A new study assessing four academic school years shows that California community college students in live classroom settings outperformed their online-course-taking peers in all measures, according to a University of California, Davis draft report.

Although the report -- Online Course-taking and Student Outcomes in California Community Colleges -- is still being finalized, its results are clear.

"Whichever way we look at it, we are finding consistently that students are performing better in the face-to-face sections versus the online sections," said co-author Cassandra Hart, assistant professor of education at UC Davis.

The robust evidence from student transcripts of poorer outcomes in online formats is true across groups of students, classes and professors, according to the report.

These results have implications for faculty and administrators whose awareness of the online performance penalty can result in new ways of promoting engagement and detecting disengagement among online students, according to the report.

"Students have to reach out a little more actively perhaps in an online setting," Hart explained, "It might be easier for instructors to just miss those cues. That's one possibility."

About a year ago, Hart came to the study out of her own interest and to add to the body of evidence surrounding student achievement in online environments, which is still small, she said.

Meanwhile, online course enrollments are growing. In California, online enrollments grew from constituting about half a percent of all classes in the 1995-96 academic year to more than 10 percent in 2011-12, according to the California Community Colleges Chancellor's Office.

Across the nation, online enrollment numbers increased by more than 8 million undergraduate enrollments from the 1997-98 to the 2006-07 academic years, to 9.8 million enrollments in online courses, according to the National Center for Education Statistics. Roughly half these enrollments, according to the report, were to community college courses.

Adding to the picture, policymakers have advocated for online courses, including California Gov. Jerry Brown who called for experimenting with expanding online course offerings as a way to decrease the high cost of higher education. 

Still, there is a lot to learn about the cost of online education, as well as how and why it affects student success, Hart said.

"As it becomes of interest to people to develop these courses, I think it also becomes of interest to evaluate how well students are doing in them compared to traditional formats," she said.

Although the study points to no clear explanation for this gap, it rules out others, like the effects of faculty characteristics -- such as teaching experience or tougher grading propensities -- on student online achievement. Students of professors teaching the same course online and face-to-face still fare worse online, according to the report.

Using the same fixed effects statistical modeling, the study also explored and ruled out biases in student characteristics or the possibility that more engaged or motivated students are prone to face-to-face instruction, and the chance that students are apt to select more challenging courses to take online.

"The raw comparison between online and face-to-face classes you might think would be biased because people who go into online versus face-to-face courses might look different from each other on a whole bunch of different dimensions," Hart said. "We tried to control for that."

Some ways the study accounted for bias was looking at student performance in the same course at the same college, looking at performance in the same course but across different sections and looking at the individual student across courses.

In the report, the authors note that greater self-motivation may be needed for online courses because they remove the structure of face-to-face meetings. The authors also, then, looked at students who take online courses outside of other structures -- like the calendar year -- to see whether they struggle more.

The resulting gap between online courses taken in the regular academic school year and those taken outside of it revealed an especially large performance gap in the latter group, seen most acutely during summer sessions.

Students also fared worse if enrolled in online courses where a smaller share of students -- 15 percent or less -- also enrolled in online sections versus face-to-face sections.

"These results," according to the report, "suggest that online students benefit from having a critical mass of peers taking the class in the same format."

Additionally, the study found a greater gap between online and face-to-face performance in math and humanities courses versus other types of courses.

On the flip side, the study found a smaller online performance gap for students who were successful academically in their first term, were transfer-oriented, or were taking a more-than-full-time course load. Asian students also had a smaller online versus face-to-face performance gap than other groups as well as male students, but only when assessing course failure and not completion rate outcomes, where female students did better.  

Although some studies have looked at slices of the question of student online success (for instance, online courses with partial face-to-face delivery), a couple of recent studies assessing the community colleges in Virginia and Washington and another assessing California's Community Colleges system also found that students in face-to-face courses stay in their classes longer and receive higher grades than their online-course-taking counterparts.

The UC Davis study found that students in online courses had "significantly lower" course completion rates, course passing rates, and rates of getting an A or B grade. What correlated most with poor performance, though, was course passing rates which the study assigned a 10-percentage-point performance decrease rate.

"Our study gives a valuable view on how online courses are performing now," Hart said, "One thing that's important to consider too is that they are still under development and still a relatively new technology."

She cautioned people from deciding from the study's results to halt online course offerings altogether, but also urged moderation for those wanting to build up too many online courses too fast without more evaluation.

"Continuing to develop the tools around these [online] courses is important and continued evaluation to see how they perform is going to be important as well," she said. 

The study's sample was taken from the 2008-09 through 2011-12 academic years that included more than 3 million student enrollments in nearly 60,000 courses, though the sample was whittled down to about 440,000 students to ensure they had like educational backgrounds and to account for other biases