Michael V. Hayes

Using GIS-based methods of multicriteria analysis to construct socio-economic deprivation indices

BackgroundOver the past several decades researchers have produced substantial evidence of a social gradient in a variety of health outcomes, rising from systematic differences in income, education, employment conditions, and family dynamics within the population. Social gradients in health are measured using deprivation indices, which are typically constructed from aggregated socio-economic data taken from the national census – a technique which dates back at least until the early 1970s. The primary method of index construction over the last decade has been a Principal Component Analysis. Seldom are the indices constructed from survey-based data sources due to the inherent difficulty in validating the subjectivity of the response scores. We argue that this very subjectivity can uncover spatial distributions of local health outcomes. Moreover, indication of neighbourhood socio-economic status may go underrepresented when weighted without expert opinion. In this paper we propose the use of geographic information science (GIS) for constructing the index. We employ a GIS-based Order Weighted Average (OWA) Multicriteria Analysis (MCA) as a technique to validate deprivation indices that are constructed using more qualitative data sources. Both OWA and traditional MCA are well known and used methodologies in spatial analysis but have had little application in social epidemiology.ResultsA survey of British Columbias Medical Health Officers (MHOs) was used to populate the MCA-based index. Seven variables were selected and weighted based on the survey results. OWA variable weights assign both local and global weights to the index variables using a sliding scale, producing a range of variable scenarios. The local weights also provide leverage for controlling the level of uncertainty in the MHO response scores. This is distinct from traditional deprivation indices in that the weighting is simultaneously dictated by the original respondent scores and the value of the variables in the dataset.ConclusionOWA-based MCA is a sensitive instrument that permits incorporation of expert opinion in quantifying socio-economic gradients in health status. OWA applies both subjective and objective weights to the index variables, thus providing a more rational means of incorporating survey results into spatial analysis.

Neighbourhood quality and self-rated health : A survey of eight suburban neighbourhoods in the Vancouver Census Metropolitan Area

We investigated the relationship between perceptions of neighbourhood quality and self-rated health for residents of eight suburban neighbourhoods with modestly contrasting income profiles in the Vancouver Census Metropolitan Area. Survey respondents from lower income neighbourhoods more often rated their health as fair/poor, and perceived their neighbourhood to be of poor quality. The strongest predictors for fair/poor health status were employment status, body mass index, neighbourhood satisfaction, and age, while modest predictors were annual household income, neighbourhood median income profile, and perceptions of neighbourhood safety. The unique contribution of this study is its demonstration that social gradients in self-rated health are observable between neighbourhoods of even modestly contrasting income profiles.

Identifying social pathways for health inequalities. The role of housing.

To date, relatively little research has systematically investigated pathways between housing, socioeconomic status, and health status. 1 At the same time, there is a growing awareness that one of the most important research needs in health inequalities scholarship is to better elucidate those pathways by which differences in socioeconomic status manifest in everyday life, and produce, at the aggregate level, the systematic social gradient in health observed in all industrialized countries of the world. 2,3 Existing research on the influence of social support, workplace organization, relative and absolute income inequalities, and life-course influences on health give some preliminary direction as to the possible pathways at work in producing social gradients in health. In particular, power relations, identity, social status, and control over life circumstances emerge as factors differentially shaping the everyday lives of people at different points in the social hierarchy, with consequent effects on health status. 4 Three important dimensions of housing—its materiality, meaningfulness, and spatiality—are well known to shape power relations between social actors and groups, to influence the distribution of control over individuals’ life circumstances, and to differentially shape social identity and confer social status, 5 suggesting possible pathways between housing, social inequality, and population health. In this study, we sought to investigate links between social inequality, population health, and housing using a combination of quantitative and qualitative methods. Specifically, we conducted a mail survey of 522 residents of two lower-middle income Vancouver neighborhoods (Mount Pleasant and Sunset) and collected information on material and meaningful dimensions of people’s housing and neighborhood, as well as information on perceived neighborhood friendliness, social support, recent life events, work stress, self-rated health status, satisfaction with health, and mental health. T ABLE 1 shows the results of nonparametric tests for significant relationships between individual explanatory variables and individual outcome variables. Asterisks in the cells indicate a statistically significant relationship, and shading of the cell indicates the relationship was a graded one in the expected direction (see F IG . 1 for example of such gradients).

