Informal Settlements In Nairobi Research Articles

Family influences on child nutritional outcomes in Nairobi's informal settlements.

BackgroundImproving child nutritional status is an important step towards achieving the Sustainable Development Goals 2 and 3 in developing countries. Most child nutrition interventions in these countries remain variably effective because the strategies often target the child's mother/caregiver and give limited attention to other household members. Quantitative studies have identified individual level factors, such as mother and child attributes, influencing child nutritional outcomes.MethodsWe used a qualitative approach to explore the influence of household members on child feeding, in particular, the roles of grandmothers and fathers, in two Nairobi informal settlements. Using in‐depth interviews, we collected data from mothers of under‐five children, grandmothers, and fathers from the same households.ResultsOur findings illustrate that poverty is a root cause of poor nutrition. We found that mothers are not the sole decision makers within the household regarding the feeding of their children, as grandmothers appear to play key roles. Even in urban informal settlements, three‐generation households exist and must be taken into account. Fathers, however, are described as providers of food and are rarely involved in decision making around child feeding. Lastly, we illustrate that promotion of exclusive breastfeeding for 6 months, as recommended by the World Health Organization, is hard to achieve in this community.ConclusionsThese findings call for a more holistic and inclusive approach for tackling suboptimal feeding in these communities by addressing poverty, targeting both mothers and grandmothers in child nutrition strategies, and promoting environments that support improved feeding practices such as home‐based support for breastfeeding and other baby‐friendly initiatives.

Neighborhood Disorganization and Women’s Sanitation Utilization Practices in Mathare Valley, Kenya

Approximately, 2.4 billion people, globally, lack access to safe toilets. The burden of this deficiency falls disproportionately on women living in informal settlements in developing countries. While there is a growing body of literature looking at the factors influencing women’s sanitation behavior, little is known about the role of the neighborhood environment. This study sought to explore this issue using data from a 2016 mixed-methods study focused on women in Mathare Valley informal settlement in Nairobi, Kenya. Qualitative and quantitative data were used to analyze the role of neighborhood disorganization in the relationship between women’s sanitation-related stressors and their sanitation behaviors (utilization). Findings suggest that neighborhood disorganization is inextricably linked to women’s daily sanitation behaviors and the stressors that are associated with those behaviors. These results suggest that the health and safety of neighborhood environments may be critical factors in the future success of sanitation-related interventions and policies.

Analysing child linear growth trajectories among under-5 children in two Nairobi informal settlements.

We sought to identify factors associated with linear growth among under-5 children in two urban informal settlements in Nairobi. We used longitudinal data for the period 2007-2012 from under-5 children recruited in the two sites between birth and 23 months and followed up until they reached 5 years of age. We fitted a generalized linear model on height-for-age Z-scores using the generalized estimating equations method to model linear growth trajectories among under-5 children. Known for its flexibility, the model provides strong parameter estimates and accounts for correlated observations on the same child. Two urban informal settlements in Nairobi, Kenya.ParticipantsUnder-5 children (n 1917) and their mothers (n 1679). The findings show that child weight at birth, exclusive breast-feeding and immunization status were key determinants of linear growth among under-5 children. Additionally, maternal characteristics (mother's age, marital status) and household-level factors (socio-economic status, size of household) were significantly associated with child linear growth. There were biological differences in linear growth, as female children were more likely to grow faster than males. Finally, the model captured significant household-level effects to investigate further. Findings from the study point to the need to improve the targeting of child health programmes directed at the urban poor population in Nairobi. Specific modifiable determinants of child linear growth, particularly child weight at birth, exclusive breast-feeding, immunization status and mother's background characteristics, should be considered when designing interventions aiming at addressing child health inequities in these settings.

