Abstract:
OBJECTIVE:To re-evaluate the causal effect of interpregnancy interval on adverse birth outcomes, on the basis that previous studies relying on between mother comparisons may have inadequately adjusted for confounding by maternal risk factors. DESIGN:Retrospective cohort study using conditional logistic regression (matching two intervals per mother so each mother acts as her own control) to model the incidence of adverse birth outcomes as a function of interpregnancy interval; additional unconditional logistic regression with adjustment for confounders enabled comparison with the unmatched design of previous studies. SETTING:Perth, Western Australia, 1980-2010. PARTICIPANTS:40 441 mothers who each delivered three liveborn singleton neonates. MAIN OUTCOME MEASURES:Preterm birth (<37 weeks), small for gestational age birth (<10th centile of birth weight by sex and gestational age), and low birth weight (<2500 g). RESULTS:Within mother analysis of interpregnancy intervals indicated a much weaker effect of short intervals on the odds of preterm birth and low birth weight compared with estimates generated using a traditional between mother analysis. The traditional unmatched design estimated an adjusted odds ratio for an interpregnancy interval of 0-5 months (relative to the reference category of 18-23 months) of 1.41 (95% confidence interval 1.31 to 1.51) for preterm birth, 1.26 (1.15 to 1.37) for low birth weight, and 0.98 (0.92 to 1.06) for small for gestational age birth. In comparison, the matched design showed a much weaker effect of short interpregnancy interval on preterm birth (odds ratio 1.07, 0.86 to 1.34) and low birth weight (1.03, 0.79 to 1.34), and the effect for small for gestational age birth remained small (1.08, 0.87 to 1.34). Both the unmatched and matched models estimated a high odds of small for gestational age birth and low birth weight for long interpregnancy intervals (longer than 59 months), but the estimated effect of long interpregnancy intervals on the odds of preterm birth was much weaker in the matched model than in the unmatched model. CONCLUSION:This study questions the causal effect of short interpregnancy intervals on adverse birth outcomes and points to the possibility of unmeasured or inadequately specified maternal factors in previous studies.
journal_name
BMJjournal_title
BMJ (Clinical research ed.)authors
Ball SJ,Pereira G,Jacoby P,de Klerk N,Stanley FJdoi
10.1136/bmj.g4333subject
Has Abstractpub_date
2014-07-23 00:00:00pages
g4333eissn
0959-8138issn
1756-1833journal_volume
349pub_type
杂志文章abstract:OBJECTIVES:To identify the genetic determinants of fracture risk and assess the role of 15 clinical risk factors on osteoporotic fracture risk. DESIGN:Meta-analysis of genome wide association studies (GWAS) and a two-sample mendelian randomisation approach. SETTING:25 cohorts from Europe, United States, east Asia, an...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章,meta分析
doi:10.1136/bmj.k3225
更新日期:2018-08-29 00:00:00
abstract::In July 1992 Dr Keith Mumby, a clinical ecologist, appeared before the professional conduct committee of the General Medical Council on five charges to do with his practice of clinical ecology. He was found guilty of two of the charges--touting for publicity and failing to give a patient adequate medical attention--an...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.306.6870.122
更新日期:1993-01-09 00:00:00
abstract:OBJECTIVES:To assess the incidence, time of day, and driver morbidity associated with vehicle accidents where the most likely cause was the driver falling asleep at the wheel. DESIGN:Two surveys were undertaken, in southwest England and the midlands, by using police databases or on the spot interviews. SUBJECTS:Drive...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.310.6979.565
更新日期:1995-03-04 00:00:00
abstract:OBJECTIVE:To determine whether genetic factors associated with established rheumatoid arthritis could, in combination with rheumatoid factor, predict the development of radiological erosions in patients with early symmetrical (rheumatoid-like) arthritis. DESIGN:Prospective study. SETTING:Teaching hospital, early arth...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.305.6866.1387
更新日期:1992-12-05 00:00:00
abstract::For an unprepared sexually active teenager the 1990s present a minefield of potential problems in addition to the most obvious problems of unplanned pregnancy and sexually transmitted disease. Promoting the importance of a healthy sexual and reproductive life to young people requires openness, better sex education, re...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.309.6957.786
更新日期:1994-09-24 00:00:00
abstract::The studySheppard JP, Stevens S, Stevens R, Martin U, Mant J, Hobbs R, McManus R. Benefits and harms of antihypertensive treatment in low-risk patients with mild hypertension.Published on 1 December 2018 JAMA Intern Med 2018;178:1626-34.This project was funded by a grant from the National Institute for Health Research...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.l571
更新日期:2019-02-15 00:00:00
abstract:OBJECTIVES:To gain insight into people's thoughts on stroke and to inform the development of educational strategies in the community. DESIGN:Focus group discussions: two groups of people who had a stroke and their carers, and two groups of members of the general public. SETTING:New South Wales, Australia. PARTICIPAN...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.324.7345.1065
更新日期:2002-05-04 00:00:00
