scispace - formally typeset
Search or ask a question
Institution

World Health Organization

GovernmentIslamabad, Pakistan
About: World Health Organization is a government organization based out in Islamabad, Pakistan. It is known for research contribution in the topics: Population & Public health. The organization has 13330 authors who have published 22232 publications receiving 1322023 citations. The organization is also known as: World Health Organisation & WHO.


Papers
More filters
Journal ArticleDOI
TL;DR: An overview of the defining features, design variations, strengths, and weaknesses of vignette studies as a way of examining how health professionals form clinical judgments and how they are being used to investigate clinicians’ diagnostic decisions in case-controlled field studies for the ICD-11 classification of mental and behavioural disorders.

402 citations

Journal ArticleDOI
TL;DR: Women receiving iron were on average more likely to have higher haemoglobin concentrations at term and in the postpartum period, but were at increased risk of Hb concentrations greater than 130 g/L during pregnancy, and at term.
Abstract: Background Iron and folic acid supplementation has been the preferred intervention to improve iron stores and prevent anaemia among pregnant women, and it is thought to improve other maternal and birth outcomes. Objectives To assess the effects of daily oral iron supplements for pregnant women, either alone or in conjunction with folic acid, or with other vitamins and minerals as a public health intervention in antenatal care. Search methods We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (10 January 2015). We also searched the WHO International Clinical Trials Registry Platform (ICTRP) (26 February 2015) and contacted relevant organisations for the identification of ongoing and unpublished studies (26 February 2015) . Selection criteria Randomised or quasi-randomised trials evaluating the effects of oral preventive supplementation with daily iron, iron + folic acid or iron + other vitamins and minerals during pregnancy. Data collection and analysis We assessed the methodological quality of trials using standard Cochrane criteria. Two review authors independently assessed trial eligibility, extracted data and conducted checks for accuracy. We used the GRADE approach to assess the quality of the evidence for primary outcomes.We anticipated high heterogeneity among trials and we pooled trial results using a random-effects model and were cautious in our interpretation of the pooled results: the random-effects model gives the average treatment effect. Main results We included 61 trials. Forty-four trials, involving 43,274 women, contributed data and compared the effects of daily oral supplements containing iron versus no iron or placebo.Preventive iron supplementation reduced maternal anaemia at term by 70% (risk ratio (RR) 0.30; 95% confidence interval (CI) 0.19 to 0.46, 14 trials, 2199 women, low quality evidence), iron-deficiency anaemia at term (RR 0.33; 95% CI 0.16 to 0.69, six trials, 1088 women), and iron deficiency at term by 57% (RR 0.43; 95% CI 0.27 to 0.66, seven trials, 1256 women, low quality evidence). There were no clear differences between groups for severe anaemia in the second or third trimester, or maternal infection during pregnancy (RR 0.22; 95% CI 0.01 to 3.20, nine trials, 2125 women, very low quality evidence; and, RR 1.21; 95% CI 0.33 to 4.46; one trial, 727 women, low quality evidence, respectively), or maternal mortality (RR 0.33; 95% CI 0.01 to 8.19, two trials, 12,560 women, very low quality evidence), or reporting of side effects (RR 1.29; 95% CI 0.83 to 2.02, 11 trials, 2423 women, very low quality evidence). Women receiving iron were on average more likely to have higher haemoglobin (Hb) concentrations at term and in the postpartum period, but were at increased risk of Hb concentrations greater than 130 g/L during pregnancy, and at term.Compared with controls, women taking iron supplements less frequently had low birthweight newborns (8.4% versus 10.3%, average RR 0.84; 95% CI 0.69 to 1.03, 11 trials, 17,613 women, low quality evidence), and preterm babies (RR 0.93; 95% CI 0.84 to 1.03, 13 trials, 19,286 women, moderate quality evidence). They appeared to also deliver slightly heavier babies (mean difference (MD) 23.75; 95% CI -3.02 to 50.51, 15 trials, 18,590 women, moderate quality evidence). None of these results were statistically significant. There were no clear differences between groups for neonatal death (RR 0.91; 95% CI 0.71 to 1.18, four trials, 16,603 infants, low quality evidence), or congenital anomalies (RR 0.88, 95% CI 0.58 to 1.33, four trials, 14,636 infants, low quality evidence).Twenty-three studies were conducted in countries that in 2011 had some malaria risk in parts of the country. In some of these countries/territories, malaria is present only in certain areas or up to a particular altitude. Only two of these studies reported malaria outcomes. There is no evidence that iron supplementation increases placental malaria. For some outcomes heterogeneity was higher than 50%. Authors' conclusions Supplementation reduces the risk of maternal anaemia and iron deficiency in pregnancy but the positive effect on other maternal and infant outcomes is less clear. Implementation of iron supplementation recommendations may produce heterogeneous results depending on the populations' background risk for low birthweight and anaemia, as well as the level of adherence to the intervention.

