Research 102

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Alert! Alert! 
Because NICHCY’s website will only remain online until September 30, 2014, most of its rich content has moved to a new home, the Center for Parent Information and Resources (CPIR), where it can be kept up to date. 

The new address of Research 102 at the CPIR is:


Updated August 2012

Wondering what all those research terms mean, and how much weight can you put on the conclusions the research authors draw? This Research 102 page takes a look at some basic research processes for adding up the evidence from individual studies and drawing bigger conclusions—about patterns and trends in what works and what doesn’t.

Table of Contents

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Research Reviews

The literature review.
“Lit reviews” abound in educational research. Most journal articles reporting research begin here, summing up our knowledge to date on the topic. So how do lit reviews differ from other types of summaries of research?

A literature review tutorial.

A Web tutorial on preparing scholarly reviews of the literature.

Basing decisions on the research: Does the new “way” work? Is it worth it?
Before changing teaching strategies, you want to have enough evidence that the new method will be an improvement. (p.s. Don’t be thrown by the screen you see when you click the link below. Simply register for free access.)

Research reviews and the problem of interpretive bias.
Even the results of one or two well-done studies aren’t enough to make you confident that it’s time for a change. Instead, you need to have a body of evidence to support that change. Usually, review articles are a good source of information. These are narrative articles describing an area of research on a particular question. However, authors may have an interpretation bias: Watch out for it.

Systematic reviews: Trying to avoid the bias by looking at the whole picture.
Systematic reviews attempt to avoid bias by covering all studies relevant to a given question, putting those results together, reporting strengths and weaknesses of those studies, and putting together a comprehensive summary.

Wikipedia’s explanation of systematic reviews.

What’s a systematic review, and how is it different from a literature review?

From the Annals of Internal Medicine.

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Meta-Analyses: The Next Step Up

A meta-analysis goes further than a systematic review. It’s a quantitative method that not only culls the results of many studies but also presents an estimate of the effect size. If you want to know more, these resources will help answer the question,”What is a meta-analysis?”

Meta-analysis, explained.

Wikipedia’s explanation of meta-analysis.

Wikipedia’s 1000 links to definitions of meta-analysis you’ll find on the web.
Need we say more, except maybe there aren’t a 1000 links…seems darn close, tho!

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What is Effect Size?

Wikipedia’s explanation.

Power analysis, statistical significance, and effect size.

And here’s a great primer on the subject.

Want to calculate an effect size yourself?  Try out this effect size calculator.

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Applications to Education

Okay, so how do you take research findings and apply them to educational questions or concerns?

Meta-analysis in educational research.

The push for usability.

Will it work for these students?

The case for validity generalization.

The generalizability of research results.

Did the study measure the right thing?

Operational definitions of concepts.

More on defining concepts.

Doing What Works.
The Doing What Works site is an offshoot of the What Works Clearinghouse, designed to take the findings of the WWC about specific educational research, translate them into usable materials and tools, and help educators get available research into practice.

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Would you like to visit another page in NICHCY’s series of Research Basics?

If so, use the links below to jump right there.

Research 101 | What makes for good research?

Research 102: Adding Up the Evidence | You’re here!

Making Sense of Statistics in Research | Don’t let stats throw you.

Weighing Info for Its Worth | Is this research well done?

Special Education Research: Where to Start? | How to begin finding and applying research.

What Works: Can We Say? | Where can I find information on evidence-based practices?

Research-Based Resources on Specific Disabilities |  A starting place for research-based information on disabilities.

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NOTICE: NICHCY is going away, but its resources are not. Find hundreds of legacy NICHCY publications, as well as our training curriculum on IDEA 2004, in the Center for Parent Information and Resources' Library at This website will remain available until September 30, 2014. After that date, web visitors will be automatically redirected to