Tag Archives: Slums

Private Providers are Consulted More Often than Public Providers in Slums

This finding comes from a number of studies across many parts of the world, including:

  1. India [1] – where private providers were both preferred over public providers and consulted more often. Private providers were more accessible in terms of distance from residence.
  2. Kenyan maternity care [2] – women preferred private over public providers, even though the private providers were rated as ‘inappropriate’ by government.
  3. Dhaka slums [3] – this is an important study because it divides health facilities according to Ahmed’s classification.[4] Most commonly consulted were pharmacies (43%), followed by government hospitals (14%), then private hospitals (4%), independent medical practitioners (3%), informal providers (3%), and traditional healers (1%). Dissatisfaction was highest with government hospitals (25%) and lowest with informal providers and pharmacists.
  4. Accra’s Sodom and Gomorrah slum [5] – the facilities accessed were similar to those in Dhaka; 61% pharmacies and 33% hospitals. In this study lack of insurance was a major factor limiting access, while distance from facilities was not.
  5. Mumbai slums [6] ­– this study did not look at pharmacies specifically, but overall local private providers were the most widely used facilities. The use of public providers rose in proportion to the seriousness of the disorder, from 15% at low categories to 42% for serious illness, and 60% for maternal health.

One important conclusion from the above literature is that facilities should be classified to capture those inside a slum and external to it, and that pharmacies / drug stores should have their own stratum and not be elided with informal or private providers. Private allopathic providers should be classified as medical, other registered health professional (nurse / medical officer), community health worker (with formal links to the public service), and informal non-qualified provider. In studies that cross slum boundaries, multi-level modelling should be used to allow for correlations within clusters and avoid an ecological fallacy / Simpson’s paradox.[7]

The above studies are all based on population/household-based questionnaires. Another Dhaka based study takes a different approach [8] – instead of asking people who live in slums where they go for their health care, Adams and colleagues mapped health facilities across six urban slums. They found that 80% of the 1041 facilities identified in their spatial survey were privately operated. Unlike NGO- and government-funded clinics, private health care delivery clinics operate in the evenings. Only a third of staff in these private clinics have a medical qualification. Overall, the ‘density’ of health delivery points across the six slums was 1.5 per 10,000 of population. The average distance to a major government hospital offering outpatient services was 3km.

In our NIHR Global Health Research Unit on Improving Health in Slums we will be combining supply-side surveys of facilities with demand-side household surveys of use and satisfaction. We plan to go further by examining the socio-political structures that have determined patterns of provision and that may facilitate or impede the future development of a more accessible and high-quality service. We will then model the costs and benefits of alternative logistically and politically viable options using an iterative approach. In developing these models we will work closely with residents of slums and with those who control the purse strings.

— Richard Lilford, CLAHRC WM Director


  1. Banerjee A, Bhawalkar JS, Jadhav SL, Rathod H, Khedkar DT. Access to Health Services Among Slum Dwellers in an Industrial Township and Surrounding Rural Areas: A Rapid Epidemiological Assessment. J Family Med Prim Care. 2012; 1(1): 20-6.
  2. Fotso JC & Mukiira C. Perceived quality of and access to care among poor urban women in Kenya and their utilization of delivery care: harnessing the potential of private clinics. Health Policy Plan. 2012; 27: 505-15.
  3. Khan MMH, Grübner O, Krämer A. Frequently used healthcare services in urban slums of Dhaka and adjacent rural areas and their determinants. J Public Health. 2012; 34(2): 261-71.
  4. Ahmed SM, Tomson G, Petzold M, Kabir ZN. Socioeconomic status overrides age and gender in determining health-seeking behaviour in rural Bangladesh. Bull World Health Organ. 2005; 83: 109-17.
  5. Owusu-Ansah F, Tagbor H, Afi Togbe M. Access to health in city slum dwellers: The case of Sodom and Gomorrah in Accra, Ghana. Afr J Prim Health Care Fam Med. 2016; 8(1): a822.
  6. Naydenova E, Raghu A, Ernst J, Sahariah SA, Gandhi M, Murphy G. Healthcare choices in Mumbai slums: A cross-sectional study. Wellcome Open Research 2017; 2: 115.
  7. Lilford RJ. Simpson’s Paradox and Discrimination. NIHR CLAHRC West Midlands News Blog. 28 November 2014.
  8. Adams AM, Islam R, Ahmed T. Who serves the urban poor? A geospatial and descriptive analysis of health services in slum settlements in Dhaka, Bangladesh. Health Policy Plan. 2015; 30: i32-45.

