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1.
Pediatr Obes ; : e12618, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32026653

RESUMO

BACKGROUND: Childhood obesity is a significant global problem. Childhood obesity prevention interventions may be more effective when started very early in life before metabolic and behavioural patterns are established. METHODS AND FINDINGS: A prospectively planned, individual participant data meta-analysis of four randomized controlled trials. Participants were first-time mothers of term infants. Trial interventions commenced during pregnancy or early infancy and comprised education and support delivered via group sessions and/or home visits. Control group families accessed existing local well-child health care. The primary outcome was body mass index (BMI) z score at 18 to 24 months; 2196 mother-child dyads were available for analysis. Intervention children had lower BMI z scores at 18 to 24 months than control children (-0.12 adjusted mean; 95% confidence interval, -0.22 to -0.02, P = .017). There was some evidence that the BMI z score reduction was greater in settings with limited well-child health care programmes (interaction P value = .03). Improvements were also detected in television viewing time, feeding practices, and breastfeeding duration. CONCLUSIONS: Parent-focused intervention programmes that commence by early infancy and which aim to establish a trajectory of healthy lifestyle behaviours produced a modest but statistically significant reduction in BMI z score, which if replicated on a wider scale may have important public health implications.

2.
Res Synth Methods ; 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31901013

RESUMO

The CONSORT Statement says that data-driven early stopping of a clinical trial is likely to weaken the inferences that can be drawn from the trial. The GRADE guidelines go further, saying that early stopping is a study limitation that carries the risk of bias, and recommending sensitivity analyses in which trials stopped early are omitted from evidence synthesis. Despite extensive debate in the literature over these issues, the existence of clear recommendations in high profile guidelines makes it inevitable that systematic reviewers will consider sensitivity analyses investigating the impact of early stopping. The purpose of this article is to assess methodologies for conducting such sensitivity analyses, and to make recommendations about how the guidelines should be interpreted. We begin with a clarifying overview of the impacts of early stopping on treatment effect estimation in single studies and meta-analyses. We then warn against naive approaches for conducting sensitivity analyses, including simply omitting trials stopped early from meta-analyses. This approach underestimates treatment effects, which may have serious implications if cost-effectiveness analyses determine whether treatments are made widely available. Instead, we discuss two unbiased approaches to sensitivity analysis, one of which is straightforward but statistically inefficient, and the other of which achieves greater statistical efficiency by making use of recent methodological developments in the analysis of clinical trials. We end with recommendations for interpreting: (a) the CONSORT Statement on reporting of reasons for early stopping, and (b) the GRADE guidelines on sensitivity analyses assessing the impact of early stopping.

3.
BMC Pregnancy Childbirth ; 20(1): 23, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31906891

RESUMO

BACKGROUND: Guidelines recommend identifying in early pregnancy women at elevated risk of pre-eclampsia. The aim of this study was to develop and validate a pre-eclampsia risk prediction model for nulliparous women attending routine antenatal care "the Western Sydney (WS) model"; and to compare its performance with the National Institute of Health and Care Excellence (NICE) risk factor-list approach for classifying women as high-risk. METHODS: This retrospective cohort study included all nulliparous women who gave birth in three public hospitals in the Western-Sydney-Local-Health-District, Australia 2011-2014. Using births from 2011 to 2012, multivariable logistic regression incorporated established maternal risk factors to develop and internally validate the WS model. The WS model was then externally validated using births from 2013 to 2014, assessing its discrimination and calibration. We fitted the final WS model for all births from 2011 to 2014, and compared its accuracy in predicting pre-eclampsia with the NICE approach. RESULTS: Among 12,395 births to nulliparous women in 2011-2014, there were 293 (2.4%) pre-eclampsia events. The WS model included: maternal age, body mass index, ethnicity, multiple pregnancy, family history of pre-eclampsia, autoimmune disease, chronic hypertension and chronic renal disease. In the validation sample (6201 births), the model c-statistic was 0.70 (95% confidence interval 0.65-0.75). The observed:expected ratio for pre-eclampsia was 0.91, with a Hosmer-Lemeshow goodness-of-fit test p-value of 0.20. In the entire study sample of 12,395 births, 374 (3.0%) women had a WS model-estimated pre-eclampsia risk ≥8%, the pre-specified risk-threshold for considering aspirin prophylaxis. Of these, 54 (14.4%) developed pre-eclampsia (sensitivity 18% (14-23), specificity 97% (97-98)). Using the NICE approach, 1173 (9.5%) women were classified as high-risk, of which 107 (9.1%) developed pre-eclampsia (sensitivity 37% (31-42), specificity 91% (91-92)). The final model showed similar accuracy to the NICE approach when using lower risk-threshold of ≥4% to classify women as high-risk for pre-eclampsia. CONCLUSION: The WS risk model that combines readily-available maternal characteristics achieved modest performance for prediction of pre-eclampsia in nulliparous women. The model did not outperform the NICE approach, but has the advantage of providing individualised absolute risk estimates, to assist with counselling, inform decisions for further testing, and consideration of aspirin prophylaxis.

