ESSER Funding and Research

 

 

The chart below identifies four different types of evidence—anecdotal, descriptive, correlational, causal—and highlights strengths and considerations of each evidence type.

 

Evidence TypeStrengthsConsiderations and Limitations

Anecdotal

May provide an indication of the context in which the intervention may be expected to be effective.

May identify aspects from user experience that may enhance or reduce effectiveness.

May help identify interventions that are promising enough to warrant more research.

Cannot provide strong support for claims based on subjective impressions.

Descriptive

May help identify interventions that are promising enough to warrant more rigorous research.

Does not include a comparison group so impossible to know what would have happened without the intervention.

Cannot alone provide strong support for claims about effect on outcome of interest.

Correlational

Useful starting point when learning about new interventions.

Cannot conclusively demonstrate that intervention gets results because it cannot rule out other possible explanations for differences in outcomes among users and non-users.

Causal

Determines effectiveness with confidence.

Ensures only difference between treatment group and comparison group is the intervention itself.

Not readily available for many educational products.