Objective To examine whether maternal opioid treatment after delivery is associated with an increased risk of adverse infant outcomes. Design Population based cohort study. Setting Ontario, Canada. Participants 865 691 mother-infant pairs discharged from hospital alive within seven days of delivery from 1 September 2012 to 31 March 2020. Each mother who filled an opioid prescription within seven days

Objective To compare the effectiveness of the BNT162b2 mRNA (Pfizer-BioNTech) and mRNA-1273 (Moderna) covid-19 vaccines during the booster programme in England. Design Matched cohort study, emulating a comparative effectiveness trial. Setting Linked primary care, hospital, and covid-19 surveillance records available within the OpenSAFELY-TPP research platform, covering a period when the SARS-CoV-2

Objective To systematically review and perform a meta-analysis of radiation associated risks of cardiovascular disease in all groups exposed to radiation with individual radiation dose estimates. Design Systematic review and meta-analysis. Main outcome measures Excess relative risk per unit dose (Gy), estimated by restricted maximum likelihood methods. Data sources PubMed and Medline, Embase, Scopus

Objective To synthesise results of mental health outcomes in cohorts before and during the covid-19 pandemic. Design Systematic review. Data sources Medline, PsycINFO, CINAHL, Embase, Web of Science, China National Knowledge Infrastructure, Wanfang, medRxiv, and Open Science Framework Preprints. Eligibility criteria for selecting studies Studies comparing general mental health, anxiety symptoms, or

Objective To emulate a randomized target trial to estimate the association between the antiviral drug molnupiravir and hospital admission or death in adults with SARS-CoV-2 infection in the community during the omicron predominant era who were at high risk of progression to severe covid-19. Design Emulation of a randomized target trial using electronic health records. Setting US Department of Veterans

Objective To estimate US public investment in the development of mRNA covid-19 vaccines. Design Retrospective cohort study. Setting Publicly funded science from January 1985 to March 2022. Data sources National Institutes of Health (NIH) Report Portfolio Online Reporting Tool Expenditures and Results (RePORTER) and other public databases. Government funded grants were scored as directly, indirectly

Objective To assess inequities in mortality by race and sex for eight common surgical procedures (elective and non-elective) across specialties in the United States. Design Retrospective cohort study. Setting US, 2016-18. Participants 1 868 036 Black and White Medicare beneficiaries aged 65-99 years undergoing one of eight common surgeries: repair of abdominal aortic aneurysm, appendectomy, cholecystectomy

Objective To evaluate whether antibiotic prescribing for suspected urinary tract infections in frail older adults can be reduced through a multifaceted antibiotic stewardship intervention. Design Pragmatic, parallel, cluster randomised controlled trial, with a five month baseline period and a seven month follow-up period. Setting 38 clusters consisting of one or more general practices (n=43) and older

Objectives To review available health and nutrition claims for infant formula products in multiple countries and to evaluate the validity of the evidence used for substantiation of claims. Design International cross sectional survey. Setting Public facing and healthcare professional facing company owned or company managed formula industry websites providing information about products marketed for healthy

Objective To estimate the effectiveness, cost effectiveness (to be reported elsewhere), and safety of pharmacy independent prescribers in care homes. Design Cluster randomised controlled trial, with clusters based on triads of a pharmacist independent prescriber, a general practice, and one to three associated care homes. Setting Care homes across England, Scotland, and Northern Ireland, their associated

Objective To estimate the effectiveness of maternal mRNA covid-19 vaccination during pregnancy against delta and omicron severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection and hospital admission in infants. Design Test negative design study. Setting Community and hospital testing in Ontario, Canada. Participants Infants younger than six months of age, born between 7 May 2021 and

Objectives To address whether sparing the medial retropharyngeal lymph node (MRLN) region from elective irradiation volume provides non-inferior local relapse-free survival versus standard radiotherapy in patients with nasopharyngeal carcinoma. Design Open-label, non-inferiority, multicentre, randomised, phase 3 trial. Setting Three Chinese hospitals between 20 November 2017 and 3 December 2018. Participants