4.
Cochrane Database Syst Rev ; 2019(10)2019 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684684

RESUMO

BACKGROUND: Pre-eclampsia is associated with deficient intravascular production of prostacyclin, a vasodilator, and excessive production of thromboxane, a vasoconstrictor and stimulant of platelet aggregation. These observations led to the hypotheses that antiplatelet agents, low-dose aspirin in particular, might prevent or delay development of pre-eclampsia. OBJECTIVES: To assess the effectiveness and safety of antiplatelet agents, such as aspirin and dipyridamole, when given to women at risk of developing pre-eclampsia. SEARCH METHODS: For this update, we searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (30 March 2018), and reference lists of retrieved studies. We updated the search in September 2019 and added the results to the awaiting classification section of the review. SELECTION CRITERIA: All randomised trials comparing antiplatelet agents with either placebo or no antiplatelet agent were included. Studies only published in abstract format were eligible for inclusion if sufficient information was available. We would have included cluster-randomised trials in the analyses along with individually-randomised trials, if any had been identified in our search strategy. Quasi-random studies were excluded. Participants were pregnant women at risk of developing pre-eclampsia. Interventions were administration of an antiplatelet agent (such as low-dose aspirin or dipyridamole), comparisons were either placebo or no antiplatelet. DATA COLLECTION AND ANALYSIS: Two review authors assessed trials for inclusion and extracted data independently. For binary outcomes, we calculated risk ratio (RR) and its 95% confidence interval (CI), on an intention-to-treat basis. For this update we incorporated individual participant data (IPD) from trials with this available, alongside aggregate data (AD) from trials where it was not, in order to enable reliable subgroup analyses and inclusion of two key new outcomes. We assessed risk of bias for included studies and created a 'Summary of findings' table using GRADE. MAIN RESULTS: Seventy-seven trials (40,249 women, and their babies) were included, although three trials (relating to 233 women) did not contribute data to the meta-analysis. Nine of the trials contributing data were large (> 1000 women recruited), accounting for 80% of women recruited. Although the trials took place in a wide range of countries, all of the nine large trials involved only women in high-income and/or upper middle-income countries. IPD were available for 36 trials (34,514 women), including all but one of the large trials. Low-dose aspirin alone was the intervention in all the large trials, and most trials overall. Dose in the large trials was 50 mg (1 trial, 1106 women), 60 mg (5 trials, 22,322 women), 75mg (1 trial, 3697 women) 100 mg (1 trial, 3294 women) and 150 mg (1 trial, 1776 women). Most studies were either low risk of bias or unclear risk of bias; and the large trials were all low risk of bas. Antiplatelet agents versus placebo/no treatment The use of antiplatelet agents reduced the risk of proteinuric pre-eclampsia by 18% (36,716 women, 60 trials, RR 0.82, 95% CI 0.77 to 0.88; high-quality evidence), number needed to treat for one women to benefit (NNTB) 61 (95% CI 45 to 92). There was a small (9%) reduction in the RR for preterm birth <37 weeks (35,212 women, 47 trials; RR 0.91, 95% CI 0.87 to 0.95, high-quality evidence), NNTB 61 (95% CI 42 to 114), and a 14% reduction infetal deaths, neonatal deaths or death before hospital discharge (35,391 babies, 52 trials; RR 0.85, 95% CI 0.76 to 0.95; high-quality evidence), NNTB 197 (95% CI 115 to 681). Antiplatelet agents slightly reduced the risk of small-for-gestational age babies (35,761 babies, 50 trials; RR 0.84, 95% CI 0.76 to 0.92; high-quality evidence), NNTB 146 (95% CI 90 to 386), and pregnancies with serious adverse outcome (a composite outcome including maternal death, baby death, pre-eclampsia, small-for-gestational age, and preterm birth) (RR 0.90, 95% CI 0.85 to 0.96; 17,382 women; 13 trials, high-quality evidence), NNTB 54 (95% CI 34 to 132). Antiplatelet agents probably slightly increase postpartum haemorrhage > 500 mL (23,769 women, 19 trials; RR 1.06, 95% CI 1.00 to 1.12; moderate-quality evidence due to clinical heterogeneity), and they probably marginally increase the risk of placental abruption, although for this outcome the evidence was downgraded due to a wide confidence interval including the possibility of no effect (30,775 women; 29 trials; RR 1.21, 95% CI 0.95 to 1.54; moderate-quality evidence). Data from two large trials which assessed children at aged 18 months (including results from over 5000 children), did not identify clear differences in development between the two groups. AUTHORS' CONCLUSIONS: Administering low-dose aspirin to pregnant women led to small-to-moderate benefits, including reductions in pre-eclampsia (16 fewer per 1000 women treated), preterm birth (16 fewer per 1000 treated), the baby being born small-for-gestational age (seven fewer per 1000 treated) and fetal or neonatal death (five fewer per 1000 treated). Overall, administering antiplatelet agents to 1000 women led to 20 fewer pregnancies with serious adverse outcomes. The quality of evidence for all these outcomes was high. Aspirin probably slightly increased the risk of postpartum haemorrhage of more than 500 mL, however, the quality of evidence for this outcome was downgraded to moderate, due to concerns of clinical heterogeneity in measurements of blood loss. Antiplatelet agents probably marginally increase placental abruption, but the quality of the evidence was downgraded to moderate due to low event numbers and thus wide 95% CI. Overall, antiplatelet agents improved outcomes, and at these doses appear to be safe. Identifying women who are most likely to respond to low-dose aspirin would improve targeting of treatment. As almost all the women in this review were recruited to the trials after 12 weeks' gestation, it is unclear whether starting treatment before 12 weeks' would have additional benefits without any increase in adverse effects. While there was some indication that higher doses of aspirin would be more effective, further studies would be warranted to examine this.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31583696