A Debt of Gratitude

For a while now I have been working closely with the African Population and Health Research Center (APHRC), which is based in Nairobi, Kenya. Last week’s issue of the Lancet carried an article on the APHRC, where they paid tribute to the outgoing director Alex Ezeh.[1] Alex had the wisdom to identify the enormous challenge posed by the rapidly expanding slums in African cities. He and his colleagues have produced ground-breaking work on health dynamics in urban slums. He was my inspiration, and I followed where he led. Together we compiled a Lancet Series summarising the state of the literature regarding the health of people living in the slums and proposing models to inform future research and policy making.[2] [3] These studies were recently summarised in the African version of ‘The Conversation’.[4] Our work has resulted in the award of a NIHR unit to study the provision of healthcare in slums in Africa and Asia. We have also secured funds from the Rockefeller foundation to run a Bellagio conference on statistical aspects of slum health. Currently, we are pursuing research into water and sanitation in slums, as this is one of the biggest problems leading to diarrhoea, stunting and death, especially in children under the age of five.

I have an enormous debt of gratitude to APHRC in general and Alex Ezeh in particular. I look forward to my ongoing association with Alex and to working very closely with his outstanding successor, Catherine Kyobutungi, who was also profiled in last week’s Lancet.[5]

— Richard Lilford, CLAHRC WM Director


    1. Green A. The African Population and Health Research Center. Lancet. 2017; 390: 1940.
    2. Ezeh A, Oyebode O, Satterthwaite D, et al. The history, geography, and sociology of slums and the health problems of people who live in slums. Lancet. 2017; 389: 547-58.
    3. Lilford RJ, Oyebode O, Satterthwaite D, et al. Improving the Health and Welfare of People Living in Slums. Lancet .2017; 389: 559-70.
    4. Ezeh A, Sewankambo N, Plot P. Why the Path to Longer and Healthier Lives for all Africans is in Reach. The Conversation. 13 September 2017.
    5. Berman P. Catherine Kyobutungi: leading African health research capacity. Lancet. 2017; 390: 1942.


Measuring the Quality of Health Care in Low-Income Settings

Measuring the quality of health care in High-Income Countries (HIC) is deceptively difficult, as shown by work carried out by many research groups, including CLAHRC WM.[1-5] However, a large amount of information is collected routinely by health care facilities in HICs. This data includes outcome data, such as Standardised Mortality Rates (SMRs), death rates from ’causes amenable to health care’, readmission rates, morbidity rates (such as pressure damage), and patient satisfaction, along with process data, such as waiting times, prescribing errors, and antibiotic use. There is controversy over many of these endpoints, and some are much better barometers of safety than others. While incident reporting systems provide a very poor basis for epidemiological studies (that is not their purpose), case-note review provides arguably the best and most widely used method for formal study of care quality – at least in hospitals.[3] [6] [7] Measuring safety in primary care is inhibited by the less comprehensive case-notes found in primary care settings as compared to hospital case-notes. Nevertheless, increasing amounts of process information is now available from general practices, particularly in countries (such as the UK) that collect this information routinely in electronic systems. It is possible, for example, to measure rates of statin prescriptions for people with high cardiovascular risk, and anticoagulants for people with ventricular fibrillation, as our CLAHRC has shown.[8] [9] HICs also conduct frequent audits of specific aspects of care – essentially by asking clinicians to fill in detailed pro formas for patients in various categories. For instance, National Audits in the UK have been carried out into all patients experiencing a myocardial infarction.[10] Direct observation of care has been used most often to understand barriers and facilitators to good practice, rather than to measure quality / safety in a quantitative way. However, routine data collection systems provide a measure of patient satisfaction with care – in the UK people who were admitted to hospital are surveyed on a regular basis [11] and general practices are required to arrange for anonymous patient feedback every year.[12] Mystery shoppers (simulated patients) have also been used from time to time, albeit not as a comparative epidemiological tool.[13]

This picture is very different in Low- and Middle-Income Countries (LMIC) and, again, it is yet more difficult to assess quality of out of hospital care than of hospital care.[14] Even in hospitals routine mortality data may not be available, let alone process data. An exception is the network of paediatric centres established in Kenya by Prof Michael English.[15] Occasionally large scale bespoke studies are carried out in LMICs – for example, a recent study in which CLAHRC WM participated, measured 30 day post-operative mortality rates in over 60 hospitals across low-, middle- and high-income countries.[16]

The quality and outcomes of care in community settings in LMICs is a woefully understudied area. We are attempting to correct this ‘dearth’ of information in a study in nine slums spread across four African and Asian countries. One of the largest obstacles to such a study is the very fragmented nature of health care provision in community settings in LMICs – a finding confirmed by a recent Lancet commission.[17] There are no routine data collection systems, and even deaths are not registered routinely. Where to start?

