Table 1.

Definitions of symbols used in causal loop diagrams

Symbol	Definition
	A “ + ” sign denotes that an increase in variable “A” leads to an increase in variable “B”, or a decrease in variable “A” leads to a decrease in variable “B”, all things being equal. That is, variable “A” has a positive relationship with variable “B”
	A “ + ” sign denotes that an increase in variable “A” leads to a decrease in variable “B”, or a decrease in variable “A” leads to an increase in variable “B”, all things being equal. That is, variable “A” has a negative relationship with variable “B”
	The “R” denotes that the feedback loop is reinforcing, whereby an increase in “A” causes an increase in “B”, leading to a further increase in “A”. A decrease in “A” can also cause a decrease in “B” leading to further decrease in “A”. The feedback loop results in subsequent exponential change—either growth or decay
	The “B” denotes that the feedback loop is balancing, whereby an in “A” causes an increase in “B”, leading to a consequent decrease in “A”. Also, a decrease in “A” can cause a decrease in “B”, leading to a consequent increase in “A”. A balancing feedback loop will reach its limit over time and seeks an equilibrium
	“R1” denotes reinforcing loop 1, a unique identifier given to each reinforcing feedback loop identified. A short description of the feedback loop is included for ease of reference. A table summarising the feedback loops identified traces the causal pathway of each loop. This is done by following the order of the variables described in each feedback loop
	“B1” denotes balancing loop 1, a unique identifier given to each reinforcing feedback loop identified. A short description of the feedback loop is included for ease of reference. A table summarising the feedback loops identified traces the causal pathway of each loop. This is done by following the order of the variables described in each feedback loop