Related Experiment Video
Updated: May 9, 2026
10:26
Problem-Solving Before Instruction (PS-I): A Protocol for Assessment and Intervention in Students with Different Abilities
Published on: September 11, 2021
Evidence-based programs for schools: relationships between effect sizes and resource requirements
Joelle D Powers1, Aaron M Thompson
1School of Social Work, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA. jdpowers@email.unc.edu
Journal of Evidence-Based Social Work
|July 25, 2013
Summary
Schools often assume expensive, evidence-based programs yield better results. This study found the opposite: higher resource needs correlated with smaller effects in educational interventions.
Area of Science:
- Educational Psychology
- Program Evaluation
Background:
- Schools often seek evidence-based programs for improved student outcomes.
- A common assumption is that higher-cost interventions lead to greater effects.
Purpose of the Study:
- To investigate the relationship between resource requirements and effect sizes of evidence-based programs.
- To inform school practitioners' decisions regarding intervention selection.
Main Methods:
- Analysis of 51 evidence-based programs.
- Calculation of range and mean resource requirements for each program.
- Comparison of resource needs with program effect sizes.
Main Results:
- Contrary to intuition, programs with higher resource requirements exhibited smaller effect sizes.
- No positive correlation was found between program cost/resource needs and student outcome gains.
Conclusions:
- The intuitive link between higher resource investment and greater program effectiveness is not supported by empirical data.
- Practitioners should critically evaluate resource demands relative to expected outcomes when selecting interventions.
Related Concept Videos
02:20Correlations
Correlation means that there is a relationship between two or more variables (such as ice cream consumption and crime), but this relationship does not necessarily imply cause and effect. When two variables are correlated, it simply means that as one variable changes, so does the other. We can measure correlation by calculating a statistic known as a correlation coefficient. A correlation coefficient is a number from -1 to +1 that indicates the strength and direction of the relationship between...
01:22Dose-Response Relationship: Potency and Efficacy
The potency of a drug is the measure of its ability to produce a biological response and can be compared by looking at the half-maximum effective concentration or EC50 values of different drugs. A lower EC50 value indicates higher potency of the drug. In the dose–response curve of two antihypertensive drugs, candesartan and irbesartan, a significant difference is observed in their EC50 values. A lower EC50 value for candesartan indicates that it is more potent than irbesartan, as it produces...
01:52Regression Toward the Mean
Regression toward the mean (“RTM”) is a phenomenon in which extremely high or low values—for example, and individual’s blood pressure at a particular moment—appear closer to a group’s average upon remeasuring. Although this statistical peculiarity is the result of random error and chance, it has been problematic across various medical, scientific, financial and psychological applications. In particular, RTM, if not taken into account, can interfere when researchers try to extrapolate results...
02:55The Evidence for Evolution
Genetic variations accumulating within populations over generations give rise to biological evolution. Evolutionary changes can result in the formation of novel varieties and entire new species. These changes are responsible for the diverse forms of life inhabiting the planet. The evidence for evolution suggests that all living organisms descended from common ancestors.
01:12Hazard Ratio
The hazard ratio (HR) is a widely used measure in clinical trials to compare the risk of events, such as death or disease recurrence, between two groups over time. It reflects the ratio of hazard rates—the instantaneous risk of the event occurring—between a treatment group and a control group. This measure provides valuable insights into the relative effectiveness of a treatment by assessing how the risk of an event differs between the two groups.
For example, in a clinical trial evaluating a...
For example, in a clinical trial evaluating a...
01:13Psychology as a Science
Psychology, as a scientific discipline, aims to understand the mind and behavior through rigorous and systematic methods. The foundation of psychological research is evidence-based, relying heavily on the scientific method to derive and validate knowledge. This structured approach ensures that findings are reliable, valid, and applicable to broader contexts.
The scientific method in psychology involves six critical steps: making observations, formulating hypotheses, conducting tests, analyzing...
The scientific method in psychology involves six critical steps: making observations, formulating hypotheses, conducting tests, analyzing...