In this blog post I lay out a framework for measurement of quality from largely isolated providers, many of whom are unregulated, in a system where there is no routine system of data and no archive of case-notes. In such a constrained situation I can think of three (non-exclusive) types of study:

  1. Direct observation of the facilities where care is provided without actually observing care or its effects. Such observation is limited to some of the basic building blocks of a health care system – what services are present (e.g. number of pharmacies per 1,000 population) and availability (how often the pharmacy is open; how often a doctor / nurse / medical officer is available for consultation in a clinic). Such a ‘mapping’ exercise does not capture all care provided – e.g. it will miss hospital care and municipal / hospital-based outreach care, such as vaccination provided by Community Health Workers. It will also miss any IT based care using apps or online consultations.
  2. Direct observation of the care process by external observers. Researchers can observe care from close up, for example during consultations. Such observations can cover the humanity of care (which could be scored) and/or technical quality (which again could be scored against explicit standards and/or in a holistic (implicit) basis).[6] [7] An explicit standard would have to be based mainly on ‘if-then’ rules – e.g. if a patient complained of weight loss, excessive thirst, or recurrent boils, did the clinicians test their urine for sugar; if the patient complained of persistent productive cough and night sweats was a test for TB arranged? Implicit standards suffer from low reliability (high inter-observer variation).[18] Moreover, community providers in LMICs are arguably likely to be resistant to what they might perceive as an intrusive or even threatening form of observation. Those who permitted such scrutiny are unlikely to constitute a random sample. More vicarious observations – say of the length of consultations – would have some value, but might still be seen as intrusive. Provided some providers would permit direct observation, their results may represent an ‘upper bound’ on performance.
  3. Quality as assessed through the eyes of the patient / members of the public. Given the limitations of independent observation, the lack of anamnestic records of clinical encounters in the form of case-notes, absence of routine data, and likely limitations on access by independent direct observers, most information may need to be collected from patients themselves, or as we discuss, people masquerading as patients (simulated patients / mystery shoppers). The following types of data collection methods can be considered:
    1. Questions directed at members of the public regarding preventive services. So, households could be asked about vaccinations, surveillance (say for malnutrition), and their knowledge of screening services offered on a routine basis. This is likely to provide a fairly accurate measure of the quality of preventive services (provided the sampling strategy was carefully designed to yield a representative sample). This method could also provide information on advice and care provided through IT resources. This is a situation where some anamnestic data collection would be possible (with the permission of the respondent) since it would be possible to scroll back through the electronic ‘record’.
    2. Opinion surveys / debriefing following consultations. This method offers a viable alternative to observation of consultations and would be less expensive (though still not inexpensive). Information on the kindness / humanity of services could be easily obtained and quantified, along with ease of access to ambulatory and emergency care.[19] Measuring clinical quality would again rely on observations against a gold standard,[20] but given the large number of possible clinical scenarios standardising quality assessment would be tricky. However, a coarse-grained assessment would be possible and, given the low quality levels reported anecdotally, failure to achieve a high degree of standardisation might not vitiate collection of important information. Such a method might provide insights into the relative merits and demerits of traditional vs. modern health care, private vs. public, etc., provided that these differences were large.
    3. Simulated patients offering standardised clinical scenarios. This is arguably the optimal method of technical quality assessment in settings where case-notes are perfunctory or not available. Again, consultations could be scored for humanity of care and clinical/ technical competence, and again explicit and/or implicit standards could be used. However, we do not believe it would be ethical to use this method without obtaining assent from providers. There are some examples of successful use of the methods in LMICs.[21] [22] However, if my premise is accepted that providers must assent to use of simulated patients, then it is necessary to first establish trust between providers and academic teams, and this takes time. Again, there is a high probability that only the better providers will provide assent, in which case observations would likely represent ‘upper bounds’ on quality.

In conclusion, I think that the basic tools of quality assessment, in the current situation where direct observation and/or simulated patients are not acceptable, is a combination of:

  1. Direct observation of facilities that exist, along with ease of access to them, and
  2. Debriefing of people who have recently used the health facilities, or who might have received preventive services that are not based in these facilities.

