institut für Hygiene und Mikrobiologie
Medizinische Fakultät / Klinik und Poliklinik für Mund-, Kiefer- und Plastische Gesichtschirurgie
Medizinische Fakultät / Medizinische Klinik und Poliklinik I
Language:English
Parent Title (English):BMC Infectious Diseases
Year of Completion:2013
Source:In: BMC Infectious Diseases (2013) 13: 111, doi:10.1186/1471-2334-13-111
URL:http://www.biomedcentral.com/1471-2334/13/111
DOI:https://doi.org/10.1186/1471-2334-13-111
Dewey Decimal Classification:6 Technik, Medizin, angewandte Wissenschaften / 61 Medizin und Gesundheit / 610 Medizin und Gesundheit
Tag:Calibration; Clinical prediction rule; False positive reactions; Infection control; Methicillin-resistant staphylococcus aureus; Predictive value of tests
Release Date:2014/04/23
Collections:Open-Access-Publikationsfonds / Förderzeitraum 2013
Licence (German):License LogoCC BY: Creative-Commons-Lizenz: Namensnennung