Samuel Danso

Bio: Samuel Danso is an academic researcher from University of Edinburgh. The author has contributed to research in topics: Population & Verbal autopsy. The author has an hindex of 16, co-authored 46 publications receiving 1036 citations. Previous affiliations of Samuel Danso include Ministry of Health (Ghana) & University of London.

Effect of the Newhints home-visits intervention on neonatal mortality rate and care practices in Ghana: a cluster randomised controlled trial

Abstract: Summary Background In 2009, on the basis of promising evidence from trials in south Asia, WHO and UNICEF issued a joint statement about home visits as a strategy to improve newborn survival. In the Newhints trial, we aimed to test this home-visits strategy in sub-Saharan Africa by assessing the effect on all-cause neonatal mortality rate (NMR) and essential newborn-care practices. Methods The Newhints cluster randomised trial was undertaken in 98 zones in seven districts in the Brong Ahafo Region, Ghana. 49 zones were randomly assigned to the Newhints intervention and 49 to the control intervention by use of restricted randomisation with stratification to ensure comparability between interventions. Community-based surveillance volunteers (CBSVs) in Newhints zones were trained to identify pregnant women in their community and to make two home visits during pregnancy and three in the first week of life to promote essential newborn-care practices, weigh and assess babies for danger signs, and refer as necessary. Primary outcomes were NMR and coverage of key essential newborn-care practices. Analyses were by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00623337. Findings 16 168 (99%) of 16 329 deliveries between November, 2008, and December, 2009, were livebirths; the status at 1 month was known for 15 619 (97%) livebirths. 482 neonatal deaths were recorded. Coverage data were available from 6029 women in Newhints zones; of these 4358 (72%) reported having CBSV visits during pregnancy and 3815 (63%) reported having postnatal visits. This coverage increased substantially from June, 2009, after the introduction of new implementation strategies and reached almost 90% for pregnancy visits by the end of the trial and 75% for postnatal visits. The Newhints intervention significantly increased coverage of key essential newborn-care behaviours, except for four or more antenatal-care visits (5975 [76%] of 7859 vs 5988 [74%] of 8121, respectively; relative risk 1·02, 95% CI 0·96–1·09; p=0·52) and baby delivered in a facility (5373 [68%] vs 5539 [68%], respectively; 0·97, 0·81–1·14; p=0·69). The largest increase was for care-seeking, with 102 (77%) of 132 sick babies in Newhints zones taken to a hospital or clinic compared with 77 (55%) of 139 in control zones (1·43, 1·17–1·76; p=0·001). Increases were also noted in bednet use during pregnancy (5398 [69%] of 7859 vs 5135 [63%] of 8121, respectively; 1·12, 1·03–1·21; p=0·005), money saved for delivery or emergency (5730 [86%] of 6681 vs 5525 [80%] of 6941, respectively; 1·09, 1·05–1·12; p vs 2061 [30%], respectively; 1·30, 1·12–1·49; p=0·0004), birth assistant for home delivery washed hands with soap (1853 [93%] of 1992 vs 1817 [87%] of 2091, respectively; 1·05, 1·02–1·09; p=0·001), initiation of breastfeeding in less than 1 h of birth (3743 [49%] of 7673 vs 3280 [41%] of 7921, respectively; 1·22, 1·07–1·40; p=0·004), skin to skin contact (3355 [44%] vs 1931 [24%], respectively; 2·30, 1·85–2·87; p=0·0002), first bath delayed for longer than 6 h (3131 [41%] vs 2269 [29%], respectively; 1·65, 1·27–2·13; p vs 1091 [80%] of 1371; 1·10, 1·04–1·16; p=0·001), and baby sleeping under bednet for 8–56 days (4548 [79%] of 5756 vs 4291 [73%] of 5846; 1·09, 1·03–1·15; p=0·002). There were 230 neonatal deaths in the Newhints zones compared with 252 in the control zones. The overall NMRs per 1000 livebirths were 29·8 and 31·9, respectively (0·92, 0·75–1·12; p=0·405). Interpretation The reduction in NMR with Newhints is consistent with the reductions achieved in three trials undertaken in programme settings in south Asia. Because there is no suggestion of any heterogeneity (p=0·850) between these trials and Newhints, the meta-analysis summary estimate of a reduction of 12% (95% CI 5–18) provides the best evidence for the likely effect of the home-visits strategy delivered within programmes in sub-Saharan Africa and in south Asia. Improvements in the quality of delivery and neonatal care in health facilities and development of innovative, effective strategies to increase coverage of home visits on the day of birth could lead to the achievement of more substantial reductions. Funding WHO, Bill & Melinda Gates Foundation, and UK Department for International Development.