RESUMO

BACKGROUND: Rates of pre-eclampsia vary between countries and certain ethnic groups. However, there is limited evidence about the impact of ethnicity on risk of pre-eclampsia, beyond established clinical risk factors. AIMS: To assess the association between ethnicity and pre-eclampsia in Australia's diverse multi-ethnic population. MATERIALS AND METHODS: We conducted a retrospective cohort study using the ObstetriX database. We included all women with a birth between January 2011 and December 2014, at Auburn, Blacktown/Mount-Druitt and Westmead Hospitals in the Western Sydney Local Health District. We estimated the pre-eclampsia rate overall, and by maternal ethnic group, defined by country of birth and primary language. We developed multivariable logistic regression models to estimate odds ratios (OR) and 95% confidence intervals (CIs) for pre-eclampsia, adjusting for maternal age, body mass index, autoimmune disease, chronic hypertension, chronic renal disease, diabetes mellitus (type 1 or 2), and multiple pregnancy. A secondary analysis was restricted to nulliparous women. RESULTS: There were 40 824 women evaluated, including 12 743 nulliparous women. Of these, 1448 (3.5%) developed pre-eclampsia (range: Australian/New Zealand-born English speakers 735/15 422 (4.8%); North-East Asian women 51/4470 (1.1%)). Relative to Australian/New Zealand-born English speakers, immigrants had a lower risk of pre-eclampsia overall (adjusted OR 0.67; 95% CI 0.60-0.75); as did the three largest immigrant groups examined: Southern Asian (0.73; 0.62-0.85), Middle-Eastern/African (0.55; 0.47-0.66) and North-East Asian (0.33; 0.25-0.45) women. Findings were similar for nulliparous women. CONCLUSIONS: Certain immigrant groups are at lower risk of pre-eclampsia than Australian/New Zealand-born English-speaking women. Understanding why this is so may lead to better screening and preventive strategies in higher-risk women.

6.
JAMA Netw Open ; 2(10): e1912614, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31577362

RESUMO

Importance: Supine maternal position in the third trimester is associated with reduced uterine blood flow and increased risk of late stillbirth. As reduced uterine blood flow is also associated with fetal growth restriction, this study explored the association between the position in which pregnant women went to sleep and infant birth weight. Objective: To examine the association between supine position when going to sleep in women after 28 weeks of pregnancy and lower birth weight and birth weight centiles. Design, Setting, and Participants: Prespecified subgroup analysis using data from controls in an individual participant data meta-analysis of 4 case-control studies investigating sleep and stillbirth in New Zealand, Australia, and the United Kingdom. Participants were women with ongoing pregnancies at 28 weeks' gestation or more at interview. Main Outcomes and Measures: The primary outcome was adjusted mean difference (aMD) in birth weight. Secondary outcomes were birth weight centiles (INTERGROWTH-21st and customized) and adjusted odds ratios (aORs) for birth weight less than 50th and less than 10th centile (small for gestational age) for supine vs nonsupine going-to-sleep position in the last 1 to 4 weeks, adjusted for variables known to be associated with birth size. Results: Of 1760 women (mean [SD] age, 30.25 [5.46] years), 57 (3.2%) reported they usually went to sleep supine during the previous 1 to 4 weeks. Adjusted mean (SE) birth weight was 3410 (112) g among women who reported supine position and 3554 (98) g among women who reported nonsupine position (aMD, 144 g; 95% CI, -253 to -36 g; P = .009), representing an approximate 10-percentile reduction in adjusted mean INTERGROWTH-21st (48.5 vs 58.6; aMD, -10.1; 95% CI, -17.1 to -3.1) and customized (40.7 vs 49.7; aMD, -9.0; 95% CI, -16.6 to -1.4) centiles. There was a nonsignificant increase in birth weight at less than the 50th INTERGROWTH-21st centile (aOR, 1.90; 95% CI, 0.83-4.34) and a 2-fold increase in birth weight at less than the 50th customized centile (aOR, 2.12; 95% CI, 1.20-3.76). Going to sleep supine was associated with a 3-fold increase in small for gestational age birth weight by INTERGROWTH-21st standards (aOR, 3.23; 95% CI, 1.37-7.59) and a nonsignificant increase in small for gestational age birth weight customized standards (aOR, 1.63; 95% CI, 0.77-3.44). Conclusions and Relevance: This study found that going to sleep in a supine position in late pregnancy was independently associated with reduced birth weight and birth weight centile. This novel association is biologically plausible and likely modifiable. Public health campaigns that encourage women in the third trimester of pregnancy to settle to sleep on their side have potential to optimize birth weight.