Biological and thermochemical conversion of human solid waste to soil amendments

Biological and thermochemical sanitization of source-separated human solid waste (HSW) are effective technologies for unsewered communities. While both methods are capable of fecal pathogen sterilization, the agronomically-beneficial properties of waste sanitized between methods remains unclear. Therefore, this study compared recovery and quality of soil amendments produced by compostation, torrefaction, and pyrolysis of HSW, established their financial value, and quantified tradeoffs between product value and conversion efficiency. Temperature and associated mass losses significantly affected the physical and chemical properties of thermochemically-treated HSW. Thermophilic composting, a biological sanitation method practiced in informal settlements in Nairobi, Kenya, produced an amendment that contained between 16 and 858-fold more plant-available nitrogen (N; 214.5 mg N/kg) than HSW pyrolyzed between 300 and 700 °C (0.2–15.2 mg N/kg). Conversely, HSW pyrolyzed at 600 °C had four-fold higher plant-available phosphorus (P; 3117 mg P/kg) and five-fold higher plant-available potassium (K; 7403 mg K/kg) than composted HSW (716 mg P/kg and 1462 mg K/kg). Wide variation between international fertilizer prices on the low end and regional East African prices on the high end resulted in broad-spaced quantiles for the value of agronomic components in HSW amendments. Phosphorus and K comprised a disproportionate amount of the value, 52–87%, compared to plant-available N, which contributed less than 2%. The total value of treated HSW, summed across all agronomic components per unit weight amendment, was greatest for thermochemically-treated HSW at 600 °C, averaging 220 USD/Mg, more than four-fold that of composted HSW, 53 USD/Mg. In contrast, torrefaction provided the highest monetary value per unit weight feedstock, 144 USD/Mg, as low heating temperatures engender minimal mass loss and higher nutrient densities per unit weight feedstock, compared to composted or pyrolyzed HSW. When benchmarked against total N, P, and K of eight commonly-applied organic amendments, including sewage-sludge (Milorganite), compost, and alfalfa meal, HSW pyrolyzed at 700 °C was of greatest value per unit weight of amendment, 365 USD/Mg, compared to 89 USD/Mg for composted HSW, and contained 2.9% total N (0.5 mg available N/kg), 3.1% total P (7640 mg available P/kg), 3.5% total K (17,671 mg available K/kg).

A mixed-methods study of women's sanitation utilization in informal settlements in Kenya.

While access to safe sanitation is a global issue, there are large disparities in access. Women living in informal settlements, in particular, are disproportionately affected by lack of access to sanitation. Without adequate sanitation, these women may resort to unsafe strategies to manage their sanitation needs, but limited research has focused specifically on this issue. Qualitative and quantitative data were collected from women in the Mathare informal settlement in Nairobi, Kenya in 2016. A latent class analysis (LCA) using the quantitative data yielded five distinct sanitation profiles (SP) among women in Mathare. In-depth interviews and sanitation walks with women added further detail about the characteristics of and motivations underlying each profile. Women’s sanitation profiles in these settlements are complex. A majority of women in this study utilized an unsafe method of disposal at least once in a 24-hour period that increased their risk of direct exposure to waste and harmful pathogens.

Revisiting the Sphere standards: comparing the revised Sphere standards to living standards in three urban informal settlements in Nairobi, Kenya

BackgroundHumanitarian actors have long used the Sphere Handbook and its minimum standards to guide operational practice. The new revision attempts to update these standards partly to address urban crises that have challenged the humanitarian system. Yet, these indicators have never been based on a substantial body of evidence or data from the varied living standards found in cities or specifically informal settlements. This study aims to contextualize the Sphere standards for urban populations by comparing a sample of the revised key indicators to living standards in three urban informal settlements of Nairobi, Kenya, during a non-crisis period to examine their relevance and applicability, and discuss the implications.MethodsRetrospective analysis of data sourced from randomized household surveys of three informal settlements in Nairobi across a range of living standards including a convenience sample of Sphere metrics is quantitatively compared to the newly revised Sphere standards.ResultsThe results show that while some standards are met, many of the urban poor in these settlements live far below the prescribed minimum standards across many key sectors including water, sanitation, shelter, and food security. The data also reveal variations between and within individual informal settlements.ConclusionThe Sphere standards are not informed enough by informality and remain largely aspirational for some populations and consensus rather than evidence-based. The revised handbook has made significant strides in highlighting the need for contextualization, market approaches, and incorporating stakeholder input. The new Sphere standards must be placed into context for use in the new urban agenda realigning humanitarian actions towards more locally contextualized and driven practice.