We do not think that the above mentioned shortcomings of these methods is a reason to eschew assessment of service quality in community settings (such as slums) in LMICs – after all, one of the most powerful levers to improvement is quantitative evidence of current care quality.[23] [24] The perfect should not be the enemy of the good. Moreover, if the anecdotes I have heard regarding care quality (providers who hand out only three types of pill – red, yellow and blue; doctors and nurses who do not turn up for work; prescription of antibiotics for clearly non-infectious conditions) are even partly true, then these methods would be more than sufficient to document standards and compare them across types of provider and different settings.

— Richard Lilford, CLAHRC WM Director


  1. Brown C, Hofer T, Johal A, Thomson R, Nicholl J, Franklin BD, Lilford RJ. An epistemology of patient safety research: a framework for study design and interpretation. Part 1. Conceptualising and developing interventions. Qual Saf Health Care. 2008; 17(3): 158-62.
  2. Brown C, Hofer T, Johal A, Thomson R, Nicholl J, Franklin BD, Lilford RJ. An epistemology of patient safety research: a framework for study design and interpretation. Part 2. Study design. Qual Saf Health Care. 2008; 17(3): 163-9.
  3. Brown C, Hofer T, Johal A, Thomson R, Nicholl J, Franklin BD, Lilford RJ. An epistemology of patient safety research: a framework for study design and interpretation. Part 3. End points and measurement. Qual Saf Health Care. 2008; 17(3): 170-7.
  4. Brown C, Hofer T, Johal A, Thomson R, Nicholl J, Franklin BD, Lilford RJ. An epistemology of patient safety research: a framework for study design and interpretation. Part 4. One size does not fit all. Qual Saf Health Care. 2008; 17(3): 178-81.
  5. Brown C, Lilford R. Evaluating service delivery interventions to enhance patient safety. BMJ. 2008; 337: a2764.
  6. Benning A, Ghaleb M, Suokas A, Dixon-Woods M, Dawson J, Barber N, et al. Large scale organisational intervention to improve patient safety in four UK hospitals: mixed method evaluation. BMJ. 2011; 342: d195.
  7. Benning A, Dixon-Woods M, Nwulu U, Ghaleb M, Dawson J, Barber N, et al. Multiple component patient safety intervention in English hospitals: controlled evaluation of second phase. BMJ. 2011; 342: d199.
  8. Finnikin S, Ryan R, Marshall T. Cohort study investigating the relationship between cholesterol, cardiovascular risk score and the prescribing of statins in UK primary care: study protocol. BMJ Open. 2016; 6(11): e013120.
  9. Adderley N, Ryan R, Marshall T. The role of contraindications in prescribing anticoagulants to patients with atrial fibrillation: a cross-sectional analysis of primary care data in the UK. Br J Gen Pract. 2017. [ePub].
  10. Herrett E, Smeeth L, Walker L, Weston C, on behalf of the MINAP Academic Group. The Myocardial Ischaemia National Audit Project (MINAP). Heart. 2010; 96: 1264-7.
  11. Care Quality Commission. Adult inpatient survey 2016. Newcastle-upon-Tyne, UK: Care Quality Commission, 2017.
  12. Ipsos MORI. GP Patient Survey. National Report. July 2017 Publication. London: NHS England, 2017.
  13. Grant C, Nicholas R, Moore L, Sailsbury C. An observational study comparing quality of care in walk-in centres with general practice and NHS Direct using standardised patients. BMJ. 2002; 324: 1556.
  14. Nolte E & McKee M. Measuring and evaluating performance. In: Smith RD & Hanson K (eds). Health Systems in Low- and Middle-Income Countries: An economic and policy perspective. Oxford: Oxford University Press; 2011.
  15. Tuti T, Bitok M, Malla L, Paton C, Muinga N, Gathara D, et al. Improving documentation of clinical care within a clinical information network: an essential initial step in efforts to understand and improve care in Kenyan hospitals. BMJ Global Health. 2016; 1(1): e000028.
  16. Global Surg Collaborative. Mortality of emergency abdominal surgery in high-, middle- and low-income countries. Br J Surg. 2016; 103(8): 971-88.
  17. McPake B, Hanson K. Managing the public-private mix to achieve universal health coverage. Lancet. 2016; 388: 622-30.
  18. Lilford R, Edwards A, Girling A, Hofer T, Di Tanna GL, Petty J, Nicholl J. Inter-rater reliability of case-note audit: a systematic review. J Health Serv Res Policy. 2007; 12(3): 173-80.
  19. Schoen C, Osborn R, Huynh PT, Doty M, Davis K, Zapert K, Peugh J. Primary Care and Health System Performance: Adults’ Experiences in Five Countries. Health Aff. 2004.
  20. Kruk ME & Freedman LP. Assessing health system performance in developing countries: A review of the literature. Health Policy. 2008; 85: 263-76.
  21. Smith F. Private local pharmacies in low- and middle-income countries: a review of interventions to enhance their role in public health. Trop Med Int Health. 2009; 14(3): 362-72.
  22. Satyanarayana S, Kwan A, Daniels B, Subbaramn R, McDowell A, Bergkvist S, et al. Use of standardised patients to assess antibiotic dispensing for tuberculosis by pharmacies in urban India: a cross-sectional study. Lancet Infect Dis. 2016; 16(11): 1261-8.
  23. Kudzma E C. Florence Nightingale and healthcare reform. Nurs Sci Q. 2006; 19(1): 61-4.
  24. Donabedian A. The end results of health care: Ernest Codman’s contribution to quality assessment and beyond. Milbank Q. 1989; 67(2): 233-56.