abstract:OBJECTIVES:To investigate the association between contemporary combined hormonal contraceptives (including progestogen types in combined preparations and all progestogen-only products) and overall and specific types of ovarian cancer. DESIGN:Prospective, nationwide cohort study. SETTING:Denmark, 1995-2014. PARTICIPA...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.k3609
更新日期:2018-09-26 00:00:00
abstract::The Health of the Nation white paper set a target for 15% reduction in overall suicide rates by the year 2000. If the targets are to be achieved interventions must be identified which are of proved effectiveness. This paper examines the evidence on the available interventions and points of access to the population at ...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章,评审
doi:10.1136/bmj.308.6938.1227
更新日期:1994-05-07 00:00:00
abstract:OBJECTIVE:To determine whether short-term, oral low dose prednisolone (< or = 15 mg daily) is superior to placebo and non-steroidal anti-inflammatory drugs in patients with rheumatoid arthritis. DESIGN:Meta-analysis of randomised trials of oral corticosteroids compared with placebo or a non-steroidal anti-inflammatory...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章,meta分析
doi:10.1136/bmj.316.7134.811
更新日期:1998-03-14 00:00:00
abstract:OBJECTIVE:To determine cancer morbidity in members of the armed forces who took part in tests of chemical warfare agents from 1941 to 1989. DESIGN:Historical cohort study, with cohort members followed up to December 2004. DATA SOURCE:Archive of UK government research facility at Porton Down, UK military personnel rec...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.b655
更新日期:2009-03-24 00:00:00
abstract:OBJECTIVE:To determine if any excess of childhood leukaemia was associated with the large and increasing numbers of national military servicemen in 1949 and 1950, particularly in rural districts. This would be a further test of the hypothesis that childhood leukaemia can originate in an infection, the transmission of w...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.303.6814.1357
更新日期:1991-11-30 00:00:00
abstract:OBJECTIVE:To determine the efficacy of a probiotic drink containing Lactobacillus for the prevention of any diarrhoea associated with antibiotic use and that caused by Clostridium difficile. DESIGN:Randomised double blind placebo controlled study. PARTICIPANTS:135 hospital patients (mean age 74) taking antibiotics. E...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章,多中心研究,随机对照试验
doi:10.1136/bmj.39231.599815.55
更新日期:2007-07-14 00:00:00
abstract:OBJECTIVES:To identify the frequency with which antibiotics are prescribed in the absence of a documented indication in the ambulatory care setting, to quantify the potential effect on assessments of appropriateness of antibiotics, and to understand patient, provider, and visit level characteristics associated with ant...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章,多中心研究
doi:10.1136/bmj.l6461
更新日期:2019-12-11 00:00:00
abstract:OBJECTIVE:To determine the appropriateness of referrals from general practice to hospital outpatient departments. DESIGN:Prospective audit of referrals from a group practice over one year. SETTING:Six handed practice in a southern coastal town. SUBJECTS:All patients referred during the study period for whom a copy o...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.299.6701.722
更新日期:1989-09-16 00:00:00
abstract:OBJECTIVE:To determine the prevalence of sexually transmitted diseases in patients with normal and abnormal cervical smears. DESIGN:A prospective study of asymptomatic women with normal cervical smears attending their general practitioner and newly referred patients with abnormal smears attending a colposcopy clinic. ...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.302.6768.82
更新日期:1991-01-12 00:00:00
abstract:OBJECTIVE:To compare the efficacy of five probiotic preparations recommended to parents in the treatment of acute diarrhoea in children. Design Randomised controlled clinical trial in collaboration with family paediatricians over 12 months. SETTING:Primary care. PARTICIPANTS:Children aged 3-36 months visiting a famil...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章,随机对照试验
doi:10.1136/bmj.39272.581736.55
更新日期:2007-08-18 00:00:00
abstract:OBJECTIVES:To develop an easily applicable diagnostic scoring method to determine the presence of peptic ulcers in dyspeptic patients in a primary care setting; to evaluate whether Helicobacter pylori testing adds value to history taking. DESIGN:Cross sectional study. SETTING:General practitioners' offices in the Utr...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.323.7304.71
更新日期:2001-07-14 00:00:00
abstract:OBJECTIVE:To describe and quantify patterns of injury from antipersonnel mines in terms of distribution of injury, drain on surgical resources, and residual disability. DESIGN:Retrospective analysis. SETTING:Two hospitals for patients injured in war. SUBJECTS:757 patients with injuries from antipersonnel mines. MAI...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.303.6816.1509
更新日期:1991-12-14 00:00:00
abstract:OBJECTIVE:To investigate estimation of calorie (energy) content of meals from fast food restaurants in adults, adolescents, and school age children. DESIGN:Cross sectional study of repeated visits to fast food restaurant chains. SETTING:89 fast food restaurants in four cities in New England, United States: McDonald's...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.f2907
更新日期:2013-05-23 00:00:00
abstract:OBJECTIVE:To investigate the effect of watching different types of video on energy expenditure. DESIGN:Randomised study assessing a "pleasant," an "amusing," an "exciting," and no video film clips. SUBJECTS:12 volunteers who did not know the purpose of the study. MAIN OUTCOME MEASURES:Changes in energy expenditure, ...