Machine learning of neuroimaging for assisted diagnosis of cognitive impairment and dementia: A systematic review

Abstract: Introduction Advanced machine learning methods might help to identify dementia risk from neuroimaging, but their accuracy to date is unclear. Methods We systematically reviewed the literature, 2006 to late 2016, for machine learning studies differentiating healthy aging from dementia of various types, assessing study quality, and comparing accuracy at different disease boundaries. Results Of 111 relevant studies, most assessed Alzheimer's disease versus healthy controls, using AD Neuroimaging Initiative data, support vector machines, and only T1-weighted sequences. Accuracy was highest for differentiating Alzheimer's disease from healthy controls and poor for differentiating healthy controls versus mild cognitive impairment versus Alzheimer's disease or mild cognitive impairment converters versus nonconverters. Accuracy increased using combined data types, but not by data source, sample size, or machine learning method. Discussion Machine learning does not differentiate clinically relevant disease categories yet. More diverse data sets, combinations of different types of data, and close clinical integration of machine learning would help to advance the field.

Effect of vitamin A supplementation in women of reproductive age on maternal survival in Ghana (ObaapaVitA): a cluster-randomised, placebo-controlled trial

Abstract: Summary Background A previous trial in Nepal showed that supplementation with vitamin A or its precursor (betacarotene) in women of reproductive age reduced pregnancy-related mortality by 44% (95% CI 16–63). We assessed the effect of vitamin A supplementation in women in Ghana. Methods ObaapaVitA was a cluster-randomised, double-blind, placebo-controlled trial undertaken in seven districts in Brong Ahafo Region in Ghana. The trial area was divided into 1086 small geographical clusters of compounds with fieldwork areas consisting of four contiguous clusters. All women of reproductive age (15–45 years) who gave informed consent and who planned to remain in the area for at least 3 months were recruited. Participants were randomly assigned by cluster of residence to receive a vitamin A supplement (25 000 IU retinol equivalents) or placebo capsule orally once every week. Randomisation was blocked and based on an independent, computer-generated list of numbers, with two clusters in each fieldwork area allocated to vitamin A supplementation and two to placebo. Capsules were distributed during home visits undertaken every 4 weeks, when data were gathered on pregnancies, births, and deaths. Primary outcomes were pregnancy-related mortality and all-cause female mortality. Cause of death was established by verbal post mortems. Analysis was by intention to treat (ITT) with random-effects regression to account for the cluster-randomised design. Adverse events were synonymous with the trial outcomes. This trial is registered with ClinicalTrials.gov, number NCT00211341. Findings 544 clusters (104 484 women) were randomly assigned to vitamin A supplementation and 542 clusters (103 297 women) were assigned to placebo. The main reason for participant drop out was migration out of the study area. In the ITT analysis, there were 39 601 pregnancies and 138 pregnancy-related deaths in the vitamin A supplementation group (348 deaths per 100 000 pregnancies) compared with 39 234 pregnancies and 148 pregnancy-related deaths in the placebo group (377 per 100 000 pregnancies); adjusted odds ratio 0·92, 95% CI 0·73–1·17; p=0·51. 1326 women died in 292 560 woman-years in the vitamin A supplementation group (453 deaths per 100 000 years) compared with 1298 deaths in 289 310 woman-years in the placebo group (449 per 100 000 years); adjusted rate ratio 1·01, 0·93–1·09; p=0·85. Interpretation The body of evidence, although limited, does not support inclusion of vitamin A supplementation for women in either safe motherhood or child survival strategies. Funding UK Department for International Development, and USAID.

Aetiology of stillbirths and neonatal deaths in rural Ghana: implications for health programming in developing countries.

Abstract: In developing countries many stillbirths and neonatal deaths occur at home and cause of death is not recorded by national health information systems. A community-level verbal autopsy tool was used to obtain data on the aetiology of stillbirths and neonatal deaths in rural Ghana. Objectives were to describe the timing and distribution of causes of stillbirths and neonatal deaths according to site of death (health facility or home). Data were collected from 1 January 2003 to 30 June 2004; 20,317 deliveries, 696 stillbirths and 623 neonatal deaths occurred over that time. Most deaths occurred in the antepartum period (28 weeks gestation to the onset of labour) (33.0%). However, the highest risk periods were during labour and delivery (intrapartum period) and the first day of life. Infections were a major cause of death in the antepartum (10.1%) and neonatal (40.3%) periods. The most important cause of intrapartum death was obstetric complications (59.3%). There were significantly fewer neonatal deaths resulting from birth asphyxia in the home than in the health facilities and more deaths from infection. Only 59 (20.7%) mothers of neonates who died at home reported that they sought care from an appropriate health care provider (doctor, nurse or health facility) during their baby's illness. The results from this study highlight the importance of studying community-level data in developing countries and the high risk of intrapartum stillbirths and infectious diseases in the rural African mother and neonate. Community-level interventions are urgently needed, especially interventions that reduce intrapartum deaths and infection rates in the mother and infant.