Worm Wars Continued

We have discussed results of deworming before and argued that it is important to treat at cluster level because of rapid re-infection from reservoirs in soil. A recent important meta-analysis compares deworming targeted at children versus a community-wide intervention.[1] It finds that community-wide approaches are more effective than treatment targeted at children for roundworms (Ascaris) and hookworms (Ancylostoma), but not whipworms (Trichuris). This finding is consistent with the much greater efficiency of the medicine in the former two worm types. The relative effect was greater in roundworms (odds ratio >16) than the more dangerous hookworms (OR >4), consistent with the shorter life-span of hookworm eggs than of roundworm eggs. These are important findings, but there is a worry that resistance may emerge with mass treatment. It would be interesting to see whether any studies have been done in slum populations specifically.

— Richard Lilford, CLAHRC WM Director


  1. Clarke NE, Clements ACA, Doi SA, et al. Differential effect of mass deworming and targeted deworming for soil-transmitted helminth control in children: a systematic review and meta-analysis. Lancet. 2017; 389: 287-97.

Let the Second Sanitary Revolution Begin

Despite the gains in recent years, far too many children still die before their fifth birthday. Childhood mortality in low income countries is 76 per thousand live births compared with 7 per thousand in high income countries.[1] Now that pneumococcal vaccine is in a widespread use we may expect diarrhoea to take over from pneumonia as the number one killer of children. Certainly in slums – soon to be home to over 1 billion people – diarrhoea is the greatest threat not just to life, but also to child health. Diarrhoea predisposes to chronic enteropathy, especially in malnourished children, which in turn predisposes to stunting and perhaps reduced cognitive development.[2]

But it does not have to be this way. The first ‘sanitary revolution’ in the second half of the 19th century in Europe and North America yielded massive gains in child survival.[3] Less than 4% of all development assistance has been allocated to urban water and sanitation improvement over the last few decades, according to Prof David Satterthwaite. Moreover, it is not as though Europe and America were awash with money; the per capita GDP of Britain in the 1860s ($703.1)[4] was roughly equivalent to that of Rwanda today ($697.3).[5] This suggests that a lack of political will is also to blame for poor sewage and water installations in modern day slums. And the pitiful state of sanitation in modern slums has been thoroughly documented.[6] Hardly surprisingly, improving sanitation is the number one priority for people who live in slums.[7] Water and sanitation is not a middle-class concern foisted on slum dwellers; it is a critically important issue that results in millions of child deaths and that local people want tackled.

There are of course barriers to tackling this problem relating to relative powerlessness of people in slums, poor local governance, immature financial markets, and so on. But there is another problem that is created entirely by a certain type of armchair academic – this is the pernicious idea that nothing can be done pending improvements in local and national governance. Such people argue that it is first necessary to improve security of tenure, functioning financial markets, and so on. An extension of this argument, for which empirical support is absent, is that water and sanitation is not enough; it must be part of an improvement in the whole slum ‘nexus’ to include solid waste disposal, street drainage, home improvement, etc. We cannot wait for extractive elites to disappear, the judiciary to be made independent, or every slum holder to achieve title before acting; Paris famously installed a functioning sewage system during the dictatorship of Napoleon the third following his coup d’état. Fortunately water and sanitation was prioritised at a recent WHO Technical Working Group on “Addressing Urban Health Equity Through Slum Upgrading” attended by the CLAHRC WM Director.

So, let the water and sanitation revolution begin. Let it be driven by political and social zeal but do not let it be undisciplined, and let us never forget that water and sanitation is a socio-technical innovation – it needs to be supported (ideally initiated) by local people themselves. Ensuring proper use and maintenance of sanitary facilities requires alignment of supply and demand.

