Table 1.

Overview of informal settlement characteristics examples and the associated health conditions categorised by the four World Health Organization (WHO) dimensions of housing [19].

	Characteristic	Sub-Characteristic	Possible Outcome	Associated Health Condition	Sources
House	House size/space
		Crowding	Exposure to infection	Tuberculosis (TB)	[47]
			Socio-emotional vulnerability	Mental health	[45,48]
			Lack of living space	Injury, burns	[49]
	Structure
		Noise	Affects sleep and concentration	Mental health; irritability	[48,50]
		Damp/leaks	Mould	Respiratory illness e.g., asthma	[18,48,50]
		Ventilation	Exposure to infection	TB	[48,51]
	Inadequate onsite services	Waste	Pests (pesticides), pathogens	Bites, skin conditions	[48,52,53,54,55]
		Sources of energy	Indoor pollution	Exposure to carcinogens	[56]
			Illegal electricity connections	Injury, burns	[57,58]
Home	Living environment	Crowding	Socio-emotional vulnerability	Mental health	[45,48]
	Socioeconomic status
		Dissatisfaction/frustration	Mental wellbeing, substance abuse e.g., alcohol	Mental health e.g., depression, stress; violence	[44,59]
Neighbourhood	Environmental	Poor site location	Environmental risk e.g., flooding, exposure to heavy metals	Mental health; exposure to carcinogens	[18,43,48]
		Density of houses	Fires; exposure to infection	Burns, injury, infectious diseases	[18,47,48]
	Services	Access to facilities	Limited access to healthcare	HIV, TB, HIV/TB coinfection	[47]
	Inadequate infrastructure
		Lack of water	Storage of water	Infectious diseases	[60]
		Lack of sanitation	Use of other means, e.g., bush	Gender violence, crime	[59,61]
		Lack of drainage	Contaminated water	Infectious diseases	[42,62,63]
Community	Social networks	Social stressors	Gender inequality	HIV risk; interpersonal violence	[64,65,66]
			Frustration	Crime, substance abuse	[38,59,67,68]