The BMJ最新文献

{"title":"Dealing with continuous variables and modelling non-linear associations in healthcare data: practical guide","authors":"Pedro Lopez-Ayala, Richard D Riley, Gary S Collins, Tobias Zimmermann","doi":"10.1136/bmj-2024-082440","DOIUrl":"https://doi.org/10.1136/bmj-2024-082440","url":null,"abstract":"Proper handling of continuous variables is crucial in healthcare research, for example, within regression modelling for descriptive, explanatory, or predictive purposes. However, inadequate methods are commonly used. This article highlights the importance of appropriately handling continuous variables, and illustrates the consequences of categorisation. This article also explains why assuming a linear relationship between the independent and dependent variable might be inappropriate, and describes how to use splines or fractional polynomials to model non-linear relationships. Continuous variables such as age, vital parameters, or biomarker concentrations are abundant in healthcare research. Whether the research aim is to describe (eg, whether age is associated with six month mortality after a diagnosis of covid-19), explain (eg, does the effect of a new cancer drug vary according to the value of a continuous biomarker), or predict (eg, does adding blood pressure to the model improve the prediction accuracy of risk for cardiovascular disease),1 researchers should appropriately model the association between independent and dependent variables. Researchers frequently encounter this challenge, for example, when fitting a regression model. But too often, the approaches used are inadequate, including submissions to The BMJ .2 In this article, we provide an overview of the current state of handling continuous variables in healthcare research. We discuss the drawbacks of categorising a continuous variable, and the potential limitations of assuming a linear relationship between independent and dependent variables. We discuss existing reviews of current practice and then outline two recommended approaches that allow for non-linear relationships: fractional polynomials345 and splines,678 with a particular focus on restricted cubic splines. Box 1 provides a list of key terms, and the key messages are illustrated throughout using the publicly available acute bacterial meningitis dataset,9 where we examine the association between levels of glucose in cerebrospinal fluid …","PeriodicalId":22388,"journal":{"name":"The BMJ","volume":"53 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144639690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Leng review: recommendations provide a constructive way forward","authors":"Gillian Leng","doi":"10.1136/bmj.r1478","DOIUrl":"https://doi.org/10.1136/bmj.r1478","url":null,"abstract":"After an extensive period of debate and examination of evidence about physician and anaesthesia associate roles, my review can provide clarity, says Gillian Leng It was a privilege to be asked by Wes Streeting, the secretary of state for health and social care, to review the safety and effectiveness of anaesthesia associates (AAs) and physician associates (PAs). It probably represents the biggest review of any staff group that has ever been conducted. It was evident early on that the longstanding, impassioned views on both sides of the debate would make navigating the task challenging. At the heart of the matter was that AA and PA roles are closer to that of doctors than any other professional, generating frustration, particularly among resident doctors. They raised concerns about PAs operating at unsafe levels, unsupported by adequate training, that took away their training opportunities, and also that—at the extreme—doctors were being quietly replaced by cheaper members of staff. The review has undertaken intensive investigation to consider safety and effectiveness and the surrounding problems.1 There was a comprehensive review of international literature, plus national data on patient safety, local …","PeriodicalId":22388,"journal":{"name":"The BMJ","volume":"29 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144639691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"What are the health risks of marrying cousins?","authors":"Katharine Lang","doi":"10.1136/bmj.r1453","DOIUrl":"https://doi.org/10.1136/bmj.r1453","url":null,"abstract":"","PeriodicalId":22388,"journal":{"name":"The BMJ","volume":"15 1","pages":"r1453"},"PeriodicalIF":0.0,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144645968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sixty seconds on . . . alcohol at football.","authors":"Gareth Iacobucci","doi":"10.1136/bmj.r1496","DOIUrl":"https://doi.org/10.1136/bmj.r1496","url":null,"abstract":"","PeriodicalId":22388,"journal":{"name":"The BMJ","volume":"84 1","pages":"r1496"},"PeriodicalIF":0.0,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144645976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Farewell, associates. Welcome back assistants","authors":"Trisha Greenhalgh, Martin McKee","doi":"10.1136/bmj.r1477","DOIUrl":"https://doi.org/10.1136/bmj.r1477","url":null,"abstract":"On 20 November 2024, Wes Streeting, the UK’s Secretary of State for Health and Social Care, commissioned Gillian Leng to undertake an independent review of physician associates and anaesthesia associates. The rationale, in his words, was that “…there are legitimate concerns over transparency for patients, scope of practice and the substituting of doctors. These concerns have been ignored for too long, leading to a toxic debate where physicians feel ignored and [physician associates] feel demoralised.” 