A number of international organisation promote water and sanitation in low- and middle-income countries, for example the UN-HABITATs Water and Sanitation Trust Fund. But good intentions are not enough when it comes to sanitation – even where sanitation and water have been improved, the benefits on health are often nugatory.[8] [9] This is because the installations are inadequate, and/or because facilities are underused or poorly maintained. It is thus crucially important that interventions meet local needs, that they can be maintained, and that their effects in reducing exposure to infection and improving health are evaluated. Installation of improved water and sanitation utilities needs to be accompanied by research into how to make this socio-technical intervention work well and also summative evaluation of the effects on health and well-being.

— Richard Lilford, CLAHRC WM Director


  1. World Health Organization. Under-five mortality. WHO, 2016.
  2. Grantham-McGregor S, Cheung YB, Cueto S, Glewwe P, Richter L, Strupp B. Developmental potential in the first 5 years for children in developing countries. Lancet 2007; 369: 60–70.
  3. Szreter S. The Population Health Approach in Historical Perspective. Am J Public Health. 2003; 93(3): 421-31.
  4. Broadberry S, Campbell B, Klein A, Overton M, van Leeuwen B. British economic growth and the business cycle, 1700-1870. 2011. Working Paper.
  5. The World Bank. GDP per capita (current US$). 2016.
  6. Ezah A, Oyebode O, Satterthwaite D, et al. The history, geography, and sociology of slums and the health problems of people who live in slums. Lancet. 2016. [ePub].
  7. Parikh P, Parikh H, McRobie A. The role of infrastructure in improving human settlements. Urban Design Planning, 2012; 166; 101-18.
  8. Wolf J, Prüss-Ustün A, Cumming O, et al. Assessing the impact of drinking water and sanitation on diarrhoeal disease in low- and middle-income settings: systematic review and meta-regression. Trop Med Int Health. 2014; 19(8): 928-42.
  9. Fewtrell L, Kaufmann RB, Kay D, Enanoria W, Haller L, Colford JM, Jr. Water, sanitation, and hygiene interventions to reduce diarrhoea in less developed countries: a systematic review and meta-analysis. Lancet Infect Dis. 2005; 5(1): 42-52.

Systematic Review of Community Interventions – Essential Reading for All Applied Health Researchers – in Fact All Applied Researchers

Consider a non-governmental organisation (NGO) dedicated to improving welfare for those who live in African slums. How could the NGO proceed?

  1. Conduct a survey, find that sanitation is the most pressing problem across the majority of slums, and involve communities in the design and implementation of a system of latrines, pipes and treatment plants – a strategy shown to be effective in the literature.
  2. Consult with slum communities to find out their concerns and then co-design bespoke solutions according to local priorities – a sanitation system here; garbage removal system there; micro-finance elsewhere.
  3. Engage with local communities to increase their capacity and self-confidence. For example, by replicating the famous Detroit soup kitchen model.[1] Then let them be the architects of their own fate.

These are all very different, yet all go under the title “Community Interventions”. In a massive systematic review of controlled studies,[2] O’Mara-Eves et al. found that community interventions are effective compared to no community intervention, and many of the studies are of high quality. Hardly surprisingly, more sustained interventions are more effective than those of shorter duration. The take home message is that community activation is a good thing, notwithstanding a few situations where it may have an effect opposite to that intended.[3] As to which of the above three types is best, “no man knoweth it,” but one assumes that different modes suit different circumstances. For example, the CLAHRC WM Director would not recommend method three above, since slum residents generally do not have sufficient disposable wealth to be the architects of their own fate.

— Richard Lilford, CLAHRC WM Director


  1. Fenton-Smith R. Can Soup Change the World? BBC News. 13 March 2015.
  2. O’Mara-Eves A, Brunton G, McDaid D, et al. Community Engagement to Reduce Inequalities in Health: A Systematic Review, Meta-analysis and Economic Analysis. Public Health Research No. 1.4. Southampton, UK: NIHR Journals Library, 2013.
  3. Lilford RJ. Adverse Effects of Well-Intentioned Interventions to Improve Outcomes in Adolescence. CLAHRC WM News Blog. Jan 15 2016.