8.
PLoS One ; 14(9): e0222117, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31553736

RESUMO

BACKGROUND: Commercial or industry funding is associated with outcomes that favour the study funder in published studies, across various areas of research. However, it is currently unclear whether there are differences between trials with and without industry involvement at the stage of trial registration. OBJECTIVE: To determine whether industry involvement (industry sponsorship, funding, or collaboration) is associated with trial characteristics at the time of trial registration. METHODS: We conducted a cross-sectional analysis of all interventional studies registered on the Australian New Zealand Clinical Trials Registry in 2017 and classified them by industry involvement. We analysed whether there were differences in study characteristics (including type of control, sample size, study phase, randomisation, registration timing, and purpose of study) by industry involvement. RESULTS: Industry involvement was reported by 21% of the 1,433 included trials. Only 40% of trials with industry involvement used an active control compared to 58% of non-industry trials (OR = 0.49, 95%CI = 0.38 to 0.63, p < .001), and industry trials reported smaller sample sizes (Median(IQR)industry = 45(24-100), Median(IQR)non-industry = 70(35-160), Mean Difference = -153, 95% CI = -233 to -75, p < .001). Industry trials were more likely to be earlier phase trials (Χ2(df) = 71.46(4), p < .001). There was no difference in use of randomisation between industry (70%) and non-industry trials (73%) (OR = 0.88, 95%CI = 0.67-1.20, p = .38). Eighty-three percent of industry trials compared to 70% of non-industry trials were prospectively registered (OR = 2.02, 95%CI = 1.47-2.82, p < .001). Industry trials were more likely to assess treatment (85%), rather than prevention, education or diagnosis compared to non-industry trials (64%) (OR = 3.02, 95%CI = 2.17-4.32, p < .001). CONCLUSION: The current study gives insight into differences in trial characteristics by industry involvement at registration stage. There was a reduced use of active controls in trials with industry involvement which has previously been proposed as a mechanism behind more favourable results. Non-industry funders and sponsors are crucial to ensure research addresses not only treatments, but also prevention, diagnosis and education questions.

9.
Clin Perinatol ; 46(3): 579-591, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31345548

RESUMO

Participant data from approximately 5000 infants have been meta-analyzed to guide oxygen saturation policy for extremely preterm infants. The Neonatal Oxygenation Prospective Meta-analysis showed that targeting a higher oxygen saturation range compared with a lower range resulted in decreased death and necrotizing enterocolitis and no difference in major disability but increased treated retinopathy of prematurity (ROP) and supplemental oxygen use at 36 weeks' postmenstrual age. The 91% to 95% range can be recommended for all extremely preterm infants from birth but should be accompanied by stringent surveillance for the prevention and early treatment of ROP.

10.
Cochrane Database Syst Rev ; 7: CD004204, 2019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-31314903

RESUMO

BACKGROUND: Preterm infants may accumulate nutrient deficits leading to extrauterine growth restriction. Feeding preterm infants with nutrient-enriched rather than standard formula might increase nutrient accretion and growth rates and might improve neurodevelopmental outcomes. OBJECTIVES: To compare the effects of feeding with nutrient-enriched formula versus standard formula on growth and development of preterm infants. SEARCH METHODS: We used the Cochrane Neonatal standard search strategy. This included electronic searches of the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 11), MEDLINE, Embase, and the Cumulative Index to Nursing and Allied Health Literature (until November 2018), as well as conference proceedings, previous reviews, and clinical trials databases. SELECTION CRITERIA: Randomised and quasi-randomised controlled trials that compared feeding preterm infants with nutrient-enriched formula (protein and energy plus minerals, vitamins, or other nutrients) versus standard formula. DATA COLLECTION AND ANALYSIS: We extracted data using the Cochrane Neonatal standard methods. Two review authors separately evaluated trial quality and extracted and synthesised data using risk ratios (RRs), risk differences, and mean differences (MDs). We assessed certainty of evidence at the outcome level using Grading of Recommendations Assessment, Development and Evaluation (GRADE) methods. MAIN RESULTS: We identified seven trials in which a total of 590 preterm infants participated. Most participants were clinically stable preterm infants of birth weight less than 1850 g. Few participants were extremely preterm, extremely low birth weight, or growth restricted at birth. Trials were conducted more than 30 years ago, were formula industry funded, and were small with methodological weaknesses (including lack of masking) that might bias effect estimates. Meta-analyses of in-hospital growth parameters were limited by statistical heterogeneity. There is no evidence of an effect on time to regain birth weight (MD -1.48 days, 95% confidence interval (CI) -4.73 to 1.77) and low-certainty evidence suggests that feeding with nutrient-enriched formula increases in-hospital rates of weight gain (MD 2.43 g/kg/d, 95% CI 1.60 to 3.26) and head circumference growth (MD 1.04 mm/week, 95% CI 0.18 to 1.89). Meta-analysis did not show an effect on the average rate of length gain (MD 0.22 mm/week, 95% CI -0.70 to 1.13). Fewer data are available for growth and developmental outcomes assessed beyond infancy, and these do not show consistent effects of nutrient-enriched formula feeding. Data from two trials did not show an effect on Bayley Mental Development Index scores at 18 months post term (MD 2.87, 95% CI -1.38 to 7.12; moderate-certainty evidence). Infants who received nutrient-enriched formula had higher Bayley Psychomotor Development Index scores at 18 months post term (MD 6.56. 95% CI 2.87 to 10.26; low-certainty evidence), but no evidence suggested an effect on cerebral palsy (typical RR 0.79, 95% CI 0.30 to 2.07; 2 studies, 377 infants). Available data did not indicate any other benefits or harms and provided low-certainty evidence about the effect of nutrient-enriched formula feeding on the risk of necrotising enterocolitis in preterm infants (typical RR 0.72, 95% CI 0.41 to 1.25; 3 studies, 489 infants). AUTHORS' CONCLUSIONS: Available trial data show that feeding preterm infants nutrient-enriched (compared with standard) formulas has only modest effects on growth rates during their initial hospital admission. No evidence suggests effects on long-term growth or development. The GRADE assessment indicates that the certainty of this evidence is low, and that these findings should be interpreted and applied with caution. Further randomised trials would be needed to resolve this uncertainty.


