The Cochrane Methodology Register (CMR) is a bibliography of publications that report on methods used in the conduct of controlled trials. It includes journal articles, books, and conference proceedings, and the content is sourced from MEDLINE and hand searches. CMR contains studies of methods used in reviews and more general methodological studies that could be relevant to anyone preparing systematic reviews. CMR records contain the title of the article, information on where it was published (bibliographic details), and, in some cases, a summary of the article. They do not contain the full text of the article.
The CMR was produced by the Cochrane UK, until 31st May 2012. There are currently no plans to reinstate the CMR and it is not receiving updates.* If you have any queries, please contact the Cochrane Community Service Team (support@cochrane.org).
The Publishers, John Wiley & Sons Ltd, thanks Update Software for the continued use of their data formats in the Cochrane Methodology Register (CMR).
*Last update in January 2019.
| Title | The Newcastle-Ottawa Scale (NOS) for assessing the quality of nonrandomised studies in meta-analyses [abstract] |
| Authors | Wells GA, Shea B, O'Connell D, Peterson J, Welch V, Tugwell P. |
| Source | 3rd Symposium on Systematic Reviews: Beyond the Basics; 2000 Jul 3-5; Oxford, UK. |
| Date of publication | 2000 |
| Pages | 15 |
| Abstract | Nonrandomised studies, including case-control and cohort studies, can be challenging to implement and conduct. Assessment of the quality of such studies is essential for a proper understanding of the role that a particular study should have when considering the results of a meta-analysis of nonrandomised studies. The Newcastle-Ottawa Scale (NOS) has been developed for assessing the quality of nonrandomised studies with its design, content and ease of use directed to the task of incorporating the quality assessments in the interpretation of meta-analytic results. A 'star system' has been developed in which a study is judged on three broad perspectives: the selection of the study groups; the comparability of the groups; and the ascertainment of either the exposure or outcome of interest for case-control or cohort studies respectively. The face/content validity of the NOS has been established based on a critical review of the items by several experts in the field who evaluated its clarity and completeness for the specific task of assessing the quality of studies to be used in a meta-analysis. Also, the NOS has been refined based on experience using it in several projects, in particular, a project assessing the association of breast cancer associated with hormone replacement therapy in postmenopausal women and a project assessing the association of connective tissue disease with silicone breast implants. The evaluation of the NOS is currently in progress. Its content validity and inter-rater reliability have been established. Its criterion validity with comparisons to more comprehensive but cumbersome scales and its intra-rater reliability are currently being examined. An assessment plan is being formulated for evaluating its construct validity with consideration of the theoretical relationship of the NOS to external criteria and the internal structure of the NOS components. OTHER PUBLICATIONS OF THIS RESEARCH: Wells G, Brodsky L, O'Connell D, Shea B, Henry D, Mayank S, Tugwell P. An evaluation of the Newcastle Ottawa Scale: an assessment tool for evaluating the quality of non-randomized studies [abstract] XI Cochrane Colloquium: Evidence, Health Care and Culture; 2003 Oct 26-31; Barcelona, Spain:26. |
| CMR keywords | CMR: Evaluation methodology - non-randomised studies - quality assessment;CMRA9 |
| Correspondence address | Professor GA Wells, Department of Epidemiology and Community Medicine, University of Ottawa, Room 3227A, 451 Smyth Road, Ottawa, Ontario K1H 8M5, Canada. |
| Reference type |