Poverty and Cognitive Function

It would appear that people who are chronically poor have lower cognitive functioning than the well-off.[1] Of course, which way round causality is working is not clear from this finding alone. However, even temporary poverty appears to affect cognitive reasoning, even if nutrition, time to complete the cognitive test, and work-effects do not vary. This latter study was based on Indian farmers tested at various points as their wealth changed across the seasons.[2] The authors postulate that the stress associated with poverty consumes mental resources that are not available for other concerns. These results provide a further argument for focussing resources on the poorest of the poor. For instance, people in registered slums in India have many amenities that are denied those in unregistered slums.[2] It would be better to spread meagre resources even more thinly in order to provide at least some help those who are poorly equipped to help themselves.+

— Richard Lilford, CLAHRC WM Director


  1. Mani A, Mullainathan S, Shafir E, Zhao J. Poverty Impedes Cognitive Function. Science. 2013; 341: 976-80.
  2. Subbaraman R, O’Brien J, Shitole, T, et al. Off the map: the health and social implications of being a non-notified slum in India 2012. Environ Urban. 2012; 24(2): 643-63.

Further Evidence from Informal Settlements

At last slum health, featured in previous blogs, is starting to receive the attention it deserves. A recent report on the Mathare settlement in Nairobi, Kenya [1] correlates how far a person lives from a public toilet and risk of disease. The further a person lives from the facility, the more likely they are to be chronically unwell, especially with diarrhoeal diseases and childhood stunting. As readers know, poor nutrition and sanitation create a vicious circle. Also, the risk of violence against women rises with distance from a public facility. Clean water and sanitation remain huge challenges for slum dwellers. Improved sanitation would also produce an educational and economic dividend. Meanwhile toilet design has improved, for example, with the invention of the composting toilet, so cost-effective, logistically feasible improvements are possible and likely to be highly cost-effective. The CLAHRC WM Director liked this paper because it integrated disease surveillance, geospatial mapping, and the personal accounts of slum dwellers, to create a rich account of pathways to poor health.

— Richard Lilford, CLAHRC WM Director


  1. Corburn J & Hildebrand C. Slum sanitation and the social determinants of women’s health in Nairobi, Kenya. J Env Public Health. 2015. [ePub]

Slums – Exploding Urban Myths!

The CLAHRC WM Director has recently returned from a two week attachment to the African Population Health Research Center (APHRC) in Nairobi. He stayed in the home of the Director, Dr Alex Ezeh, and his charming wife Nkee, to whom he extends his sincere thanks. APHRC is the foremost African centre for the study of slums*. The APHRC were among the first centres to question the idea (discussed in a previous post) that slums provide a frequent conduit from rural poverty to middle class urban life. In fact, for a large proportion of families, they are a sink; three generations can frequently be seen living in a single dwelling.

The APHRC have also exploded another myth – that while urban poverty appears more extreme than rural poverty to the casual observer, slum dwellers enjoy better health than their rural cousins. Research carried out by the APHRC showed that this was not the case for Kenya,[1] and this finding has since been replicated in Bangladesh.[2]

The Director visited the Viwandani slum in the company of APHRC staff with whom he is collaborating on a project on urban regeneration. Although a cursory inspection would suggest that one slum is much like another, deeper examination shows that this is not the case. Slum populations are more transitory in some places than others, suggesting that for some, slum life really is a step on the path to economic emancipation. There is a pronounced economic gradient within slums, with poverty increasing with distance from centres of employment. One thing that struck the Director was the need to pay for every item of service, including water and even access to the lavatory.

Despite the privations that people live under, and the malodorous crowded conditions outside, many slum dwellers maintain a remarkably high standard of personal hygiene, and the homes we were graciously invited to visit were absolutely spotless. The slum we visited had been exposed to a vigorous programme (in which APHRC is participating) promoting exclusive breast-feeding to the age of six months, and the babies we saw were sleek and healthy. One exception was a toddler with a crusty skin infection on his outer ear. The CLAHRC WM Director, pining after his days as a clinician, diagnosed impetigo and referred the child for urgent antibiotic treatment to reduce the risk of acute glomerulonephritis.

The health of slum dwellers has received much less attention than rural health – for example, there are upwards of 30 Health and Demographic Surveillance Sites (HDSS) in Africa, but until last year only one (managed by APHRC) in a slum area. You might ask what is different about slum vs. rural health – people in both areas are exposed to parasites, water-borne disease, and other afflictions of poverty. However, the spectrum of conditions differ and so do many of the solutions. Providing safe water and ensuring adequate garbage disposal are particular problems. So is the stress and danger of over-crowding, and the risk of fires and burns is high for many reasons. Slum health is mentioned in the Millennium Development Goal 7, but a recent Lancet editorial stated that this document “underestimated the magnitude of the problem by tenfold”.[3]

* Some people prefer the term “informal settlement”, perhaps because it is seen as less stigmatising or offensive to the people who live there. However, Africans speak of slums and this term is used in the research literature. Perhaps it is felt that a blander term would do more harm than good by ‘sanitising’ a harsh reality and reducing a sense of urgency?