1 Leng was asked to consider two main questions. Were these staff roles (as currently deployed in England) safe? Were they clinically effective? Today, less than eight months later, the 134 page Leng Review has been published.2 It draws on academic research from within and beyond the UK, as well as a survey of over 8000 healthcare staff and consultation with additional individuals and groups, including patients and the public. The review makes 18 recommendations, 12 of which relate directly or indirectly to patient safety. Physician associates, the review proposes, should be renamed “physician assistants.” They should be required to wear nationally standardised clothing, lanyards, and badges to distinguish them from doctors. They should not be allowed to see undifferentiated patients, nor should they be permitted to work in primary care until they have at least two years’ …","PeriodicalId":22388,"journal":{"name":"The BMJ","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144639988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Competing for a specialty training post feels like a high stakes game of musical chairs","authors":"Nikki Nabavi","doi":"10.1136/bmj.r1492","DOIUrl":"https://doi.org/10.1136/bmj.r1492","url":null,"abstract":"Doctors’ discontent with the training system is multifaceted and deep, says Nikki Nabavi Every year, thousands of doctors enter a high stakes game of musical chairs, competing for a shrinking pool of specialty training posts in a process that has little clarity or predictability. As a foundation doctor approaching the end of my first year of work, fears about this process loom over me as the application window for my cohort approaches this autumn. Most of my peers are opting not to apply to the next stage straight away. Their reasons are multifactorial, but the central problem remains that the current speciality training system in the UK is not fit for purpose. As medical organisations have highlighted, the bottleneck for specialty training posts is worsening.1 In 2024, some specialties reported competition ratios as high as 112 applicants for every one post, with even core surgical (5:1), internal medical (4:1), and psychiatry (9:1) training posts becoming increasingly oversubscribed.2 This is the result of several factors, including the increased popularity of taking time out of formal training programmes (so that more candidates apply in the following years),3 the gradual expansion of medical school …","PeriodicalId":22388,"journal":{"name":"The BMJ","volume":"23 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144639989","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Leng review offers \"pragmatic solution\" in attempt to heal rift between doctors and PAs.","authors":"Jacqui Wise","doi":"10.1136/bmj.r1482","DOIUrl":"https://doi.org/10.1136/bmj.r1482","url":null,"abstract":"","PeriodicalId":22388,"journal":{"name":"The BMJ","volume":"7 1","pages":"r1482"},"PeriodicalIF":0.0,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144645966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tom Dolphin: There is potential for many thousands of unemployed doctors.","authors":"Rebecca Coombes","doi":"10.1136/bmj.r1481","DOIUrl":"https://doi.org/10.1136/bmj.r1481","url":null,"abstract":"","PeriodicalId":22388,"journal":{"name":"The BMJ","volume":"24 1","pages":"r1481"},"PeriodicalIF":0.0,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144640129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physician associate debate: RCP councillor faces year's suspension after social media \"breaches\".","authors":"Kate Bowie","doi":"10.1136/bmj.r1487","DOIUrl":"https://doi.org/10.1136/bmj.r1487","url":null,"abstract":"","PeriodicalId":22388,"journal":{"name":"The BMJ","volume":"8 1","pages":"r1487"},"PeriodicalIF":0.0,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144640130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measles: Parents urged to vaccinate after child in Liverpool dies.","authors":"Kate Bowie","doi":"10.1136/bmj.r1475","DOIUrl":"https://doi.org/10.1136/bmj.r1475","url":null,"abstract":"","PeriodicalId":22388,"journal":{"name":"The BMJ","volume":"10 1","pages":"r1475"},"PeriodicalIF":0.0,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144640132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}