Objectives To assess the association between maternal glucose concentrations and adverse perinatal outcomes in women without gestational or existing diabetes and to determine whether clear thresholds for identifying women at risk of perinatal outcomes can be identified.Design Systematic review and meta-analysis of prospective cohort studies and control arms of randomised trials.Data sources Databases including Medline and Embase were searched up to October 2014 and combined with individual participant data from two additional birth cohorts.Eligibility criteria for selecting studies Studies including pregnant women with oral glucose tolerance (OGTT) or challenge (OGCT) test results, with data on at least one adverse perinatal outcome.Appraisal and data extraction Glucose test results were extracted for OGCT (50 g) and OGTT (75 g and 100 g) at fasting and one and two hour post-load timings. Data were extracted on induction of labour; caesarean and instrumental delivery; pregnancy induced hypertension; pre-eclampsia; macrosomia; large for gestational age; preterm birth; birth injury; and neonatal hypoglycaemia. Risk of bias was assessed with a modified version of the critical appraisal skills programme and quality in prognostic studies tools.Results 25 reports from 23 published studies and two individual participant data cohorts were included, with up to 207 172 women (numbers varied by the test and outcome analysed in the meta-analyses). Overall most studies were judged as having a low risk of bias. There were positive linear associations with caesarean section, induction of labour, large for gestational age, macrosomia, and shoulder dystocia for all glucose exposures across the distribution of glucose concentrations. There was no clear evidence of a threshold effect. In general, associations were stronger for fasting concentration than for post-load concentration. For example, the odds ratios for large for gestational age per 1 mmol/L increase of fasting and two hour post-load glucose concentrations (after a 75 g OGTT) were 2.15 (95% confidence interval 1.60 to 2.91) and 1.20 (1.13 to 1.28), respectively. Heterogeneity was low between studies in all analyses.Conclusions This review and meta-analysis identified a large number of studies in various countries. There was a graded linear association between fasting and post-load glucose concentration across the whole glucose distribution and most adverse perinatal outcomes in women without pre-existing or gestational diabetes. The lack of a clear threshold at which risk increases means that decisions regarding thresholds for diagnosing gestational diabetes are somewhat arbitrary. Research should now investigate the clinical and cost-effectiveness of applying different glucose thresholds for diagnosis of gestational diabetes on perinatal and longer term outcomes.Systematic review registration PROSPERO CRD42013004608

During the last decade, there has been a rapid increase in development of instruments to measure parent food practices. Because these instruments often measure different constructs, or define common constructs differently, an evaluation of these instruments is needed. A systematic review of the literature was conducted to identify existing measures of parent food practices and to assess the quality of their development. The initial search used terms capturing home environment, parenting behaviors, feeding practices and eating behaviors, and was performed in October of 2009 using PubMed/Medline, PsychInfo, Web of knowledge (ISI), and ERIC, and updated in July of 2012. A review of titles and abstracts was used to narrow results, after which full articles were retrieved and reviewed. Only articles describing development of measures of parenting food practices designed for families with children 2-12 years old were retained for the current review. For each article, two reviewers extracted data and appraised the quality of processes used for instrument development and evaluation. The initial search yielded 28,378 unique titles; review of titles and abstracts narrowed the pool to 1,352 articles; from which 57 unique instruments were identified. The review update yielded 1,772 new titles from which14 additional instruments were identified. The extraction and appraisal process found that 49% of instruments clearly identified and defined concepts to be measured, and 46% used theory to guide instrument development. Most instruments (80%) had some reliability testing, with internal consistency being the most common (79%). Test-retest or inter-rater reliability was reported for less than half the instruments. Some form of validity evidence was reported for 84% of instruments. Construct validity was most commonly presented (86%), usually with analysis of associations with child diet or weight/BMI. While many measures of food parenting practices have emerged, particularly in recent years, few have demonstrated solid development methods. Substantial variation in items across different scales/constructs makes comparison between instruments extremely difficult. Future efforts should be directed toward consensus development of food parenting practices constructs and measures.