Exploring the complex relationship between women\u2019s sanitation practices and household diarrhea in the slums of Nairobi: a cross-sectional study

BackgroundDiarrheal disease kills over half a million people each year in sub-Saharan Africa; the majority are children under 5 years. About 58% of diarrhea cases are associated with poor water, sanitation, and hygiene—a critical issue for people living in informal settlements. In Kenya, 60% of Nairobi’s population lives in informal settlements; yet, there is a paucity of research exploring the relationship between water, sanitation and hygiene (WASH) conditions in these settlements and associated health outcomes.MethodsThe study examines characteristics of women’s WASH behaviors and environments as potential factors associated with household diarrhea in Mathare Valley Informal Settlement in Nairobi using cross-sectional survey data collected from 550 women.ResultsApproximately 17% of participants reported that at least one member of the household suffered from diarrhea in the previous 2 weeks—48% of the cases were children under five. Results from a logistic regression exploring factors associated with reports of household diarrhea suggest that women’s sanitation management strategies are associated with recent household diarrhea. Women who use toilets for defecation during the day, but rely on bags, buckets, or open defecation (OD) for urination during the day and for urination and defecation at night have over five time the odds of recent household diarrhea than women who use a toilet for all their sanitation needs. The odds of diarrhea were also higher for participants who walk up to 2 min to reach their toilets/sites for defecation and those who rely on water from taps inside buildings and plots. Odds were 62% lower for participants with clean toilets.ConclusionsFindings suggest that health targets to reduce the prevalence of diarrheal diseases in informal settlements may not be met unless particular attention is paid to the needs of women living in these environments.

Malnutrition, morbidity and infection in the informal settlements of Nairobi, Kenya: an epidemiological study

BackgroundMalnutrition constitutes one of the major public health challenges throughout the developing world. Urban poverty and malnutrition have been on the rise, with an increased rate of morbidity. We herein explore the relationship between infections and nutritional status and the related association with hygienic conditions as risk of infection in children residing in the slums of Nairobi.MethodsCase-control study based on a secondary analysis of quantitative data collected from a cluster randomized trial carried out in two slums of Nairobi. The following information about resident children were selected: babies’ anthropometric measurements, related life conditions, data on infant-feeding practices, food security, hygiene, immunization coverage and morbidity were collected and updated with structured questionnaires until 12 months of life. Prevalence of malnutrition was calculated, then both bivariate and multivariate analysis were used to explore the relationship between malnutrition and its determinants.ResultsThe study involved a total of 1119 babies registered at birth (51.28% male and 48.03% female infants). Overall the prevalence of malnutrition was high, with 26.3% of the children being stunted, 6.3% wasted and 13.16% underweight. Prevalence of wasting was higher in the first months of life, while in older children more case of stunting and underweight were captured. Wasted infants were significantly associated with common childhood illnesses: with cough and rapid breathing as well as with diarrhea (p-value< 0.05). Stunting was associated with hygienic conditions (p-value< 0.05 in households that did not perform any water treatment and for children that had a toilet within the house compound), immunization program and low-birth-weight. Moreover, regression analysis showed that significant determinants of stunting were sex and feeding practices. Underweight was significantly associated with socio-demographic factors.ConclusionsIn the specific environment where the study was conducted acute malnutrition is correlated with acute infections, while chronic malnutrition is more influenced by WASH conditions. Therefore, our findings suggest that one cannot separate infection and its risk factors as determinants of the whole malnutrition burden.