401 citations

Journal ArticleDOI
TL;DR: A comprehensive checklist of items linked to relevant resources and tools that guideline developers could consider, without the expectation that every guideline would address each item, is compiled.
Abstract: Background: Although several tools to evaluate the credibility of health care guidelines exist, guidance on practical steps for developing guidelines is lacking. We systematically compiled a comprehensive checklist of items linked to relevant resources and tools that guideline developers could consider, without the expectation that every guideline would address each item. Methods: We searched data sources, including manuals of international guideline developers, literature on guidelines for guidelines (with a focus on methodology reports from international and national agencies, and professional societies) and recent articles providing systematic guidance. We reviewed these sources in duplicate, extracted items for the checklist using a sensitive approach and developed overarching topics relevant to guidelines. In an iterative process, we reviewed items for duplication and omissions and involved experts in guideline development for revisions and suggestions for items to be added. Results: We developed a checklist with 18 topics and 146 items and a webpage to facilitate its use by guideline developers. The topics and included items cover all stages of the guideline enterprise, from the planning and formulation of guidelines, to their implementation and evaluation. The final checklist includes links to training materials as well as resources with suggested methodology for applying the items. Interpretation: The checklist will serve as a resource for guideline developers. Consideration of items on the checklist will support the development, implementation and evaluation of guidelines. We will use crowdsourcing to revise the checklist and keep it up to date.

