Theese are the basic components of a result chain, how actions can lead to a desired result. Construct an initial result chain based on a conceptual model than start analising the indicators of the process that lead to goals on a target.
Input ~ Strategy ~ Output ~ Outcome ~ Impact can be the chain.
Outputs, outcomes and impact are terms that are used to describe changes at different levels.
Output means the result of a trial, results which are achieved immediately after implementing an activity.
Outcome is not seen immediately after the end of the activity, after some time appear this kind of result, it seem to be better described as some change at the ground level after a training.
Impact is a long term result, not achievable during the project activities.
The external effectiveness is the indicator that shows the relationship between the product (output) and the result (outcome).
Look here for more external concept description.