Participatory mapping and food‐centred justice in informal settlements in Nairobi, Kenya

Food vendors are pivotal in the local food system of most low‐income informal settlements in Nairobi, Kenya, despite being seen as an obstruction and as agents of disease and filth by city authorities. This paper explores the geography of these foodscapes – defined as public sites of food production and consumption – in selected low‐income settlements in Nairobi, focusing on the interaction of food vendors with their surrounding environment and infrastructure services. The research uses participatory geographic information system tools, including food mapping with mobile apps and high‐resolution community aerial views with balloon mapping, to capture and contextualise local knowledge. The community mappers collected data on 660 vendors from 18 villages in Kibera, Mathare, and Mukuru, and situated them on multi‐layered synoptic geographic overviews for each settlement. The resulting data on hazardous areas in relation to food spaces and infrastructure provision allowed local communities to prioritise areas for regular clean‐up activities and assisted advocacy to improve these places in cooperation with local authorities. These multiple visual representations of foodscapes make local food vendors, and the risks they face, visible for the first time. Reframing their “right to safe food and environment” from a social and environmental justice perspective allows local communities to put their experiences, knowledge, and challenges faced at the forefront of urban development planning, policy, and practice.

Magnitude and predictors of normal-weight central obesity– the AWI-Gen study findings

ABSTRACTBackground: Normal-weight central obesity is associated with higher mortality than general obesity as defined by body mass index, particularly in the absence of central fat distribution.Objective: The aim of this study was to examine the magnitude and predictors of normal-weight central obesity in an urban informal settlement setting in Kenya.Methods: We used data from the AWI-Gen study, a cross-sectional survey targeting randomly selected consenting adults between the ages of 40–60 in two urban informal settlements of Nairobi between 2014 and 2016. Central obesity was determined using waist circumference, waist to hip ratio, visceral fat thickness, and subcutaneous fat thickness. General obesity was determined using body mass index (BMI).Results: About 20.0% of participants in the study had general obesity. The prevalence of central obesity as measured by waist circumference was 52.0%, by waist-to-hip ratio was 53.5%, by visceral fat thickness was 32.4% and by subcutaneous fat thickness was 49.2%. The prevalence of normal-weight central obesity in the study population was highest when measured by waist to hip ratio (38.1%) and lowest when measured by visceral fat thickness (18.1%). Factors associated with normal-weight central obesity as assesses by waist circumference were being female, of older age, and in full-time employment. Older age was associated with normal-weight central obesity as assessed by waist to hip ratio.Conclusion: The findings highlight a significant prevalence of normal-weight central obesity among adults in a poor urban setting in Kenya, pointing to women as a key target group for focused interventions. Longitudinal studies are needed to establish whether there is a link between normal-weight central obesity and mortality in such settings as has been found in other settings.

Mechanisms associated with maternal adverse childhood experiences on offspring\u2019s mental health in Nairobi informal settlements: a mediational model testing approach

BackgroundAdverse childhood experiences (ACEs) is a significant public health and social welfare problem in low-and middle income countries (LMICs). However, most ACEs research is based on developed countries, and little is known about mechanisms of early ACEs on adulthood health and offspring’s wellbeing for populations in LMICs. This area is needed to guide social welfare policy and intervention service planning. This study addresses these research gaps by examining patterns of ACEs and understanding the role of ACEs on adulthood health (i.e., physical, mental health, experience of underage pregnancy) and offspring’s mental health in Kenya. The study was guided by an Integrated Family Stress and Adverse Childhood Experiences Mediation Framework.MethodsThree hundred ninety four mothers from two informal communities in Kariobangi and Kangemi in Nairobi were included in this study. The Adverse Childhood Experiences International Questionnaire (ACE-IQ), the Kessler Psychological Distress Scale (K10), Overall Health and Quality of Life items, and Child Behavior Checklist were used to study research questions. Data was gathered through a one-time interview with mothers. Structural Equational Modeling (SEM) was applied for mediational mechanism testing.ResultsAmong 13 ACE areas, most mothers experienced multiple adversity during their childhood (Mean (SD) = 4.93 (2.52)), with household member treated violently (75%) as the most common ACE. SEM results showedthat all domains of ACEs were associated with some aspects of maternal health, and all three domains of maternal health (maternal mental health, physical health, and adolescent pregnancy) were significantly associated with development of offspring’s mental health problems.ConclusionACEs are highly prevalent in Kenyan informal settlements. Consistent with cross cultural literature on family stress model, maternal ACEs are robust predictors for poor child mental health. Preventive interventions for child mental health need to address maternal adverse childhood traumatic experiences as well as their current health in order to effectively promote child mental health.