Randomised controlled trial of thermostatic mixer valves in reducing bath hot tap water temperature in families with young children in social housing

Objectives To assess the effectiveness of thermostatic mixing valves (TMVs) in reducing bath hot tap water temperature, assess acceptability of TMVs to families and impact on bath time safety practices. Design Pragmatic parallel arm randomised controlled trial. Setting A social housing organisation in Glasgow, Scotland, UK. Participants 124 families with at least one child under 5 years. Intervention A TMV fitted by a qualified plumber and educational leaflets before and at the time of TMV fitting. Main outcome measures Bath hot tap water temperature at 3-month and 12-month post-intervention or randomisation, acceptability, problems with TMVs and bath time safety practices. Results Intervention arm families had a significantly lower bath hot water temperature at 3-month and 12-month follow-up than families in the control arm (3 months: intervention arm median 45.0°C, control arm median 56.0°C, difference between medians, −11.0, 95% CI −14.3 to −7.7); 12 months: intervention arm median 46.0°C, control arm median 55.0°C, difference between medians −9.0, 95% CI −11.8 to −6.2) They were significantly more likely to be happy or very happy with their bath hot water temperature (RR 1.43, 95% CI 1.05 to 1.93), significantly less likely to report the temperature as being too hot (RR 0.33, 95% CI 0.16 to 0.68) and significantly less likely to report checking the temperature of every bath (RR 0.84, 95% CI 0.73 to 0.97). Seven (15%) intervention arm families reported problems with their TMV. Conclusions TMVs and accompanying educational leaflets are effective at reducing bath hot tap water temperatures in the short and longer term and are acceptable to families. Housing providers should consider fitting TMVs in their properties and legislators should consider mandating their use in refurbishments as well as in new builds.

Assessing the influence of the built environment on physical activity for utility and recreation in suburban metro Vancouver

BackgroundPhysical inactivity and associated co-morbidities such as obesity and cardiovascular disease are estimated to have large societal costs. There is increasing interest in examining the role of the built environment in shaping patterns of physical activity. However, few studies have: (1) simultaneously examined physical activity for leisure and utility; (2) selected study areas with a range of built environment characteristics; and (3) assessed the built environment using high-resolution land use data.MethodsData on individuals used for this study are from a survey of 1602 adults in selected sites across suburban Metro Vancouver. Four types of physical activity were assessed: walking to work/school, walking for errands, walking for leisure and moderate physical activity for exercise. The built environment was assessed by constructing one-kilometre road network buffers around each respondents postal code. Measures of the built environment include terciles of recreational and park land, residential land, institutional land, commercial land and land use mix.ResultsLogistic regression analyses showed that walking to work/school and moderate physical activity were not associated with any built environment measure. Living in areas with lower land use mix, lower commercial and lower recreational land increased the odds of low levels of walking for errands. Individuals living in the lower third of land use mix and institutional land were more likely to report low levels of walking for leisure.ConclusionsThese results suggest that walking for errands and leisure have a greater association with the built environment than other dimensions of physical activity.