Assuntos
Alimentos Formulados , Fórmulas Infantis , Fenômenos Fisiológicos da Nutrição do Lactente/fisiologia , Recém-Nascido de Baixo Peso/crescimento & desenvolvimento , Recém-Nascido Prematuro/crescimento & desenvolvimento , Ingestão de Energia/fisiologia , Humanos , Fórmulas Infantis/normas , Recém-Nascido , Ensaios Clínicos Controlados Aleatórios como Assunto , Ganho de Peso
11.
EClinicalMedicine ; 10: 49-57, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31193832

RESUMO

Background: Maternal supine going-to-sleep position has been associated with increased risk of late stillbirth (≥ 28 weeks), but it is unknown if the risk differs between right and left side, and if some pregnancies are more vulnerable. Methods: Systematic searches were undertaken for an individual-level participant data (IPD) meta-analysis of case-control studies, prospective cohort studies and randomised trials undertaken up until 26 Jan, 2018, that reported data on maternal going-to-sleep position and stillbirth. Participant inclusion criteria included gestation ≥ 28 weeks', non-anomalous, singleton pregnancies. The primary outcome was stillbirth. A one-stage approach stratified by study and site was used for the meta-analysis. The interaction between supine going-to-sleep position and fetal vulnerability was assessed by bi-variable regression. The multivariable model was adjusted for a priori confounders. Registration number: PROSPERO, CRD42017047703. Findings: Six case-control studies were identified, with data obtained from five (cases, n = 851; controls, n = 2257). No data was provided by a sixth study (cases, n = 100; controls, n = 200). Supine going-to-sleep position was associated with increased odds of late stillbirth (adjusted odds ratio [aOR] 2.63, 95% CI 1.72-4.04, p < 0.0001) compared with left side. Right side had similar odds to left (aOR 1.04, 95% CI 0.83-1.31, p = 0.75). There were no significant interactions between supine going-to-sleep position and assessed indicators of fetal vulnerability, including small-for-gestational-age infants (p = 0.32), maternal obesity (p = 0.08), and smoking (p = 0.86). The population attributable risk for supine going-to-sleep position was 5.8% (3.2-9.2). Interpretation: This IPD meta-analysis confirms that supine going-to-sleep position is independently associated with late stillbirth. Going-to-sleep on left or right side appears equally safe. No significant interactions with our assessed indicators of fetal vulnerability were identified, therefore, supine going-to-sleep position can be considered a contributing factor for late stillbirth in all pregnancies. This finding could reduce late stillbirth by 5.8% if every pregnant woman ≥ 28 weeks' gestation settled to sleep on her side.

12.
J Clin Epidemiol ; 113: 64-74, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31121304

RESUMO

OBJECTIVES: The objective of this study was to determine the prevalence of trial registration in health research, whether trial registration status and timing vary depending on trial characteristics, and the relationship between trial registration status and risk of bias. STUDY DESIGN AND SETTING: We systematically reviewed all clinical trials published from January to June 2017 in 28 high- and low-impact factor general and specialty medicine journals. RESULTS: We identified 370 trials and assessed risk of bias in 183 trials. Trial registration rates were high; 95% of trials were registered prospectively or retrospectively before enrollment completion. Larger sample size, multiple recruitment countries, and primary industry funding were all predictors of earlier trial registration. Prospectively registered trials had a significantly lower risk of bias compared to unregistered trials across all domains. Prospectively registered trials had a similar risk of bias compared to retrospectively registered trials across four out of six domains, and a lower risk of bias across the remaining two domains. CONCLUSION: Trial registration is an imperfect proxy for risk of bias. Systematic reviewers should assess risk of bias on a case-by-case basis and conduct sensitivity analyses excluding high risk of bias studies. In the longer term, mechanisms should be implemented to facilitate prospective registration of all trials.