Objective To provide a comprehensive overview of the efficacy, safety, and tolerability of antidepressants for pain according to condition. Design Overview of systematic reviews. Data sources PubMed, Embase, PsycINFO, and the Cochrane Central Register of Controlled Trials from inception to 20 June 2022. Eligibility criteria for selecting studies Systematic reviews comparing any antidepressant with

Objective To examine the associations between five major adverse pregnancy outcomes and long term risks of ischemic heart disease in mothers. Design National cohort study. Setting Sweden. Participants All 2 195 266 women with a first singleton delivery in Sweden during 1973-2015. Main outcome measures The main outcome measure was incidence of ischemic heart disease from delivery to 2018, identified

Objective To identify an optimal lifestyle profile to protect against memory loss in older individuals. Design Population based, prospective cohort study. Setting Participants from areas representative of the north, south, and west of China. Participants Individuals aged 60 years or older who had normal cognition and underwent apolipoprotein E (APOE) genotyping at baseline in 2009. Main outcome measures

Objective To investigate whether monitoring of cerebral tissue oxygen saturation using near infrared spectroscopy in addition to routine monitoring combined with defined treatment guidelines during immediate transition and resuscitation increases survival without cerebral injury of premature infants compared with standard care alone. Design Multicentre, multinational, randomised controlled phase 3

Objective To assess the prospective associations of circulating levels of omega 3 polyunsaturated fatty acid (n-3 PUFA) biomarkers (including plant derived α linolenic acid and seafood derived eicosapentaenoic acid, docosapentaenoic acid, and docosahexaenoic acid) with incident chronic kidney disease (CKD). Design Pooled analysis. Data sources A consortium of 19 studies from 12 countries identified

Objective To investigate the association between gestational age at birth and cognitive outcomes in adolescence. Design Nationwide population based full sibling cohort study. Setting Denmark. Participants 1.2 million children born between 1 January 1986 and 31 December 2003, of whom 792 724 had one or more full siblings born in the same period. Main outcome measures Scores in written language (Danish)

Objective To assess the recent trends in prevalence and management of hypertension in China, nationally and by population subgroups. Design Six rounds of a national survey, China. Setting China Chronic Disease and Risk Factors Surveillance, 2004-18. Participants 642 523 community dwelling adults aged 18-69 years (30 501 in 2004, 47 353 in 2007, 90 491 in 2010, 156 836 in 2013, 162 293 in 2015, and

Objectives To determine the clinical sequelae of long covid for a year after infection in patients with mild disease and to evaluate its association with age, sex, SARS-CoV-2 variants, and vaccination status. Design Retrospective nationwide cohort study. Setting Electronic medical records from an Israeli nationwide healthcare organisation. Population 1 913 234 Maccabi Healthcare Services members of

Objective To examine labour market participation and retirement among patients with stroke and matched people in the general population according to stroke subtype. Design Nationwide, population based, matched cohort study. Setting Danish Stroke Registry, covering all Danish hospitals, and other nationwide registries (2005-18). Participants Patients (aged 18-60 years and active in the labour market)

This article discusses the use of indirect calorimetry for the measurement of human energy expenditure. Quantification of energy expenditure during low efficiency walking (as depicted in the Monty Python sketch The Ministry of Silly Walks) is presented as an example of how physical activity recommendations could be met by exchanging ~11 minutes per day of normal walking with low efficiency walking—without

Objective To compare the rate of energy expenditure of low efficiency walking with high efficiency walking. Design Laboratory based experimental study. Setting United States. Participants 13 healthy adults (six women, seven men) with no known gait disorder, mean (±standard deviation) age 34.2±16.1 years, height 174.2±12.6 cm, weight 78.2±22.5 kg, and body mass index 25.6±6.0. Intervention Participants

Objectives To assess whether male elite football players are at increased risk of alcohol related disorders compared with men from the general population, and whether such an increased risk would vary on the basis of calendar year of the first playing season in the top tier of competition, age, career length, and goal scoring abilities. Design Nationwide cohort study. Setting Sweden, 1924-2020. Participants