Shifting parental roles, caregiving practices and the face of child development in low resource informal settlements of Nairobi: experiences of community health workers and school teachers

Approximately, 42% of the Kenyan population live below the poverty line. Rapid growth and urbanization of Kenya’s population have resulted in a changing poverty and food security environment in high-density urban areas. Lack of basic food needs in Kenya affects approximately 34.8% rural population and 7.6% of its urban population. Using multi-community stakeholders such as teachers and community health workers (CHWs), this paper examined food insecurity and its consequences on caregiving practices and child development. A qualitative study design was utilized. Key informant interviews and focused-group discussions with four primary school teachers and three CHWs and a nurse in-charge working within Kariobangi and Kangemi were applied to elicit various perspectives from family-, school- and community-level challenges that influence caregiving practices and child development. Grounded theory method was applied for qualitative data sifting and thematic analysis. Our findings exposed various challenges at the school, family and the community levels that affect caregiving practices and consequent child development. School-level challenges included lack of adequate amenities for effective learning, food insecurity, absenteeism and mental health challenges. Family-level barriers included lack of parenting skills, financial constraints, domestic violence and lack of social support, while community challenges such as unemployment, poor living conditions, cultural practices, lack of social support and poor community follow-up mechanisms contributed to poor parenting practices and child development. Parenting practices and holistic child development strategies in resource poor settings should focus on parenting skills, food security, quality education and addressing parents and children’s mental health challenges.

Show me (more than) the money! Assessing the social and psychological dimensions to energy efficient lighting in Kenya

Despite economic, social and environmental benefits, the uptake of energy-saving compact fluorescent lamp light bulbs (CFLs) in Kibera, an informal settlement in Nairobi, remains low. We conducted a randomized controlled field experiment involving 651 Kibera residents assessing whether the joint impact of monetary incentives and behavioral interventions (pre-commitment and simplified information highlighting CFL benefits) could increase CFL uptake. A monetary incentive covering the incremental cost of a CFL compared to an incandescent bulb positively impacted uptake. However, adding simplified information more than tripled the impact of the monetary incentive alone, resulting in a remarkable uptake rate of about 84%. While a post endline survey conducted two years following the administration of the randomized control trial does not find lasting effects, this paper provides evidence for additional behavioral hypotheses in developing countries, also assessing the contribution of intelligence and measured discount rates to account for potential household present bias. It is to date the only intervention of its type that explores the extent to which behavioral interventions can complement monetary incentives.

Women’s sanitation practices in informal settlements: A multi-level analysis of factors influencing utilisation in Nairobi, Kenya

ABSTRACTFor decades, countries throughout the world have failed to meet sanitation-related development goals. Access to safe sanitation is undeniably linked to improved health outcomes; yet, 2.4 billion people, globally, still lack access. The persistent failure to meet sanitation goals suggests that our understanding of the factors that influence sustainable sanitation access and utilisation is incomplete. Despite growing availability of toilets in informal settlements, there is evidence that women, in particular, may adopt other strategies for managing their sanitation needs. Empirical data documenting the motivations underlying such practices in sub-Saharan Africa are limited. This study uses cross-sectional data collected in 2016 from women in Mathare Valley Informal Settlement in Nairobi, Kenya. Boosted and logistic regressions were used to investigate which factors were associated with women’s common sanitation patterns. Lack of privacy and insecurity at toilets and neighbourhood disorganisation emerged as important factors – particularly for women who reported regularly using buckets or plastic bags for urination/defecation. These findings suggest that availability of toilets may not be enough to eliminate sanitation-related health risks in informal settlements. Future interventions may need to address other barriers to sanitation access if sustainable gains in this important public health area are to be achieved.

