A long road from a textbook to a degree
Graduation rate is the share of an entering group of students who finish a qualification within a stated time. It is the outcome that institutions, funders and families care about most, and also one of the hardest to link to any single policy. A materials policy, such as adopting open textbooks across a department, affects one small part of a student’s experience. A degree takes years, and a great deal happens in between.
This makes strong claims suspect. If a college reports that its graduation rate rose after introducing free materials, the honest first reaction is interest, followed by questions.
What a graduation rate measures
Definitions vary, and they matter. Common variations include:
- Time allowed. Finishing a four-year degree in four years is different from finishing within six. Part-time students may be counted differently or not at all.
- Who is in the group. Some measures cover only first-time, full-time students who start in the fall. Transfer students and part-timers can be left out, and they are a large part of many institutions.
- Where the student finishes. A student who transfers and graduates elsewhere may be counted as a non-completer at the first institution.
- Which qualification. Certificates, associate-level and bachelor-level programs differ.
Because rules differ between countries and sectors, graduation rates from different places are often not directly comparable.
How materials policy could plausibly connect
It helps to trace a possible chain, taking care to treat each link as uncertain.
- Materials are free, so fewer students delay or skip required readings.
- Students keep up better in early courses and are somewhat less likely to withdraw or fail.
- Fewer failed or withdrawn courses mean students stay on pace for credits.
- Staying on pace reduces extra terms and extra cost, which helps students persist.
- More students persist to the end.
Each step is reasonable, but each is also small, and a small effect at every step may shrink to very little by the end. For students who are close to the margin financially, textbook costs could matter more. For many others, the effect on whether they ultimately graduate is likely to be tiny.
Why the link is hard to prove
Time. Studying graduation means following cohorts for years. A policy introduced recently cannot yet show its effect on degree completion.
Many simultaneous influences. Tuition changes, advising programs, economic conditions, admissions standards and the mix of students all shift graduation rates. Separating out materials is difficult.
Dose. Open materials may be adopted in only a few courses. A student who meets free texts in two of forty courses has had a small exposure. Measuring this properly requires course-level records.
Selection. Departments that adopt open materials may already be strong on student support, so any association with better outcomes could reflect that.
A study that connects intermediate steps is more convincing than one that compares only start and end points. For example, evidence that students in open-text courses withdraw less is a step toward a graduation effect, though not proof of one.
Illustrative arithmetic
A hypothetical example helps show the scale problem. Suppose a college graduates 60 percent of an entering class of 1,000, which is 600 students. Suppose a policy improves persistence so that 6 more students graduate. That raises the rate from 60.0 percent to 60.6 percent (606 out of 1,000). Such a change would be real for those six people, but it would be very hard to distinguish from the ordinary year-to-year fluctuation in graduation rates. These figures are invented to show the point, not to predict an actual effect.
This does not mean the policy is not worth it. If it saves students money without harming learning, it can be justified on that ground alone. It does mean that a graduation-rate target may be an unfair test of a materials policy.
What to look at instead
If an institution wants to judge a materials policy, nearer-term measures are usually more informative:
- Share of students who have the required materials by the end of week one.
- Course withdrawal and failure rates in affected courses, compared with similar courses.
- Credits earned per term.
- Term-to-term persistence.
- Student reports on spending and on whether cost has changed their course choices.
These can be tracked from year to year and, together, offer a plausible picture of whether the policy is doing anything.
Other things that shape graduation
Graduation is influenced far more by factors such as financial aid, academic preparation, advising, work hours, family obligations and sense of belonging. Programs that combine several supports, such as structured advising, financial help and tutoring, are discussed more often than any single measure. Open materials can complement these, but are unlikely to replace them.
A cautious summary
The idea that free materials might help more students finish degrees is plausible but poorly tested at the level of graduation itself. Better evidence exists, in a limited form, for shorter-term outcomes. Anyone reading a claim of a large effect on graduation should look at the definition of graduation, how long students were followed, what else changed and whether the comparison was fair. For students, the practical point is simple: reducing costs of materials can ease a year’s budget, but finishing a degree depends on many things, and looking for help on all of them early is more useful than relying on any one.