SummaryThe relationship between television (TV) viewing and overweight in children is likely to be influenced by the quality of measures used. We systematically reviewed studies related to overweight in children that had included a measure of TV exposure. Literature searches were conducted in MedLINE, PsychInfo, SportDiscus and ISIWeb of Science. Methods of assessing TV viewing were evaluated, including the type of measure, the administration procedure and reported psychometric properties. The majority of studies assessed TV viewing using self-report surveys and very few studies used direct observation. The validity or reliability of measures was often not examined. The majority of tools that were evaluated were compared with another self-report measure or an objective measure of physical activity. TV viewing measures should be selected that are specific to the research question, the study design, as well as methodological feasibility. However, it is recommended that measures of TV viewing be used only if they have psychometric data to support their validity and reliability. Selecting measures that are valid and reliable enables us to examine with greater accuracy the influence of TV viewing on childhood overweight, as well as the efficacy of interventions designed to reduce TV viewing in children.

Background: The contribution of the environment to the obesity epidemic is well recognized. Parents have control over their home environment and can, therefore, support healthy dietary and activity habits in their children by manipulating factors such as access to energy-dense foods, availability of physical activity equipment, and restricting screen time. This paper describes the development of the Healthy Home Survey and its reliability and validity. The Healthy Home Survey was designed to assess characteristics of the home environment that are hypothesized to influence healthy weight behaviors in children including diet and physical activity.

BackgroundEarly interventions are recognised as key to improving life chances for children and reducing inequalities in health and well-being, however there is a paucity of high quality research into the effectiveness of interventions to address childhood health and development outcomes. Planning and implementing standalone RCTs for multiple, individual interventions would be slow, cumbersome and expensive. This paper describes the protocol for an innovative experimental birth cohort: Born in Bradford’s Better Start (BiBBS) that will simultaneously evaluate the impact of multiple early life interventions using efficient study designs. Better Start Bradford (BSB) has been allocated £49 million from the Big Lottery Fund to implement 22 interventions to improve outcomes for children aged 0–3 in three key areas: social and emotional development; communication and language development; and nutrition and obesity. The interventions will be implemented in three deprived and ethnically diverse inner city areas of Bradford.MethodThe BiBBS study aims to recruit 5000 babies, their mothers and their mothers’ partners over 5 years from January 2016-December 2020. Demographic and socioeconomic information, physical and mental health, lifestyle factors and biological samples will be collected during pregnancy. Parents and children will be linked to their routine health and local authority (including education) data throughout the children’s lives. Their participation in BSB interventions will also be tracked. BiBBS will test interventions using the Trials within Cohorts (TwiCs) approach and other quasi-experimental designs where TwiCs are neither feasible nor ethical, to evaluate these early life interventions. The effects of single interventions, and the cumulative effects of stacked (multiple) interventions on health and social outcomes during the critical early years will be measured.DiscussionThe focus of the BiBBS cohort is on intervention impact rather than observation. As far as we are aware BiBBS is the world’s first such experimental birth cohort study. While some risk factors for adverse health and social outcomes are increasingly well described, the solutions to tackling them remain elusive. The novel design of BiBBS can contribute much needed evidence to inform policy makers and practitioners about effective approaches to improve health and well-being for future generations.Electronic supplementary materialThe online version of this article (doi:10.1186/s12889-016-3318-0) contains supplementary material, which is available to authorized users.