Not just any toilet – women’s solutions to sanitation in informal settlements in Nairobi

ABSTRACTEvidence suggests sanitation development is more effective when women are involved. The purpose of this study was to provide women with an opportunity to share their perspectives and solutions to sanitation in informal settlements. Data were collected through 55 in-depth interviews with women in Mathare Valley informal settlement in Nairobi, Kenya. The most common solution was to build more toilets, but women had a variety of suggestions – including gender-specific solutions. Findings from this study suggest that it is imperative to start addressing women-specific burdens associated with sanitation in informal settlements.

Method‐Specific Attributes that Influence Choice of Future Contraception Among Married Women in Nairobi's Informal Settlements

Despite an extensive evidence base on contraceptive method choice, it remains uncertain which factors are most influential in predisposing women toward certain methods and against others. This paper addresses this gap in knowledge by making use of rarely‐measured perceptions about specific methods, perceived social network experience of methods, and women's own past experiences using specific methods. We draw on baseline data from the project, “Improving Measurement of Unintended Pregnancy and Unmet Need for Family Planning.” Using conditional logit analysis, we ascertain which perceived method‐specific attributes, including past experience of methods by women themselves and by their friends, predict preferred future contraceptive method among 317 women living in Nairobi slums who are using no method but intend to start in the next 12 months. Results show that satisfaction with past use, positive experience of use by a woman's social network, husband/partner's approval, lack of interference with menses, and perception of safety for long term use were all associated with choice of a future method.

Drivers of women’s sanitation practices in informal settlements in sub-Saharan Africa: a qualitative study in Mathare Valley, Kenya

ABSTRACTDespite evidence suggesting women are disproportionately affected by the lack of adequate and safe sanitation facilities around the world, there is limited information about the factors that influence women’s ability to access and utilize sanitation, especially in sub-Saharan Africa. The purpose of this study was to explore factors influencing women’s sanitation practices in informal settlements in Nairobi, Kenya. Information from 55 in-depth interviews conducted in 2016 with 55 women in Mathare Valley Informal Settlement in Nairobi was used to carry out cross-case, thematic analysis of women’s common sanitation routines. Women identified neighborhood disorganization, fear of victimization, lack of privacy, and cleanliness/dirtiness of facilities as important factors in the choices they make about their sanitation practices. This suggests that future sanitation-related interventions and policies may need to consider strategies that focus not only on toilet provision or adoption but also on issues of space and community dynamics.

Support to Children’s Education in the Urban Slums of Nairobi: Community and Parents’ Perceptions with an Expanded Phase of an Education Intervention Program

The objective of this paper is to examine the perceptions of community elders and parents on their roles regarding support to their children’s education. Data come from the qualitative component of a baseline survey conducted in Korogocho and Viwandani, two urban informal settlements in Nairobi, Kenya. Data were collected in April-May 2016 through in-depth interviews, key informant interviews and focus group discussions. Results demonstrated that community elders internalized their role as the face of government in their respective communities, and enforced the implementation of education policies on behalf of all children. The community leaders also saw as part of their role the need to encourage parents to be active participants in their children’s education. Female parents with boys in the program perceived that parental monitoring and follow-up was important to ensure that their children attended school, and completed work assigned by the teachers, more so in Korogocho. Overall, parents recognized the importance of the role they played in their children’s education. This is a good entry point as parental support will ensure the success and sustainability of the intervention to improve educational outcomes for children, which in turn will help their children navigate the challenging period that adolescence presents.

Understanding HIV risks among adolescent girls and young women in informal settlements of Nairobi, Kenya: Lessons for DREAMS.