400 citations

Journal ArticleDOI
TL;DR: There was asymmetric distribution of growth of EFW: a slightly wider distribution among the lower percentiles during early weeks shifted to a notably expanded distribution of the higher percentiles in late pregnancy.
Abstract: Background Perinatal mortality and morbidity continue to be major global health challenges strongly associated with prematurity and reduced fetal growth, an issue of further interest given the mounting evidence that fetal growth in general is linked to degrees of risk of common noncommunicable diseases in adulthood. Against this background, WHO made it a high priority to provide the present fetal growth charts for estimated fetal weight (EFW) and common ultrasound biometric measurements intended for worldwide use. Methods and Findings We conducted a multinational prospective observational longitudinal study of fetal growth in low-risk singleton pregnancies of women of high or middle socioeconomic status and without known environmental constraints on fetal growth. Centers in ten countries (Argentina, Brazil, Democratic Republic of the Congo, Denmark, Egypt, France, Germany, India, Norway, and Thailand) recruited participants who had reliable information on last menstrual period and gestational age confirmed by crown–rump length measured at 8–13 wk of gestation. Participants had anthropometric and nutritional assessments and seven scheduled ultrasound examinations during pregnancy. Fifty-two participants withdrew consent, and 1,387 participated in the study. At study entry, median maternal age was 28 y (interquartile range [IQR] 25–31), median height was 162 cm (IQR 157–168), median weight was 61 kg (IQR 55–68), 58% of the women were nulliparous, and median daily caloric intake was 1,840 cal (IQR 1,487–2,222). The median pregnancy duration was 39 wk (IQR 38–40) although there were significant differences between countries, the largest difference being 12 d (95% CI 8–16). The median birthweight was 3,300 g (IQR 2,980–3,615). There were differences in birthweight between countries, e.g., India had significantly smaller neonates than the other countries, even after adjusting for gestational age. Thirty-one women had a miscarriage, and three fetuses had intrauterine death. The 8,203 sets of ultrasound measurements were scrutinized for outliers and leverage points, and those measurements taken at 14 to 40 wk were selected for analysis. A total of 7,924 sets of ultrasound measurements were analyzed by quantile regression to establish longitudinal reference intervals for fetal head circumference, biparietal diameter, humerus length, abdominal circumference, femur length and its ratio with head circumference and with biparietal diameter, and EFW. There was asymmetric distribution of growth of EFW: a slightly wider distribution among the lower percentiles during early weeks shifted to a notably expanded distribution of the higher percentiles in late pregnancy. Male fetuses were larger than female fetuses as measured by EFW, but the disparity was smaller in the lower quantiles of the distribution (3.5%) and larger in the upper quantiles (4.5%). Maternal age and maternal height were associated with a positive effect on EFW, particularly in the lower tail of the distribution, of the order of 2% to 3% for each additional 10 y of age of the mother and 1% to 2% for each additional 10 cm of height. Maternal weight was associated with a small positive effect on EFW, especially in the higher tail of the distribution, of the order of 1.0% to 1.5% for each additional 10 kg of bodyweight of the mother. Parous women had heavier fetuses than nulliparous women, with the disparity being greater in the lower quantiles of the distribution, of the order of 1% to 1.5%, and diminishing in the upper quantiles. There were also significant differences in growth of EFW between countries. In spite of the multinational nature of the study, sample size is a limiting factor for generalization of the charts. Conclusions This study provides WHO fetal growth charts for EFW and common ultrasound biometric measurements, and shows variation between different parts of the world.

400 citations

Journal ArticleDOI
TL;DR: There is a need to expand the evidence base on comorbidity, particularly in low-income countries, and policies that reduce the use of substances are likely to reduce the prevalence of mental disorders.
Abstract: This paper reviews some major epidemiological studies undertaken in high-income countries during the last 15 years which have reported the prevalence of mental disorders and substance use disorders and their relationship. Comorbidity between mental and substance use disorders is highly prevalent across countries. In general, people with a substance use disorder had higher comorbid rates of mental disorders than vice versa, and people with illicit drug disorders had the highest rates of comorbid mental disorders. There is a strong direct association between the magnitude of comorbidity and the severity of substance use disorders. While causal pathways differ across substances and disorders, there is evidence that alcohol is a casual factor for depression, in some European countries up to 10% of male depression. Policies that reduce the use of substances are likely to reduce the prevalence of mental disorders. Treatment should be available in an integrated fashion for both mental and substance use disorders. There is a need to expand the evidence base on comorbidity, particularly in low-income countries.

399 citations


Authors

Showing all 13385 results

NameH-indexPapersCitations
Christopher J L Murray209754310329
Michael Marmot1931147170338
Didier Raoult1733267153016
Alan D. Lopez172863259291
Zulfiqar A Bhutta1651231169329
Simon I. Hay165557153307
Robert G. Webster15884390776
Ali H. Mokdad156634160599
Matthias Egger152901184176
Paolo Boffetta148145593876
Jean Bousquet145128896769
Igor Rudan142658103659
Holger J. Schünemann141810113169
Richard M. Myers134496137791
Majid Ezzati133443137171
Network Information
Related Institutions (5)
Centers for Disease Control and Prevention
82.5K papers, 4.4M citations

92% related

Public Health Research Institute
8.1K papers, 276.9K citations

91% related

Liverpool School of Tropical Medicine
8.6K papers, 325K citations

90% related

Norwegian Institute of Public Health
8.1K papers, 362.8K citations

90% related

University of London
88K papers, 4M citations

89% related

Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
202319
202279
20211,792
20201,612
20191,402
20181,360