Dear Editor

We were interested to read the careful and detailed analysis of injury mortality data by Borrell et al.[1] We have also examined individual and neighbourhood effects on injury incidence in younger age groups and would like to draw these results to readers’ attention, as they extend and support the findings by Borrell et al. and were not referenced in their paper. In a study in Norwich, UK, we have shown that injury risk among preschool children is determined in part by individual and family factors such as sex, number of siblings, maternal age and lone parenthood, but in addition there were independent contextual neighbourhood effects which were partly accounted for by neighbourhood deprivation.[2] In a follow up study on injury risk to school-age children we have shown strikingly similar findings, both at the individual and neighbourhood level.[3] The neighbourhood effects again were only partly explained by deprivation, but the rest of the variation was not random because there was a high correlation between the neighbourhood risks in the preschool and school age groups. The type and mechanisms of injury are very different in these two age groups, with home based injuries predominating in the younger children and incidents at school, during sports activities or while unsupervised occurring in the older children. What this implies to us is that there are contextual (or collective[4]) neighbourhood factors influencing injury risk which operate at a deeper level than the immediate antecedents of an injury and probably reflect community based attitudes and behaviour around risk, safety, exposure and protection.

Like Borrell et al, we feel European studies are important as studies of this type are not necessarily generalisable across the Atlantic. The pattern of risk factors and meanings of neighbourhoods are different between countries, but probably there is a greater similarity within Europe. Also, as Borrell et al. imply, we are surprised there are not more studies of neighbourhood influences on injury risk, as the potential mechanisms are inherently more plausible than those which, presumably indirectly, influence cardiovascular health and all cause mortality.

References

(1) Borrell C, Rodriguez M, Ferrando J, Brugal MT, Pasarin MI, Martinez V,Plasencia A. Role of individual and contextual effects in injury mortality: new evidence from small area analysis. Injury Prev 2002;8:297-302

(2) Reading R, Langford IH, Haynes R, Lovett A. Accidents to preschool children: comparing family and neighbourhood risk factors. Social Science and Medicine 1999; 48:321-330.

(3) Haynes R, Reading R, Gale S. Household and neighbourhood risks for injury to 5-14 year old children. Social Science and Medicine 2003; in press.

(4) Macintyre, S., Ellaway, A. & Cummins, S. Place effects on health: how can we conceptualise, operationalise and measure them? Social Science and Medicine 2002;55: 125-139.