Table 1.

Variables used in the analyses

Type of variable	Original measurement	Used in the analysis	Other information
Outcome variable
Self-rated health (SRH)	Question “in general, how do you describe your overall health?” were on a 5-point scale: excellent/good/normal/bad/very bad	Grouped into three categories: excellent (excellent and good), normal, and poor (bad and very bad)
Individual-level variables
Socio-demographic
Age	Years
Marital Status	Four levels: Single, Married, divorced, widowed	Binary: never married (single) and ever married (including married, widowed and divorced)
Individual level socio-economic status
Education level	Illiterate	Categorised as: illiterate, <=9 years of education and >9 years of education	Nine years signifies compulsory basic education in Syria
	Total school years finished
Employment	Student or full-time house wife (economically inactive), employee (government or other) and employer (private business or self-employed professional)
Car ownership	Private ownership of a car was included as a binary variable, either yes or no
Item ownership	Binary (yes=1, no=0) for 6 items: a telephone, a mobile phone, a personal computer, an air conditioner, a television and a satellite dish	Numerical variable: summed responses to questions on the ownership of six items (yes=1, no=0) to create a numerical variable ranging from zero (no items) to six
Household crowding	Number of people living in the house	Divided the number of people living in the house by the number of rooms
	Number of rooms in the house
Health and Health behaviours
Body Mass Index (BMI)	Weight in kilograms divided by the square of the height in meters (kg/m2).
Level of physical activity	“Do you practice sport regularly?”
Smoking status	“Do you smoke cigarettes daily, occasionally or not at all”	Binary: currently smoking (daily or occasionally) or not currently smoking at all
Social support	“Do you have someone who supports you when needed?“ (yes, no)
	“Do you have someone to share happiness and sorrow with? (yes, no)
Perception of the neighbourhood
Annoyance of outdoor air pollution	“How much are you annoyed by outdoor air pollution if you keep the windows open?” (Not at all, somehow, much, very)
Annoyance of outdoor air pollution and noise	“How much are you annoyed by outdoor noise if you keep the windows open?” (Not at all, somehow, much, very)
Neighbourhood-level variables
Neighbourhood level SES
Percent illiterate			Individual level variables SES from the survey data were aggregated to the neighbourhood level
Percent unemployed
Average number of items owned
Percent with high density housing
Percent with no car
Formality Formal/Informal			These zones were non-overlapping with the formal zone occupying the west of Aleppo and the informal zone spreading out along the northern, eastern and southern borders of the formal zone. Formality was included as a binary fixed effect variable in the analysis with “formal” being the reference category