ObjectiveTo investigate the effectiveness of different treatments for gestational diabetes mellitus (GDM).DesignSystematic review, meta-analysis and network meta-analysis.MethodsData sources were searched up to July 2016 and included MEDLINE and Embase. Randomised trials comparing treatments for GDM (packages of care (dietary and lifestyle interventions with pharmacological treatments as required), insulin, metformin, glibenclamide (glyburide)) were selected by two authors and double checked for accuracy. Outcomes included large for gestational age, shoulder dystocia, neonatal hypoglycaemia, caesarean section and pre-eclampsia. We pooled data using random-effects meta-analyses and used Bayesian network meta-analysis to compare pharmacological treatments (ie, including treatments not directly compared within a trial).ResultsForty-two trials were included, the reporting of which was generally poor with unclear or high risk of bias. Packages of care varied in their composition and reduced the risk of most adverse perinatal outcomes compared with routine care (eg, large for gestational age: relative risk0.58 (95% CI 0.49 to 0.68; I2=0%; trials 8; participants 3462). Network meta-analyses suggest that metformin had the highest probability of being the most effective treatment in reducing the risk of most outcomes compared with insulin or glibenclamide.ConclusionsEvidence shows that packages of care are effective in reducing the risk of most adverse perinatal outcomes. However, trials often include few women, are poorly reported with unclear or high risk of bias and report few outcomes. The contribution of each treatment within the packages of care remains unclear. Large well-designed and well-conducted trials are urgently needed.Trial registration numberPROSPERO CRD42013004608.

SummaryEvidence for the health impact of obesity has largely focussed on adults. We estimated the population prevalence and prevalence ratio of obesity‐associated comorbidities in children and adolescents aged 5 to 18 years. Five databases were searched from inception to 14 January 2018. Population‐based observational studies reporting comorbidity prevalence by weight category (healthy weight/overweight/obese) in children and adolescents aged 5 to 18 years from any country were eligible. Comorbidity prevalence, stratified by weight category, was extracted and prevalence ratios (relative to healthy weight) estimated using random effects meta‐analyses. Of 9183 abstracts, 52 eligible studies (1 553 683 participants) reported prevalence of eight comorbidities or risk markers including diabetes and nonalcoholic fatty liver disease (NAFLD). Evidence for psychological comorbidities was lacking. Meta‐analyses suggested prevalence ratio for prediabetes (fasting glucose ≥ 100 mg/dL) for those with obesity relative to those of a healthy weight was 1.4 (95% confidence interval [CI], 1.2‐1.6) and for NAFLD 26.1 (9.4‐72.3). In the general population, children and adolescents with overweight/obesity have a higher prevalence of comorbidities relative to those of a healthy weight. This review provides clinicians with information when assessing children and researchers a foundation upon which to build a comprehensive dataset to understand the health consequences of childhood obesity.

BackgroundEasily identifiable risk factors including: obesity and ethnicity at high risk of diabetes are commonly used to indicate which women should be offered the oral glucose tolerance test (OGTT) to diagnose gestational diabetes (GDM). Evidence regarding these risk factors is limited however. We conducted a systematic review (SR) and meta-analysis and individual participant data (IPD) analysis to evaluate the performance of risk factors in identifying women with GDM.MethodsWe searched MEDLINE, Medline in Process, Embase, Maternity and Infant Care and the Cochrane Central Register of Controlled Trials (CENTRAL) up to August 2016 and conducted additional reference checking. We included observational, cohort, case-control and cross-sectional studies reporting the performance characteristics of risk factors used to identify women at high risk of GDM. We had access to IPD from the Born in Bradford and Atlantic Diabetes in Pregnancy cohorts, all pregnant women in the two cohorts with data on risk factors and OGTT results were included.ResultsTwenty nine published studies with 211,698 women for the SR and a further 14,103 women from two birth cohorts (Born in Bradford and the Atlantic Diabetes in Pregnancy study) for the IPD analysis were included. Six studies assessed the screening performance of guidelines; six examined combinations of risk factors; eight evaluated the number of risk factors and nine examined prediction models or scores. Meta-analysis using data from published studies suggests that irrespective of the method used, risk factors do not identify women with GDM well.Using IPD and combining risk factors to produce the highest sensitivities, results in low specificities (and so higher false positives). Strategies that use the risk factors of age (>25 or >30) and BMI (>25 or 30) perform as well as other strategies with additional risk factors included.ConclusionsRisk factor screening methods are poor predictors of which pregnant women will be diagnosed with GDM. A simple approach of offering an OGTT to women 25 years or older and/or with a BMI of 25kg/m2 or more is as good as more complex risk prediction models. Research to identify more accurate (bio)markers is needed.Systematic Review Registration: PROSPERO CRD42013004608