Keeping children safe at home: protocol for three matched case–control studies of modifiable risk factors for falls

Background Childhood falls result in considerable morbidity, mortality and health service use. Despite this, little evidence exists on protective factors or effective falls prevention interventions in young children. Objectives To estimate ORs for three types of medically attended fall injuries in young children in relation to safety equipment, safety behaviours and hazard reduction and explore differential effects by child and family factors and injury severity. Design Three multicentre case–control studies in UK hospitals with validation of parental reported exposures using home observations. Cases are aged 0–4 years with a medically attended fall injury occurring at home, matched on age and sex with community controls. Children attending hospital for other types of injury will serve as unmatched hospital controls. Matched analyses will use conditional logistic regression to adjust for potential confounding variables. Unmatched analyses will use unconditional logistic regression, adjusted for age, sex, deprivation and distance from hospital in addition to other confounders. Each study requires 496 cases and 1984 controls to detect an OR of 0.7, with 80% power, 5% significance level, a correlation between cases and controls of 0.1 and a range of exposure prevalences. Main outcome measures Falls on stairs, on one level and from furniture. Discussion As the largest in the field to date, these case control studies will adjust for potential confounders, validate measures of exposure and investigate modifiable risk factors for specific falls injury mechanisms. Findings should enhance the evidence base for falls prevention for young children.

Investigating maternal risk factors as potential targets of intervention to reduce socioeconomic inequality in small for gestational age: a population-based study.

BackgroundThe major aim of this study was to investigate whether maternal risk factors associated with socioeconomic status and small for gestational age (SGA) might be viable targets of interventions to reduce differential risk of SGA by socioeconomic status (socioeconomic SGA inequality) in the metropolitan area of Vancouver, Canada.MethodsThis study included 59,039 live, singleton births in the Vancouver Census Metropolitan Area (Vancouver) from January 1, 2006 to September 17, 2009. To identify an indicator of socioeconomic SGA inequality, we used hierarchical logistic regression to model SGA by area-level variables from the Canadian census. We then modelled SGA by area-level average income plus established maternal risk factors for SGA and calculated population attributable SGA risk percentages (PAR%) for each variable. Associations of maternal risk factors for SGA with average income were investigated to identify those that might contribute to SGA inequality. Finally, we estimated crude reductions in the percentage and absolute differences in SGA risks between highest and lowest average income quintiles that would result if interventions on maternal risk factors successfully equalized them across income levels or eliminated them altogether.ResultsAverage income produced the most linear and statistically significant indicator of socioeconomic SGA inequality with 8.9% prevalence of SGA in the lowest income quintile compared to 5.6% in the highest. The adjusted PAR% of SGA for variables were: bottom four quintiles of height (51%), first birth (32%), bottom four quintiles of average income (14%), oligohydramnios (7%), underweight or hypertension, (6% each), smoking (3%) and placental disorder (1%). Shorter height, underweight and smoking during pregnancy had higher prevalence in lower income groups. Crude models assuming equalization of risk factors across income levels or elimination altogether indicated little potential change in relative socioeconomic SGA inequality and reduction in absolute SGA inequality for shorter height only.ConclusionsOur findings regarding maternal height may indicate trans-generational aetiology for socioeconomic SGA inequalities and/or that adult height influences social mobility. Conditions affecting foetal and childhood growth might be viable targets to reduce absolute socioeconomic SGA inequality in future generations, but more research is needed to determine whether such an approach is appropriate.

Examining the capacities of municipal governments to reduce health inequities: a survey of municipal actors' perceptions in Metro Vancouver.

