One approach to screening is to observe whether there are physical, psychological, behavioral, or social indicators that suggest the misuse of drugs. For example, in the case of methamphetamine, one could look for characteristics such as:[1-4]
Physical Indicators
Psychological and Behavioral Indicators
Social Indicators
The reliability of simple observation is dependent in part on the experience and expertise of the observer as well as on the extent to which a client actually manifests various characteristics. Also, reliability can be limited by the possibility that indicators that may seem to be associated with drug misuse could be due to other factors. As such, while observation can be helpful, it is often best used in conjunction with additional screening procedures.