Objective To determine whether an artificial intelligence candidate could pass the rapid (radiographic) reporting component of the Fellowship of the Royal College of Radiologists (FRCR) examination. Design Prospective multi-reader diagnostic accuracy study. Setting United Kingdom. Participants One artificial intelligence candidate (Smarturgences, Milvue) and 26 radiologists who had passed the FRCR

Objective To evaluate, using an online non-probability sample, the beliefs about and attitudes towards cancer prevention of people professing vaccination scepticism or conspiracy theories. Design Cross sectional survey. Setting Data collected mainly from ForoCoches (a well known Spanish forum) and other platforms, including Reddit (English), 4Chan (English), HispaChan (Spanish), and a Spanish language

Objectives To examine the recruitment, retention, and preliminary effects of a Christmas themed physical activity intervention designed to increase participation in physical activity and decrease sedentary behaviour in inactive adults. Design Pilot randomised controlled trial. Setting Recruitment from social medial platforms, workplaces, and community groups in the UK. Participants 107 inactive adults

Objectives To identify the time required to achieve optimal palatability of a cup of tea without risk of harm (oral scalding) using the resources available in a standard hospital staff room, and to identify the best accompanying biscuit for nutritional content, crunchiness, and integrity when dunking. Design Prospective, non-masked, biscuit based, comparative study. Setting Staff room in the surgery

Objective To investigate the typing skills of healthcare professionals. Design Cross sectional study. Setting Two large tertiary medical centres in Amsterdam, the Netherlands. Participants 2690 hospital employees working in patient care, research, or medical education. Main outcome measures Participants completed a custom built, web based, Santa themed, typing test in 60 seconds and filled out an associated

Objective To evaluate the ability of The BMJ editors to predict the number of times submitted research manuscripts will be cited. Design Cohort study. Setting Manuscripts submitted to The BMJ , reviewed, and subsequently scheduled for discussion at a prepublication meeting between 27 August 2015 and 29 December 2016. Participants 10 BMJ research team editors. Main outcome measures Reviewed manuscripts

Objective To determine the efficacy and safety of awake prone positioning versus usual care in non-intubated adults with hypoxemic respiratory failure due to covid-19. Design Systematic review with frequentist and bayesian meta-analyses. Study eligibility Randomized trials comparing awake prone positioning versus usual care in adults with covid-19 related hypoxemic respiratory failure. Information

Objective To estimate the global burden of type 2 diabetes in adolescents and young adults (aged 15-39 years) from 1990 to 2019. Design Systematic analysis. Data source Global Burden of Disease Study 2019. Participants aged 15-39 years from 204 countries and territories, 1990-2019. Main outcomes measures Age standardised incidence rate, age standardised disability adjusted life years (DALY) rate, and

Objective To determine the effectiveness of two online behavioural interventions, one for parents and carers and one for young people, to support eczema self-management. Design Two independent, pragmatic, parallel group, unmasked, randomised controlled trials. Setting 98 general practices in England. Participants Parents and carers of children (0-12 years) with eczema (trial 1) and young people (13-25

Objective To examine whether supraphysiological oxygen administration during surgery is associated with lower or higher postoperative kidney, heart, and lung injury. Design Observational cohort study. Setting 42 medical centers across the United States participating in the Multicenter Perioperative Outcomes Group data registry. Participants Adult patients undergoing surgical procedures ≥120 minutes’

Objective To estimate the effectiveness of a two dose vaccine schedule (mRNA-1273, BNT162b2, and BBIBP-CorV) against SARS-CoV-2 infection and covid-19 related death and short term waning of immunity in children (3-11 years old) and adolescents (12-17 years old) during periods of delta and omicron variant predominance in Argentina. Design Test negative, case-control study. Setting Database of the National

Objectives To describe retracted papers originating from paper mills, including their characteristics, visibility, and impact over time, and the journals in which they were published. Design Cross sectional study. Setting The Retraction Watch database was used for identification of retracted papers from paper mills, Web of Science was used for the total number of published papers, and data from Journal