14.
PLoS Med ; 16(4): e1002771, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30978205

RESUMO

BACKGROUND: Infants born preterm compared with infants born at term are at an increased risk of dying and of serious morbidities in early life, and those who survive have higher rates of neurological impairments. It remains unclear whether exposure to repeat courses of prenatal corticosteroids can reduce these risks. This individual participant data (IPD) meta-analysis (MA) assessed whether repeat prenatal corticosteroid treatment given to women at ongoing risk of preterm birth in order to benefit their infants is modified by participant or treatment factors. METHODS AND FINDINGS: Trials were eligible for inclusion if they randomised women considered at risk of preterm birth who had already received an initial, single course of prenatal corticosteroid seven or more days previously and in which corticosteroids were compared with either placebo or no placebo. The primary outcomes for the infants were serious outcome, use of respiratory support, and birth weight z-scores; for the children, they were death or any neurosensory disability; and for the women, maternal sepsis. Studies were identified using the Cochrane Pregnancy and Childbirth search strategy. Date of last search was 20 January 2015. IPD were sought from investigators with eligible trials. Risk of bias was assessed using criteria from the Cochrane Collaboration. IPD were analysed using a one-stage approach. Eleven trials, conducted between 2002 and 2010, were identified as eligible, with five trials being from the United States, two from Canada, and one each from Australia and New Zealand, Finland, India, and the United Kingdom. All 11 trials were included, with 4,857 women and 5,915 infants contributing data. The mean gestational age at trial entry for the trials was between 27.4 weeks and 30.2 weeks. There was no significant difference in the proportion of infants with a serious outcome (relative risk [RR] 0.92, 95% confidence interval [CI] 0.82 to 1.04, 5,893 infants, 11 trials, p = 0.33 for heterogeneity). There was a reduction in the use of respiratory support in infants exposed to repeat prenatal corticosteroids compared with infants not exposed (RR 0.91, 95% CI 0.85 to 0.97, 5,791 infants, 10 trials, p = 0.64 for heterogeneity). The number needed to treat (NNT) to benefit was 21 (95% CI 14 to 41) women/fetus to prevent one infant from needing respiratory support. Birth weight z-scores were lower in the repeat corticosteroid group (mean difference -0.12, 95%CI -0.18 to -0.06, 5,902 infants, 11 trials, p = 0.80 for heterogeneity). No statistically significant differences were seen for any of the primary outcomes for the child (death or any neurosensory disability) or for the woman (maternal sepsis). The treatment effect varied little by reason the woman was considered to be at risk of preterm birth, the number of fetuses in utero, the gestational age when first trial treatment course was given, or the time prior to birth that the last dose was given. Infants exposed to between 2-5 courses of repeat corticosteroids showed a reduction in both serious outcome and the use of respiratory support compared with infants exposed to only a single repeat course. However, increasing numbers of repeat courses of corticosteroids were associated with larger reductions in birth z-scores for weight, length, and head circumference. Not all trials could provide data for all of the prespecified subgroups, so this limited the power to detect differences because event rates are low for some important maternal, infant, and childhood outcomes. CONCLUSIONS: In this study, we found that repeat prenatal corticosteroids given to women at ongoing risk of preterm birth after an initial course reduced the likelihood of their infant needing respiratory support after birth and led to neonatal benefits. Body size measures at birth were lower in infants exposed to repeat prenatal corticosteroids. Our findings suggest that to provide clinical benefit with the least effect on growth, the number of repeat treatment courses should be limited to a maximum of three and the total dose to between 24 mg and 48 mg.


Assuntos
Corticosteroides/administração & dosagem , Corticosteroides/efeitos adversos , Resultado da Gravidez/epidemiologia , Nascimento Prematuro/prevenção & controle , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Adulto , Ensaios Clínicos como Assunto/estatística & dados numéricos , Esquema de Medicação , Feminino , Humanos , Recém-Nascido , Trabalho de Parto Prematuro/epidemiologia , Trabalho de Parto Prematuro/prevenção & controle , Parto/efeitos dos fármacos , Gravidez , Nascimento Prematuro/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Recidiva , Medição de Risco , Fatores de Risco , Adulto Jovem
15.
BMJ Open ; 9(4): e025580, 2019 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-30948584

