Realist theory construction for a mixed method multilevel study of neighbourhood context and postnatal depression

Eastwood et al. SpringerPlus (2016) 5:1081 DOI 10.1186/s40064-016-2729-9 Open Access RESEARCH Realist theory construction for a mixed method multilevel study of neighbourhood context and postnatal depression John G. Eastwood1,2,3,4,5,6*, Lynn A. Kemp4,7 and Bin B. Jalaludin2,4 Abstract Background: We have recently described a protocol for a study that aims to build a theory of neighbourhood context and postnatal depression. That protocol proposed a critical realist Explanatory Theory Building Method comprising of an: (1) emergent phase, (2) construction phase, and (3) confirmatory phase. A concurrent triangulated mixed method multilevel cross-sectional study design was described. The protocol also described in detail the Theory Construction Phase which will be presented here. Methods: The Theory Construction Phase will include: (1) defining stratified levels; (2) analytic resolution; (3) abductive reasoning; (4) comparative analysis (triangulation); (5) retroduction; (6) postulate and proposition development; (7) comparison and assessment of theories; and (8) conceptual frameworks and model development. Theory construction: The stratified levels of analysis in this study were predominantly social and psychological. The abductive analysis used the theoretical frames of: Stress Process; Social Isolation; Social Exclusion; Social Services; Social Capital, Acculturation Theory and Global-economic level mechanisms. Realist propositions are presented for each analysis of triangulated data. Inference to best explanation is used to assess and compare theories. A conceptual framework of maternal depression, stress and context is presented that includes examples of mechanisms at psychological, social, cultural and global-economic levels. Stress was identified as a necessary mechanism that has the tendency to cause several outcomes including depression, anxiety, and health harming behaviours. The conceptual framework subsequently included conditional mechanisms identified through the retroduction including the stressors of isolation and expectations and buffers of social support and trust. Conclusion: The meta-theory of critical realism is used here to generate and construct social epidemiological theory using stratified ontology and both abductive and retroductive analysis. The findings will be applied to the development of a middle range theory and subsequent programme theory for local perinatal child and family interventions. Background It is increasingly recognised that maternal and paternal depression has a significant impact on the developmental trajectory of infants and children both before and after birth. Much is now known about the genetic, biological, physiological and clinical influences on the genesis *Correspondence: ; 1 Community Paediatrics, Sydney Local Health District, Croydon Community Health Centre, 24 Liverpool Road, Croydon, NSW 2132, Australia Full list of author information is available at the end of the article of depression (Gluckman and Hanson 2006; Matthews and Meaney 2005; Meaney 2010; Osborne and Monk 2013; Monk et al. 2012; Meltzer-Brody 2011) and its subsequent impact on the unborn foetus, infants and other family members (Beck 1995; Murray et al. 1996; Martins and Gaffan 2000). We have previously reported on individual level psychosocial predictors of postnatal depression in South Western Sydney and proposed that “the findings were consistent with group-level socioeconomic deprivation, neighbourhood environment, social networks and ethnic diversity having causal effects on postnatal depressive © 2016 The Author(s). This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. Eastwood et al. SpringerPlus (2016) 5:1081 symptomatology and other perinatal outcomes” (Eastwood et al. 2011). We observed that the proposition was consistent with a recent qualitative study by O’Campo and colleagues “Neighbourhoods and mental well-being” (O’Campo et al. 2009) which found that “neighbourhood affordability, negative community factors including crime and vandalism, and social makeup including unemployment and poverty, were felt to be associated with poor mental wellbeing” (Eastwood et al. 2013). For the purposes of designing a theory driven population-based intervention programme we have undertaken to build a theory of maternal depression, the developmental origins of health and disease, and neighbourhood context. Drawing on recent criticism of social epidemiological studies and multi-level studies in particular (Muntaner 1999; Krieger 2001; O’Campo 2003; Carpiano and Daley 2006; Raphael 2006) we have used a realist explanatory theory building method (Eastwood et al. 2014). The purpose of this manuscript is to report on the findings of the Construction Phase of the main study (Eastwood 2011). Methods Introduction The Commonwealth of Australia has six States and two territories. Sydney is the capital city of the State of New South Wales (NSW) on the east coast. The study area is four local government city councils in South Western Sydney; has a diverse multicultural population with 28.4 % of the population born overseas compared with 17.8 % for the rest of NSW; and is an area of substantial social disadvantage, and have lower education attainment and lower income levels then other parts of NSW. Critical realism provided the methodological underpinning for this mixed method multilevel study. Critical realism assumes ontological and hierarchical stratification of reality (Danermark 2002) making it suitable for the examination of social and psychosocial phenomenon such as socio-economic stratification, social exclusion, isolation and cultural context. For critical realists, causation is not solely based on observed regularities in data (i.e., correlations or regression studies) but also on identifying the underlying causal mechanisms and how they work. We have previously reported on the protocol for the main study which used both Emergent and Construction Phases of a realist Explanatory Theory Building Method (Fig. 1) (Eastwood et al. 2014). The concurrent triangulation design used in this study is one of the most commonly used mixed method designs (Tashakkori and Teddlie 2003, p. 229). The research design used for this study sought to achieve the standards of integration proposed by Yin (2006) with integration occurring through use of common research questions, Page 2 of 26 Fig. 1 Phases of Explanatory Theory Building study design, units of analysis, samples for study and analytic strategies during both the Emergent and Construction phases. During the Emergent Phase a constant comparative approach between qualitative (inte (...truncated)