ask1 inhibitor br Methods br Results br Discussion

Methods
Results
Discussion The first objective of this study was to validate the three neighbourhood level variables of SES, built environment, and social capital. We defined social capital according to the social ask1 inhibitor perspective (Kawachi & Berkman, 2014) and constructed a composite scale based on the standard scale development methodologies (Streiner et al., 2014). First, in order to provide appropriate content validity (Harpham, 2008), the main aspects of social cohesion were measured by three direct questions. Our initial validation involved exploratory factor analysis and demonstrated that all items loaded onto a single underlying factor with relatively high loadings, which demonstrated a good factorial validity. The calculated Cronbach\'s alpha of 0.76 for the three-item scale demonstrated strong internal consistency (larger than 0.70) (Streiner et al., 2014) and being smaller than 0.90, was also an indication of no item redundancy (Boyle, 1991). We took one further step for the validation of the social capital measure by assessing its ecometric properties (Raudenbush, 2003) to show how much variations in the responses to social capital items are attributable to between-neighbourhood differences. The main purpose was to assess how appropriate this composite scale is as a neighbourhood-level measure and for measurement of neighbourhood attributes. The calculated ICC of 9% was relatively low and suggests that most of these variations are due to within-neighbourhood (individual) differences; however, there is no established standard to guide what constitutes a high ICC for ecometric analyses and very few studies were available for comparison. A study conducted in a sample from southern Brazil (Hofelmann, Diez-Roux, Antunes, & Peres, 2013) reported ICC measures ranging in value from 0.27 to 0.82 for various neighbourhood measurement scales such as perception of physical and social disorder. One explanation for our low ICC might be that we only had three items whereas in that study each scale included 8 items. Another existing study reported results that were also variable. Using data on neighbourhood conditions collected from a telephone survey of 5988 residents at three US study sites, Mujahid et al. (2007) employed a similar methodology for assessing the ecometric properties of seven different neighbourhood condition scales. They reported ICC measures in a range from 0.05 for the 5 items measuring ‘activities with neighbours’ to 0.51 for the 6 for measurement items of ‘aesthetic quality’. In concordance to other Canadian studies (Pampalon & Raymond, 2000; Vafaei et al., 2014), the two other neighbourhood-level variables of SES and built environment also showed high internal consistency, as demonstrated by Cronbach alpha measures of 0.77 and 0.80, as well as good psychometric properties. Conceptually, green space is not necessarily related to the other three street connectivity indicators, and one can argue against including all in a single scale; however, the relative high loading (0.56) of ‘green space’ onto a common factor supports our decision on constructing a single scale for built environment measures. To provide sufficient variations in the neighbourhood-level SES and built environmental factors that was needed for valid data analyses, we made use of data obtained from two Canadian cities that showed different ranges of such factors. To address the second objective we chose to study potential structural confounding effects of three neighbourhood-level factors of SES, built environment, and social capital. These factors have been shown to be potential risk factors for the occurrence of falls in older adults (Cole & Hernan, 2008; Gallagher & Scott, 1997; Syddall et al., 2012; Tinetti et al., 1995; West et al., 2004). Cross-tabular analyses suggested the presence of structural confounding, and social behavior appears that there is a social sorting mechanism in effect among this sample of community-dwelling Canadian older adults. Neighbourhoods with low levels of social capital also showed low levels of SES, suggestive of a clustering of multiple social disadvantages where economically poor communities also suffer from low levels of social capital. Polarisation and social division in large cities has been documented in various reports (Hulchanski, 2009; Simard, 2011) and we also showed the possibility of this issue in medium-sized Canadian cities.