RESUMO

OBJECTIVES: To identify and review evaluations of strategies to recruit men aged 50 years and over to randomised controlled trials (RCTs). DESIGN: Systematic review and narrative synthesis. DATA SOURCES: MEDLINE, EMBASE, CINAHL and ORRCA databases were searched to 1 December 2017. ELIGIBILITY CRITERIA: Studies using quantitative methods to evaluate recruitment strategies to RCTs of men aged 50 years and older. DATA EXTRACTION AND SYNTHESIS: A single reviewer extracted data (for each strategy, number of participants approached, screened and randomised, and cost). Study quality was assessed using National Heart, Lung and Blood Institute Quality Assessment Tools and considered study design, description of interventions, description and measurement of outcomes, completeness of outcome reporting, performance of statistical testing and consideration of confounders. Recruitment strategies were categorised by the recruitment stage they addressed. RESULTS: Sixteen studies (n >14 000) were included: one good quality, ten fair quality and five poor quality. Studies evaluated strategies to identify prospective participants, and to improve the processes for assessing participant eligibility, providing participant information and seeking consent. In good and fair quality studies, the most effective strategies for identifying participants were referral from an affiliated health service provider (two studies), mass mailing (five studies) and media coverage (two studies). Community outreach activities such as displaying posters and attending local community events were not effective (two studies). Trial-specific training of site recruitment staff, developed using qualitative analysis of recruitment visits (two studies), and provision of study information to prospective participants at a multidisciplinary, group information session (one study) both improved recruitment. CONCLUSION: Improved engagement of men aged 50 years and older in RCTs is needed. A gender-sensitised approach to RCT recruitment may help to address this need. We have identified several promising recruitment strategies that merit further evaluation. PROSPERO REGISTRATION NUMBER: CRD42017060301.

16.
Trials ; 20(1): 161, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30841935

RESUMO

BACKGROUND: Inadequate and poor quality outcome reporting in clinical trials is a well-documented problem that impedes the ability of researchers to evaluate, replicate, synthesize, and build upon study findings and impacts evidence-based decision-making by patients, clinicians, and policy-makers. To facilitate harmonized and transparent reporting of outcomes in trial protocols and published reports, the Instrument for reporting Planned Endpoints in Clinical Trials (InsPECT) is being developed. The final product will provide unique InsPECT extensions to the SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) and CONSORT (Consolidated Standards of Reporting Trials) reporting guidelines. METHODS: The InsPECT SPIRIT and CONSORT extensions will be developed in accordance with the methodological framework created by the EQUATOR (Enhancing the Quality and Transparency of Health Research Quality) Network for reporting guideline development. Development will consist of (1) the creation of an initial list of candidate outcome reporting items synthesized from expert consultations and a scoping review of existing guidance for reporting outcomes in trial protocols and reports; (2) a three-round international Delphi study to identify additional candidate items and assess candidate item importance on a 9-point Likert scale, completed by stakeholders such as trial report and protocol authors, systematic review authors, biostatisticians and epidemiologists, reporting guideline developers, clinicians, journal editors, and research ethics board representatives; and (3) an in-person expert consensus meeting to finalize the set of essential outcome reporting items for trial protocols and reports, respectively. The consensus meeting discussions will be independently facilitated and informed by the empirical evidence identified in the primary literature and through the opinions (aggregate rankings and comments) collected via the Delphi study. An integrated knowledge translation approach will be used throughout InsPECT development to facilitate implementation and dissemination, in addition to standard post-development activities. DISCUSSION: InsPECT will provide evidence-informed and consensus-based standards focused on outcome reporting in clinical trials that can be applied across diverse disease areas, study populations, and outcomes. InsPECT will support the standardization of trial outcome reporting, which will maximize trial usability, reduce bias, foster trial replication, improve trial design and execution, and ultimately reduce research waste and help improve patient outcomes.


Assuntos
Ensaios Clínicos como Assunto/normas , Determinação de Ponto Final/normas , Projetos de Pesquisa/normas , Ensaios Clínicos como Assunto/métodos , Consenso , Conferências de Consenso como Assunto , Técnica Delfos , Humanos , Literatura de Revisão como Assunto , Resultado do Tratamento
17.
Eur J Obstet Gynecol Reprod Biol ; 229: 159-166, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30199814

RESUMO

OBJECTIVE: To assess the accuracy of the National Institute of Health and Care Excellence (NICE) and United States Preventive Services Task Force (USPSTF) guidelines for predicting pre-eclampsia in pregnancy to guide aspirin prophylaxis. STUDY DESIGN: We conducted an individual participant data meta-analysis using the Perinatal Antiplatelet Review of International Studies (PARIS) dataset. This dataset includes randomised controlled trials (RCTs) of antiplatelet therapy for primary prevention of pre-eclampsia conducted in international antenatal care settings. RCTs were eligible if they enrolled pregnant women up to 28 weeks'gestation, reported risk factors, and assessed pre-eclampsia. Women assigned to the control arm (no antiplatelet agent) were included. Both guidelines recommend aspirin if ≥1 high-risk factors or ≥2 moderate-risk factors. Two moderate-risk factors (body mass index and pregnancy interval) were unavailable. Pre-eclampsia was the primary outcome. The secondary outcomes were pre-eclampsia defined by gestational age at delivery (<37 weeks versus ≥37 weeks; <34 weeks versus ≥34 weeks). We assessed the performance of the NICE and USPSTF approaches for parous and nulliparous women by estimating sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for predicting pre-eclampsia, the number-needed-to-screen (NNS) and the number-needed-to-treat (NNT) to prevent one pre-eclampsia event. RESULTS: Three RCTs were eligible (4524 women, 221 pre-eclampsia cases). Using the NICE guidelines, 9.4% of 1020 parous women were classified as screen-positive with a sensitivity of 26.4% (95% confidence interval 16.4-39.6%), specificity 91.5% (89.6-93.1%), PPV 14.6% (8.9-23.0%) and NPV 95.8% (94.3-96.9%). The NNS was 729 and NNT 69. For 3504 nulliparous women, 3% were classified as screen-positive with a sensitivity of 8.9% (5.5-14.4%), specificity 97.2% (96.6-97.8%), PPV 14.2% (8.7-21.9%), NPV 95.5% (94.8-96.1%). The NNS was 2336 and NNT 71. The USPSTF approach demonstrated similar performance. CONCLUSION: The NICE and USPSTF guidelines offer a simple and specific approach for recommending aspirin prophylaxis for women at high-risk of pre-eclampsia where more advanced screening methods are not available. However, the low detection rate limits its value in clinical practice, in particular for nulliparous women, and raises the need for development of an improved simple risk prediction tool.