Interventions in emergencies such as the covid-19 pandemic may need rapid supporting evidence. Randomised trials in these situations are often impractical to design or deliver. One technique for estimating the causal effect of an intervention using observational data is the synthetic control method. This article outlines the method and its assumptions, best practice interpretation, and application

Objective To analyse the impact of voluntary rapid testing for SARS-CoV-2 antigen in Liverpool city on covid-19 related hospital admissions. Design Synthetic control analysis comparing hospital admissions for small areas in the intervention population with a group of control areas weighted to be similar for past covid-19 related hospital admission rates and sociodemographic factors. Setting Liverpool

Objective To compare two different treatment durations of rivaroxaban in patients with symptomatic isolated distal deep vein thrombosis (DVT). Design Randomised, double blind, placebo controlled clinical trial. Setting 28 outpatient clinics specialising in venous thromboembolism. Participants 402 adults (≥18 years) with symptomatic isolated distal DVT. Interventions After receiving standard dose rivaroxaban

Objectives To examine changes in completeness of reporting and frequency of sharing data, analytical code, and other review materials in systematic reviews over time; and factors associated with these changes. Design Cross sectional meta-research study. Population Random sample of 300 systematic reviews with meta-analysis of aggregate data on the effects of a health, social, behavioural, or educational

Objective To determine whether disrupting the renin angiotensin system with angiotensin receptor blockers will improve clinical outcomes in people with covid-19. Design CLARITY was a pragmatic, adaptive, multicentre, phase 3, randomised controlled trial. Setting 17 hospital sites in India and Australia. Participants Participants were at least 18 years old, previously untreated with angiotensin receptor

Objective To compare maternal mortality in eight countries with enhanced surveillance systems. Design Descriptive multicountry population based study. Setting Eight countries with permanent surveillance systems using enhanced methods to identify, document, and review maternal deaths. The most recent available aggregated maternal mortality data were collected for three year periods for France, Italy

Objective To compare the effectiveness of sotrovimab (a neutralising monoclonal antibody) with molnupiravir (an antiviral) in preventing severe outcomes of covid-19 in adult patients infected with SARS-CoV-2 in the community and at high risk of severe outcomes from covid-19. Design Observational cohort study with the OpenSAFELY platform. Setting With the approval of NHS England, a real world cohort

Objective To evaluate the benefit of combining polygenic risk scores with the QCancer-10 (colorectal cancer) prediction model for non-genetic risk to identify people at highest risk of colorectal cancer. Design Population based cohort study. Setting Data from the UK Biobank study, collected between March 2006 and July 2010. Participants 434 587 individuals with complete data for genetics and QCancer-10

Objective To develop and externally validate the STRAtifying Treatments In the multi-morbid Frail elderlY (STRATIFY)-Falls clinical prediction model to identify the risk of hospital admission or death from a fall in patients with an indication for antihypertensive treatment. Design Retrospective cohort study. Setting Primary care data from electronic health records contained within the UK Clinical

Objective To analyse the transmission dynamics of the monkeypox outbreak in the UK, declared a Public Health Emergency of International Concern in July 2022. Design Contact tracing study, linking data on case-contact pairs and on probable exposure dates. Setting Case questionnaires from the UK Health Security Agency (UKHSA), United Kingdom. Participants 2746 people with polymerase chain reaction confirmed

Objective To investigate whether oral antimicrobial prophylaxis as an adjunct to intravenous antibiotic prophylaxis reduces surgical site infections after elective colorectal surgery. Design Multicentre, randomised, double blind, placebo controlled trial. Setting 11 university and non-university hospitals in France between 25 May 2016 and 8 August 2019. Participants 926 adults scheduled for elective

Objectives To determine whether patient reported outcomes improve after single stage versus two stage revision surgery for prosthetic joint infection of the hip, and to determine the cost effectiveness of these procedures. Design Pragmatic, parallel group, open label, randomised controlled trial. Setting High volume tertiary referral centres or orthopaedic units in the UK (n=12) and in Sweden (n=3)