— Richard Lilford, CLAHRC WM Director


  1. African Population and Health Research Center. Population and health dynamics in Nairobi’s informal settlements. Nairobi (Kenya): African Population Health Research Center. 2002.
  2. UNICEF. Understanding urban inequalities in Bangladesh: a prerequisite for achieving vision 2021. A study based on the 2009 multiple indicator cluster survey, 2010. [Online].
  3. The Lancet. Urban health post-2015. Lancet. 2015; 385: 745.

The Most Important Applied Research Paper This Year? Perhaps Any Year?

Walk through a poor rural or urban landscape and the vista seems to repeat itself unchanged. But delve deeper and differences appear. One robust finding from India is that poor Muslim children have a much better survival rate than poor Hindu children – childhood mortality is about one-fifth lower among Muslims. This finding is unaltered by adjusting for known confounders and, in any case, Muslim children in India are poorer and less educated than their Hindu peers. In development circles this is known as the “Muslim mortality paradox”. It was solved by Geruso and Spears in July this year [1] in a brilliant study based on the USAID Demographic Health Survey. Muslims are much less likely to defecate in the open than are Hindus. Hindus often regard defecation in the home as unclean and are more likely than Muslims to go outside to relieve themselves, even if the house is equipped with a functioning lavatory. The study shows a significant correlation between defecation in the open and mortality and confirms what has been thought by many politicians, right back to Mahatma Gandhi, who said “Sanitation is more important than independence”. I believe that we can draw a cause and effect inference from this data because:

  • It withstands adjustment for sex, mother’s education and wealth, and mother’s age at birth. In fact, controlling for education and wealth widens the gap in mortality between religions.
  • Muslims are no more likely to wash their hands, use soap or filter water than Hindus, and are less likely to have access to running water according to the data; again a bias against the hypothesis.
  • It has a good biological explanation. Chronic/recurrent infection/infestation causes stunting due to enteropathy [2] and perhaps a persistently altered microbiome.
  • The increased risk among Hindus who use a lavatory declines in proportion to the proportion of surrounding people who also use a lavatory.
  • Breastfed Hindu children experience much smaller increases in risk than non-breastfed Hindu peers – to me this was ‘the clincher’.

The effect of poor sanitation is so large, that it accounts for a greater quantum of mortality than the difference between the richest and poorest 20% of the population. The findings make the case for improved sanitation in all poor rural and urban areas of the world. In a previous blog I discussed failed approaches to improved health in slums – slum clearance just moves the problem elsewhere; land tenures creates slum-lords, etc. Behaviour change and other methods to improve sanitation could be the big breakthrough in improving lives of slum dwellers and rural poor people alike. CLAHRC Africa is already conducing a pilot study in West Africa, led by Dr Semira Manaseki-Holland, and we are aware of only three cluster intervention trials, all of which are use of solar-powered disinfection of drinking water.[3] [4] [5] However, the USAID Water, Sanitation and Hygiene (WASH) programme is co-ordinating further studies. We think that the step wedge design [6] is particularly suitable for evaluation in such interventions and they should include sound economic and educational end-points, along with health measures.

— Richard Lilford, CLAHRC WM Director


  1. Geruso M, & Spears D. Sanitation and health externalities: Resolving the Muslim mortality paradox. 2014. Working paper, University of Texas, Austin.
  2. Spears D, Ghosh A, Cumming O. Open Defecation and Childhood Stunting in India: An Ecological Analysis of New Data from 112 Districts. PLoS One. 2013. 8(9): e73784.
  3. du Preez M, McGuigan KG, Conroy RM. Solar Disinfection of Drinking Water In the Prevention of Dysentery in South African Children Aged under 5 Years: The Role of Participant Motivation. Environ Sci Technol. 2010; 44(2): 8744-9.
  4. du Preez M, Conroy RM, Ligondo S, et al. Randomized Intervention Study of Solar Disinfection of Drinking Water in the Prevention of Dysentery in Kenyan Children Aged under 5 Years. Environ Sci Technol. 2011; 45(21): 9315-23.
  5. McGuigan KG, Samaiyar P, du Preez M, Conroy RM. High Compliance Randomized Controlled Field Trial of Solar Disinfection of Drinking Water and Its Impact on Childhood Diarrhea in Rural Cambodia. Environ Sci Technol. 2011; 45(18): 7862-7.
  6. Hemming K, Lilford RJ, Girling AJ. Stepped-wedge cluster randomised controlled trials: a generic framework including parallel and multiple level designs. Stat Med. 2014