Diagnostic accuracy of verbal autopsies in ascertaining the causes of stillbirths and neonatal deaths in rural Ghana.

Abstract: This study evaluated the diagnostic accuracy of a verbal autopsy (VA) tool in ascertaining the causes of stillbirths and neonatal deaths in rural Ghana and was nested within a community-based maternal vitamin A supplementation trial (ObaapaVitA trial). All stillbirths and neonatal deaths between 1 January 2003 and 30 June 2004 were prospectively included. Community VAs were carried out within 6 months of death and were classified with a primary cause of death by three experienced paediatricans. The reference standard diagnosis was obtained by the study paediatrician in 4 district hospitals in the study area. There were 20 317 deliveries, 661 stillbirths and 590 neonatal deaths with a VA diagnosis in the study population. A total of 311 stillbirths and 191 neonatal deaths had both a VA and a hospital reference standard diagnosis. The VA performed poorly for stillbirth diagnoses such as congenital abnormalities and maternal haemorrhage. Accuracy was higher for intrapartum obstetric complications and antepartum maternal disease. For neonatal deaths, sensitivity was >60% for all major causes; specificity was 76% for birth asphyxia but >85% for prematurity and infection. Overall, VA diagnostic accuracy was higher than expected in this rural African setting. Our classification system was based on the expected public health importance of the individual causes of death, differing implications for intervention and the ability to distinguish between the individual causes in low-resource settings. We believe this system was easier to use than traditional approaches and resulted in high precision and accuracy. However, further simplifications are needed to allow use of the World Health Organisation VA in routine child health programmes. The diagnostic accuracy of the VA tool should also be assessed in other regions and in multicentre studies.

Maternal and child undernutrition and overweight in low-income and middle-income countries

Abstract: Maternal and child malnutrition in low-income and middle-income countries encompasses both undernutrition and a growing problem with overweight and obesity. Low body-mass index, indicative of maternal undernutrition, has declined somewhat in the past two decades but continues to be prevalent in Asia and Africa. Prevalence of maternal overweight has had a steady increase since 1980 and exceeds that of underweight in all regions. Prevalence of stunting of linear growth of children younger than 5 years has decreased during the past two decades, but is higher in south Asia and sub-Saharan Africa than elsewhere and globally affected at least 165 million children in 2011; wasting affected at least 52 million children. Deficiencies of vitamin A and zinc result in deaths; deficiencies of iodine and iron, together with stunting, can contribute to children not reaching their developmental potential. Maternal undernutrition contributes to fetal growth restriction, which increases the risk of neonatal deaths and, for survivors, of stunting by 2 years of age. Suboptimum breastfeeding results in an increased risk for mortality in the first 2 years of life. We estimate that undernutrition in the aggregate--including fetal growth restriction, stunting, wasting, and deficiencies of vitamin A and zinc along with suboptimum breastfeeding--is a cause of 3·1 million child deaths annually or 45% of all child deaths in 2011. Maternal overweight and obesity result in increased maternal morbidity and infant mortality. Childhood overweight is becoming an increasingly important contributor to adult obesity, diabetes, and non-communicable diseases. The high present and future disease burden caused by malnutrition in women of reproductive age, pregnancy, and children in the first 2 years of life should lead to interventions focused on these groups.

CONSORT statement: extension to cluster randomised trials

Abstract: The Consolidated Standards of Reporting Trials (CONSORT) statement was developed to improve the reporting of randomised controlled trials. It was initially published in 1996 and focused on the reporting of parallel group randomised controlled trials. The statement was revised in 2001, with a further update in 2010. A separate CONSORT statement for the reporting of abstracts was published in 2008. In earlier papers we considered the implications of the 2001 version of the CONSORT statement for the reporting of cluster randomised trial. In this paper we provide updated and extended guidance, based on the 2010 version of the CONSORT statement and the 2008 CONSORT statement for the reporting of abstracts.

Identifying the women at risk of antenatal anxiety and depression: A systematic review.

Abstract: Background Pregnancy is a time of increased vulnerability for the development of anxiety and depression. This systematic review aims to identify the main risk factors involved in the onset of antenatal anxiety and depression.