To the Editor In their Original Investigation in a recent issue of JAMA Internal Medicine, Pulakka et al1 examined the association between walking distance from home to the nearest tobacco outlet and smoking cessation and relapse. We noticed several limitations that should be considered.
First, Pulakka et al1 simply used the distance but did not consider the walkability2 of the neighborhoods, including the street connectivity, land use mix, and residential density. A neighborhood with higher street connectivity, for example, has higher accessibility to tobacco outlets than a neighborhood with lower street connectivity, providing that the walking distance from home to the tobacco outlet is the same between the 2 neighborhoods. Land use mix and residential density also contribute to the accessibility to the tobacco outlet. Therefore, measuring the distance from home to the tobacco outlet alone may not reflect the true accessibility. Second, assessment of smoking behavior in this study has also raised concerns that some nonregular smokers may have been misclassified as if they have quit smoking. Third, walking distance from home to the nearest tobacco outlet was the focus of this study, but the individuals’ functional capacity (eg, walking ability) and transportation preference (eg, whether the individuals walk or use other means of transportation within the neighborhood) were not addressed. For example, riding a bicycle for 1 km and walking for 1 km require different energy expenditure and may affect their motivation to go to the tobacco outlet. Fourth, the perceived distance to the nearest tobacco outlet should have been addressed, as the perceived environment may have stronger impact on behaviors than the actual environment.3
Lee KY, Lam MHS, Lee PH. Distance From Home to the Nearest Tobacco Outlet May Not Reflect the True Accessibility. JAMA Intern Med. 2017;177(2):287. doi:10.1001/jamainternmed.2016.8590