The vast majority of social programs and services have not yet been rigorously evaluated, and of those that have been rigorously evaluated, most (perhaps 75% or more), including those backed by expert opinion and less-rigorous studies, turn out to produce small or no effects, and, in some cases negative effects.

Even within areas where interventions do work, the differences in effectiveness are often significant. The Abdul Latif Jameel Poverty Action Labis a network of over 100 academics who carry out rigorous impact evaluations of interventions within international development.

Within a program area, they often find that the best interventions are more than ten times as effective as others with the same aim, even when excluding entirely ineffective programs.

To take one example, they studied interventions aiming to increase the attendance of teachers in the developing world. They found that half of the interventions studied had no effect whatsoever. Even once those were excluded, the best three were over ten times more effective than the worst intervention

Looking back on several decades of impact evaluations, we can see that good intentions and passion alone aren’t enough. Rather, we need a strategic approach that makes use of data where it is available, or seeks to gather data where it is not. It’s not that we should only focus on already proven interventions; rather, we should focus on implementing the best interventions we know given the evidence, or searching for new interventions that might be effective and testing them out.

Read the source article at 80000hours.org