OBJECTIVES: Canada is an increasingly urban nation, with considerable health inequities (HI) within its urban centres. While Canadian municipalities have a range of policy and planning levers that could reduce the burden of HI, little is known about how municipal employees perceive the capacities of municipal governments to address HI within their jurisdictions. This study sought to capture these perceptions through a survey of politicians and senior-level staff working in Metro Vancouver municipalities.METHODS: The survey was administered by mail to 637 politicians and senior-level staff from 17 municipal governments in Metro Vancouver. The survey captured respondents’ perceptions on the responsibilities of, opportunities for, and constraints on, municipal-level action to address HI, as well as respondents’ input on existing municipal policies and programs that could reduce HI in their jurisdictions.RESULTS: Respondents perceived senior governments to bear greater responsibility for reducing HI than municipalities. Investing in “parks &recreation facilities” was considered the most promising policy lever for addressing HI, while “insufficient federal and provincial funding” was perceived to be the greatest constraint on municipal action. “Affordable housing” and “recreational programs” were the most commonly identified existing strategies to address HI in the municipalities sampled.CONCLUSIONS: Our findings revealed concerns about inter-governmental downloading of responsibilities, and behaviour-based assumptions of disease etiology. To advance an urban health equity agenda, more work is needed to engage and educate municipal actors from a range of departments on the social determinants of health inequities.RésuméOBJECTIFS: Le Canada s’urbanise de plus en plus, ce qui crée d’importantes iniquités face à la santé (IFS) dans les centres urbains. Les municipalités canadiennes disposent de divers leviers stratégiques et de planification qui pourraient réduire le fardeau des IFS, mais on en sait peu sur la façon dont les employés municipaux perçoivent la capacité des administrations municipales de redresser les IFS sur leur territoire. Nous avons cherché à recueillir ces perceptions au moyen d’une enquête auprès des élus et des hauts fonctionnaires des municipalités du Grand Vancouver.MÉTHODE: L’enquête a été administrée par la poste à 637 élus et hauts fonctionnaires de 17 administrations municipales du district régional du Grand Vancouver. Les répondants ont été interrogés sur leurs perceptions des responsabilités, des possibilités et des contraintes de l’action municipale pour redresser les IFS, et nous leur avons demandé leur avis sur les politiques et les programmes existants susceptibles de réduire les IFS sur leur territoire.RÉSULTATS: Les répondants percevaient les paliers de gouvernement supérieurs comme ayant une responsabilité plus grande que celle des municipalités à l’égard de la réduction des IFS. L’investissement dans « les parcs et installations de loisir » était considéré comme le levier stratégique le plus prometteur pour redresser les IFS, tandis que « le financement fédéral et provincial insuffisant » était perçu comme le plus grand obstacle à l’action municipale. « Les logements à prix abordable » et « les programmes de loisirs » étaient les stratégies existantes les plus communément citées pour redresser les IFS dans les municipalités échantillonnées.CONCLUSIONS: Nos constatations font état de préoccupations sur le transfert des responsabilités entre les ordres de gouvernement et d’hypothèses comportementales sur l’étiologie des maladies. Pour promulguer un programme d’équité en santé en milieu urbain, il faut faire davantage d’efforts pour mobiliser et sensibiliser les acteurs municipaux, travaillant dans un éventail de services, à la question des déterminants sociaux des iniquités en santé.

The ecology of health services utilization in Grenada, West Indies

Few empirical investigations into the nature of health services utilization fully acknowledge that the home environment may act as a socio-geographic focus of both disease transmission and of learned health behavior. This paper examines the role of the home environment, as well as of personal characteristics and accessibility, in the utilization of health services in Grenada, West Indies. Bivariate and logit analyses of household survey data are employed to identify markers of high user individuals and households. Aspects of each domain of the home environment (physical and behavioral environment, demographics, and residential mobility) emerge as contributors to the utilization phenomenon in the study communities. Both etiological and socio-economic linkages are postulated to underlie the observed relationships. The implications of this work for health planning in developing countries is discussed.

The risk approach in diarrheal disease intervention in Grenada.

In a previous paper (Soc. Sci. Med. 23, 995-1002, 1986), we described the development of a method for identifying households at high risk of childhood diarrhea based on a logit analysis of data collected as part of a diarrhea disease control project in Grenada. In this paper, we report the results of a follow-up study designed to replicate the first using data on diarrhea incidence and risk factors collected in a different set of rural communities in Grenada. The findings of the first study were not replicated. There was no significant association between the risk factors and diarrhea in the follow-up study in contrast to the very strong associations found in the first study. As a consequence, it was not possible to construct a logit model from the second data set. The possible reasons for the contrasting sets of results and their implications for the application of the risk approach are discussed with reference to a two by two true-false table.