Assuntos
Guias de Prática Clínica como Assunto , Pré-Eclâmpsia/prevenção & controle , Aspirina/uso terapêutico , Feminino , Humanos , Paridade , Inibidores da Agregação de Plaquetas/uso terapêutico , Gravidez , Medição de Risco
19.
JAMA ; 319(21): 2190-2201, 2018 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-29872859

RESUMO

Importance: There are potential benefits and harms of hyperoxemia and hypoxemia for extremely preterm infants receiving more vs less supplemental oxygen. Objective: To compare the effects of different target ranges for oxygen saturation as measured by pulse oximetry (Spo2) on death or major morbidity. Design, Setting, and Participants: Prospectively planned meta-analysis of individual participant data from 5 randomized clinical trials (conducted from 2005-2014) enrolling infants born before 28 weeks' gestation. Exposures: Spo2 target range that was lower (85%-89%) vs higher (91%-95%). Main Outcomes and Measures: The primary outcome was a composite of death or major disability (bilateral blindness, deafness, cerebral palsy diagnosed as ≥2 level on the Gross Motor Function Classification System, or Bayley-III cognitive or language score <85) at a corrected age of 18 to 24 months. There were 16 secondary outcomes including the components of the primary outcome and other major morbidities. Results: A total of 4965 infants were randomized (2480 to the lower Spo2 target range and 2485 to the higher Spo2 range) and had a median gestational age of 26 weeks (interquartile range, 25-27 weeks) and a mean birth weight of 832 g (SD, 190 g). The primary outcome occurred in 1191 of 2228 infants (53.5%) in the lower Spo2 target group and 1150 of 2229 infants (51.6%) in the higher Spo2 target group (risk difference, 1.7% [95% CI, -1.3% to 4.6%]; relative risk [RR], 1.04 [95% CI, 0.98 to 1.09], P = .21). Of the 16 secondary outcomes, 11 were null, 2 significantly favored the lower Spo2 target group, and 3 significantly favored the higher Spo2 target group. Death occurred in 484 of 2433 infants (19.9%) in the lower Spo2 target group and 418 of 2440 infants (17.1%) in the higher Spo2 target group (risk difference, 2.8% [95% CI, 0.6% to 5.0%]; RR, 1.17 [95% CI, 1.04 to 1.31], P = .01). Treatment for retinopathy of prematurity was administered to 220 of 2020 infants (10.9%) in the lower Spo2 target group and 308 of 2065 infants (14.9%) in the higher Spo2 target group (risk difference, -4.0% [95% CI, -6.1% to -2.0%]; RR, 0.74 [95% CI, 0.63 to 0.86], P < .001). Severe necrotizing enterocolitis occurred in 227 of 2464 infants (9.2%) in the lower Spo2 target group and 170 of 2465 infants (6.9%) in the higher Spo2 target group (risk difference, 2.3% [95% CI, 0.8% to 3.8%]; RR, 1.33 [95% CI, 1.10 to 1.61], P = .003). Conclusions and Relevance: In this prospectively planned meta-analysis of individual participant data from extremely preterm infants, there was no significant difference between a lower Spo2 target range compared with a higher Spo2 target range on the primary composite outcome of death or major disability at a corrected age of 18 to 24 months. The lower Spo2 target range was associated with a higher risk of death and necrotizing enterocolitis, but a lower risk of retinopathy of prematurity treatment.


Assuntos
Deficiências do Desenvolvimento/epidemiologia , Enterocolite Necrosante/epidemiologia , Lactente Extremamente Prematuro , Doenças do Prematuro/epidemiologia , Oxigênio/sangue , Cegueira/epidemiologia , Paralisia Cerebral/epidemiologia , Surdez/epidemiologia , Feminino , Humanos , Incidência , Lactente , Mortalidade Infantil , Recém-Nascido , Doenças do Prematuro/mortalidade , Estimativa de Kaplan-Meier , Masculino , Oximetria , Oxigênio/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto
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