Objective To determine whether the use of glucagon-like peptide 1 (GLP-1) receptor agonists, dipeptidyl peptidase 4 (DPP-4) inhibitors, and sodium-glucose co-transporter-2 (SGLT-2) inhibitors, separately, is associated with a decreased risk of exacerbations of chronic obstructive pulmonary disease among patients with chronic obstructive pulmonary disease and type 2 diabetes. Design Population based

Objective To quantify the comparative risk of thrombosis with thrombocytopenia syndrome or thromboembolic events associated with use of adenovirus based covid-19 vaccines versus mRNA based covid-19 vaccines. Design International network cohort study. Setting Routinely collected health data from contributing datasets in France, Germany, the Netherlands, Spain, the UK, and the US. Participants Adults

Objective To determine the effect of integrated and concurrent delivery of health, nutrition, water, sanitation and hygiene (WaSH), and psychosocial care interventions during the preconception period alone, during pregnancy and early childhood, and throughout preconception, pregnancy, and early childhood on birth outcomes and linear growth at 24 months of age compared with routine care. Design Individually

Objective To evaluate long term outcomes (reintervention and late rupture of abdominal aortic aneurysm) of aortic endografts in real world practice using linked registry claims data. Design Observational surveillance study. Setting 282 centers in the Vascular Quality Initiative Registry linked to United States Medicare claims (2003-18). Participants 20 489 patients treated with four device types used

Objective To examine the association of maternal hypertensive disorder of pregnancy (HDP) with overall and cause specific mortality in offspring from birth to young adulthood. Design Nationwide population based cohort study. Setting Danish national health registers. Participants All 2 437 718 individuals live born in Denmark, 1978-2018, with follow-up from date of birth until date of death, emigration

Objective To examine effectiveness, cost effectiveness, generalisability, and acceptability of financial incentives for smoking cessation during pregnancy in addition to variously organised UK stop smoking services. Design Pragmatic, multicentre, single blinded, phase 3, randomised controlled trial (Cessation in Pregnancy Incentives Trial phase 3 (CPIT III)). Setting Seven UK stop smoking services

Objective To assess the comparative effectiveness of computed tomography and invasive coronary angiography in women and men with stable chest pain suspected to be caused by coronary artery disease. Design Prospective, multicentre, randomised pragmatic trial. Setting Hospitals at 26 sites in 16 European countries. Participants 2002 (56.2%) women and 1559 (43.8%) men (total of 3561 patients) with suspected

Objectives To describe symptoms and symptom clusters of post-covid syndrome six to 12 months after acute infection, describe risk factors, and examine the association of symptom clusters with general health and working capacity. Design Population based, cross sectional study Setting Adults aged 18-65 years with confirmed SARS-CoV-2 infection between October 2020 and March 2021 notified to health authorities

Objective To compare the effectiveness of a primary covid-19 vaccine series plus booster doses with a primary series alone for the prevention of hospital admission with omicron related covid-19 in the United States. Design Multicenter observational case-control study with a test negative design. Setting Hospitals in 18 US states. Participants 4760 adults admitted to one of 21 hospitals with acute respiratory

Objective To assess whether maternal ultra-processed food intake during peripregnancy and during the child rearing period is associated with offspring risk of overweight or obesity during childhood and adolescence. Design Population based prospective cohort study. Setting The Nurses’ Health Study II (NHSII) and the Growing Up Today Study (GUTS I and II) in the United States. Participants 19 958 mother-child

Objective To characterize potential drug safety signals identified from the US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS), from 2008 to 2019, to determine how often these signals resulted in regulatory action by the FDA and whether these actions were corroborated by published research findings or public assessments by the Sentinel Initiative. Design Cross sectional study

Objective To evaluate the association between initiation of fluoroquinolones and hospital admission or emergency department visit for suicidality. Design Population based cohort study. Setting IBM MarketScan database, USA. Participants 2 756 268 adults (≥18 years) who initiated an oral fluoroquinolone (ciprofloxacin, levofloxacin, moxifloxacin, gemifloxacin, ofloxacin, gatifloxacin, norfloxacin, lomefloxacin