Strengthening the Reporting of Observational Studies in Epidemiology (STROBE): Explanation and Elaboration

Abstract

Much medical research is observational. The reporting of observational studies is often of insufficient quality. Poor reporting hampers the assessment of the strengths and weaknesses of a study and the generalizability of its results. Taking into account empirical evidence and theoretical considerations, a group of methodologists, researchers, and editors developed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) recommendations to improve the quality of reporting of observational studies.The STROBE Statement consists of a checklist of 22 items, which relate to the title, abstract, introduction, methods, results and discussion sections of articles. Eighteen items are common to cohort studies, case-control studies and cross-sectional studies and four are specific to each of the three study designs. The STROBE Statement provides guidance to authors about how to improve the reporting of observational studies and facilitates critical appraisal and interpretation of studies by reviewers, journal editors and readers.This explanatory and elaboration document is intended to enhance the use, understanding, and dissemination of the STROBE Statement. The meaning and rationale for each checklist item are presented. For each item, one or several published examples and, where possible, references to relevant empirical studies and methodological literature are provided. Examples of useful flow diagrams are also included. The STROBE Statement, this document, and the associated web site (http://www.strobe-statement.org) should be helpful resources to improve reporting of observational research. (Epidemiology 2007;18: 805-835) R ational health care practices require knowledge about the etiology and pathogenesis, diagnosis, prognosis and treatment of diseases. Randomized trials provide valuable evidence about treatments and other interventions. However, much of clinical or public health knowledge comes from observational research. 1 About nine of ten research papers published in clinical speciality journals describe observational research. 2,3 The STROBE StatementReporting of observational research is often not detailed and clear enough to assess the strengths and weaknesses of the investigation. 4,5 To improve the reporting of observational research, we developed a checklist of items that should be addressed: the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement (Table 1). Items relate to title, abstract, introduction, methods, results and discussion sections of articles. The STROBE Statement has recently been published in several journals. 6 Our aim is to ensure clear presentation of what was planned, done, and found in an observational study. We stress that the recommendations are not prescriptions for setting up or conducting studies, nor do they dictate methodology or mandate a uniform presentation.STROBE provides general reporting recommendations for descriptive observational studies and studies that investigate 805associations between expos...

The impact of postoperative intensive care on outcomes in elective neurosurgical patients in good physical condition: a single centre propensity case-matched study

“…This study was performed as a case-control study in accordance with the recommendations of the STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) consensus statement. 9 We reviewed the last three years of elective neurosurgical cases performed by a single surgeon at Nara Medical University and extracted the records of 296 consecutive neurosurgical patients who were American Society of Anesthesiologists' (ASA) physical status I-II.…”

What Are the Levels of Evidence on Which We Base Decisions for Surgical Management of Lower Extremity Bone Tumors?

“…The STROBE checklist was developed by a multinational group of methodologists, researchers, and journal editors to guide authors of observational studies [35]. Whereas the reporting of observational studies is often not clear enough to allow assessment of strengths and weaknesses, STROBE specifically considers sources of bias and clarifies the interpretation and applicability of a study's results and conclusions [34].…”

“…The STROBE checklist contains 22 numbered items, but some items have multiple subitems [35]. There is no differential weighting of items or subitems, and there is no hierarchy of item importance.…”

“…In total, there are 34 items that can be evaluated for each study. Under the supervision of a senior investigator (MG), two independent reviewers (NE, JN) learned to use the STROBE checklist by reviewing a published explanatory article and a published practical application guide [30,35]. The published application guide was used to define the criteria required to score each STROBE item as adequately reported [30,35].…”

“…Sensitivity analyses are secondary statistical calculations that examine uncertainties in the primary analyses, such as quantifying the impact of losses to follow-up or missing data on the study outcomes [35];…”