IntroductionHigh incidence of HIV infection among adolescent girls and young women (AGYW) has been attributed to the numerous and often layered vulnerabilities that they encounter including violence against women, unfavourable power relations that are worsened by age-disparate sexual relations, and limited access to sexual and reproductive health information and services. For AGYW living in urban informal settlements (slums), these vulnerabilities are compounded by pervasive poverty, fragmented social networks, and limited access to social services including health and education. In this paper, we assess sexual risk behaviours and their correlates among AGYW in two slum settlements in Nairobi, Kenya, prior to the implementation of interventions under the Determined Resilient Empowered AIDS-free Mentored and Safe (DREAMS) Partnership.MethodsWe drew on secondary data from the Transition to Adulthood study, the most recent representative study on adolescent sexual behaviour in the two settlements. The study was nested within the Nairobi Urban Health and Demographic Surveillance System (NUHDSS). Data were collected in 2009 from 1,390 AGYW aged 12–23 years. We estimated the proportions of AGYW reporting ever tested for HIV, condom use, multiple sexual partners and age-disparate sex by socio-demographic characteristics. “High risk” sexual behaviour was defined as a composite of these four variables and age at first sex. Multivariable regression analyses were performed to identify factors associated with risk behaviours.ResultsFifty-one percent of AGYW reported that they had ever tested for HIV and received results of their last test, with the proportion rising steeply by age (from 15% to 84% among those <15 years and 20–23 years, respectively). Of 578 AGYW who were sexually active in the 12 months preceding the survey, 26% reported using a condom at last sex, 4% had more than one sexual partner, and 26% had sex with men who were at least 5 years older or younger. All girls aged below 15 years who had sex (n = 9) had not used condoms at last sex. The likelihood of engaging in “high risk” sexual risk behaviour was higher among older AGYW (19–23 years), those in marital unions, of Luo ethnicity, out of school, living alone or with a friend (versus parents), living with spouse (versus parents), and those whose friends engaged in risky/anti-social behaviours. In contrast, Muslim faith, co-residence with both parents, and belonging to an organised social group were associated with lower odds of risky sexual behaviours.ConclusionOur study findings suggest that multifaceted approaches addressing the educational and social mediators of AGYW’s vulnerability and that also reach the people with whom AGYW live and interact, are needed to reduce the rapid onset of sexual risk during the adolescent years. There is a particular need to reach the youngest adolescent girls in poor urban settings, among whom condom use and awareness of HIV status is rare.

Urban systems complexity in sustainability and health: an interdisciplinary modelling study

BackgroundImproving urban health and sustainability raises complex questions that are best addressed through interdisciplinary and even transdisciplinary approaches, in which scientific research and analysis and stakeholder engagement have important roles. In this study we report pilot work in Nairobi (Kenya) and London (UK) that uses innovative methods to integrate qualitative and quantitative modelling to provide evidence to support policy development for health and sustainability in these cities. MethodsWe used two primary modelling methods, system dynamics and microsimulation, and sought to understand the value of these tools in combination to support policy decisions. System dynamics was used to establish an aggregated and non-linear causal map of the interconnections between diverse variables, and thus to gain insight into the policies and specific processes that need to be examined in further depth. System dynamics was a key tool for city-level stakeholder engagement. In part informed by the outcome of the system dynamics process, microsimulation was then used to quantify local effects on health of selected policy options. The results were mapped using geographic information systems methods. FindingsThe combination of system dynamics and microsimulation models provided a framework that enhanced collective knowledge about the interrelationships of policy decisions, funding, public awareness, and environmental and health effects. Our initial participatory system dynamics work on air pollution in Nairobi found that a combination of policies that focus on households and outdoor air could reduce household air pollution by about 50%, leaving it still above WHO-recommended levels. Yet, the investments in monitoring and health impact assessment have the potential to trigger reinforcing mechanisms that create synergies among existing policies and increase the return on investment. Preliminary 106-year microsimulation runs of the effects of PM2·5 in London revealed that anthropogenic emissions are associated with about 2300 incident cases of ischaemic heart disease annually. The two methods appeared to have valuable complementarity in their focus on aggregated dynamics at the policy level versus local policy effects. InterpretationThe use of system dynamics can produce a quantitative model of the policy implementation process, including the organisational barriers and opportunities for change. This can be extended to include aggregate outputs from other models to quantify a more holistic and high-level quantitative model of the dynamics of selected policy questions. Together, these methods can estimate regional environmental and local health effects of selected policies, but also inform about overcoming the barriers to these policies. FundingThe Housing in Nairobi's Informal Settlements—A Complex Urban System project funded by the Engineering and Physical Sciences Research Council, and the Complex Urban Systems for Sustainability and Health project funded by the Wellcome Trust.