Mental health is not simply the absence of mental illness but. You carry these questions into a psychological theory specifies the conceptual meaning of key terms and it identifies how variables are to be measured or operationalized. Provides a conceptual framework that links theoretical idea to concrete variables and their measurements are chosen. Intelligence, memory, anxiety etc. ( cannot be directly observed can be measured by collected data from multiple instruments, such as physiological recordings, behaviour rating scales) A construct has to be translated into a operational definition. An operational defn provides a recipe for specifying variables that are to be be used to measure a construct. An operational definition of construct is not limited to specifying hot to measure it (dependant variable) also spells out the conditions under which a construct is expected to occur (independent variable) Summary: the structure of scientific theory beings with constructs that are translated or operationalized into independent and dependant variables.