journal_title:BMJ (Clinical research ed.)
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1136/bmj.311.7021.1664
更新日期:1995-12-23 00:00:00
abstract:OBJECTIVE:To compare the risk of detention under the Mental Health Act 1983 in a representative group of people with psychotic disorders from different ethnic groups. SETTING:Two defined geographical areas in south London. DESIGN:Annual period prevalent cases of psychosis were identified in 1993 in the study areas fr...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.312.7030.533
更新日期:1996-03-02 00:00:00
abstract:OBJECTIVE:To assess the cost-effectiveness of low dose statins for primary prevention of vascular disease, incorporating current prices, non-adherence (reduced clinical efficacy while maintaining healthcare costs), and the results of the recently published JUPITER trial. DESIGN:Cost-effectiveness analysis using a Mark...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.d1672
更新日期:2011-03-30 00:00:00
abstract::Ruben Meerman and Andrew Brown explain why the answer might not be what you expect. ...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.g7257
更新日期:2014-12-16 00:00:00
abstract:OBJECTIVE:To examine the associations between neuraxial anaesthesia or general anaesthesia and clinical outcomes, length of hospital stay, and readmission in adults undergoing lower limb revascularisation surgery. DESIGN:Comparative effectiveness study using linked, validated, population based databases. SETTING:Onta...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.m4104
更新日期:2020-11-25 00:00:00
abstract::Current services for those with mental disorders show two trends. Psychiatric services are becoming concentrated on the care of those with "severe mental illness," largely (but unjustifiably) synonymous with chronic psychosis. The retreat of psychiatry from the care of those with non-psychotic mental disorders has hel...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.313.7050.158
更新日期:1996-07-20 00:00:00
abstract::The studies reviewed here show that the duration and severity of individual episodes of back pain can be lessened, reducing recurrences and their cost in terms of suffering and lost work. Frank examines differential diagnosis; acute, chronic, and intractable pain; and service implications. Modern management emphasises...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章,评审
doi:10.1136/bmj.306.6882.901
更新日期:1993-04-03 00:00:00
abstract:OBJECTIVES:To calculate socioeconomic and health status measures for the primary care groups in London and to examine the association between these measures and hospital admission rates. DESIGN:Cross sectional study. SETTING:66 primary care groups in London, total list size 8.0 million people. MAIN OUTCOME MEASURES:...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.321.7268.1057
更新日期:2000-10-28 00:00:00
abstract:OBJECTIVE:To assess the implementation of action protocols dictated by antenatal risk factors noted at the initial (booking) antenatal visit. DESIGN:Retrospective study of 2000 women delivered between 1 March 1990 and 29 March 1991. SETTING:Maternity department of a district general hospital supporting a multiethnic ...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.305.6863.1184
更新日期:1992-11-14 00:00:00
abstract::The instrument through which a commissioner purchases health services from a provider is, as in other walks of life, a contract, so considerable importance has been attached by the NHS Executive to the contracting mechanism. A contract should in theory influence the quality of the service provided, but they are in man...
journal_title:BMJ (Clinical research ed.)
pub_type: 杂志文章
doi:10.1136/bmj.313.7055.477
更新日期:1996-08-24 00:00:00