Health literacy: check if the patient understood

A 62-year-old man leaves the office with three treatment changes, a request for a test and the instruction to come back in a month. At the door, the doctor asks if he has any questions. He smiles, says he understood everything and thanks her. Two weeks later, his daughter calls the clinic: her father stopped a medicine he should have continued, continued another he should have stopped and does not know what the test is for. Nobody lied. He thought he had understood, and she believed him.

This gap between what was said and what was understood is common, and almost always invisible to the person explaining. This text discusses what health literacy is, how many people have difficulty understanding and using health information, why professionals misjudge this difficulty and what research shows about teach-back, the technique of asking the person to explain in their own words what they are going to do.

Key points

• Health literacy is the ability to find, understand and use information to take care of one's own health, and it does not depend on schooling alone.
• About one in four people has inadequate or borderline health literacy, and this is associated with worse outcomes.
• Professionals tend to overestimate what the patient understood, and "any questions?" rarely reveals the problem.
• Teach-back asks the person to explain the plan in their own words and was effective in almost every study that evaluated it.
• Written instructions often require a reading level above what is recommended.
• Using plain language and checking everyone's understanding, without trying to guess who needs it, is the safest approach.

Summary

• What health literacy is
• How many people have difficulty
• Why doctors misjudge it
• What teach-back is
• What research shows about teach-back
• How to do teach-back in practice
• Written instructions and discharge
• Universal precautions and barriers
• Frequently asked questions
• Final checklist

What health literacy is

Health literacy is the set of skills that allows a person to find, understand, assess and use information to make decisions about their own health. It includes reading a prescription, understanding a schedule, interpreting a number on a test result, knowing when to come back and asking the professional questions. It is a practical skill that depends on context: someone may read a newspaper well and still get lost in front of a list of medicines with different schedules.

That is why health literacy is not the same as schooling. A study of patients admitted to the general medicine wards of 2 hospitals showed that people with low literacy and high schooling were more likely to return to the emergency department than the others (Shahid, 2022). The authors suggest that these people may go unnoticed precisely because the diploma makes the professional assume they understood (Shahid, 2022).

Literacy also changes with the situation. A person who is frightened, in pain, tired after a night in the emergency department or receiving difficult news understands less than they would on an ordinary day. The older adult who manages their own medicines well may get confused when the treatment changes all at once. Thinking of literacy as a fixed trait of the patient hides the fact that the consultation itself can make understanding easier or harder.

There is also numeracy, the ability to deal with numbers, proportions and risks. Understanding that a medicine is taken every eight hours, that a test value is above the target or that a risk has fallen by half requires a kind of reasoning that many people do not practice in daily life. When the explanation depends on numbers, the chance of misunderstanding grows.

It is worth remembering that low literacy rarely appears alone. It usually goes together with lower income, older age, several chronic diseases and less access to services. This does not mean that poor or older people do not understand, but that the burden of understanding and following a complex treatment weighs more on those already facing other difficulties. For primary care, the practical consequence is that clear communication is also a matter of equity: when the explanation is difficult, those who most need care are the ones who lose the most.

How many people have difficulty

A systematic review with 19 studies and 41,149 people with cardiovascular disease found inadequate or borderline literacy in about one in four (Fan, 2021). In the same review, lower literacy was associated with a higher risk of death (Fan, 2021).

In hospitalized patients, the proportion may be higher. In the study with internal medicine wards, half of the patients had adequate literacy, about one in three had inadequate literacy and about one in five was in the borderline range (Shahid, 2022). People with inadequate literacy had about three times the chance of returning to the emergency department within 90 days after discharge (Shahid, 2022).

Low literacy, however, did not worsen every outcome. In the same study, it was not associated with length of stay or readmission (Shahid, 2022). The return to the emergency department, though, is a sign consistent with the hypothesis that the person left without really knowing what to do at home and, faced with the first doubt, went to the only place they knew.

These numbers help size the problem, but they also show a limit: studies use different instruments, in different populations, and the proportion found varies. The practical point is that, in any primary care schedule, a relevant share of the people seen that day will have difficulty understanding and using what they heard, and the professional does not know in advance who they are.

Why doctors get the estimate wrong

Most professionals believe they can tell when the patient did not understand. The research suggests otherwise. A study with 287 patients compared the professionals' estimate of each person's literacy with the assessment made by the patients themselves and found frequent disagreement, with a tendency to overestimate (Voigt-Barbarowicz, 2022).

A review of 22 articles on professionals' perceptions added another problem: they understand health literacy in different ways and none of the studies reported using an instrument to measure it in routine practice (Louizou, 2024). Among the barriers cited for dealing with the topic was lack of time (Louizou, 2024).

The patient does not notice either. A review on communication at hospital discharge highlighted that most patients leave confused about the plan and do not recognize that confusion (Yen, 2019). The authors cite a classic memory study in which almost half of the information the patients remembered was incorrect (Yen, 2019).

Some reasons help explain why the estimation error is so common:

• the person nods and says they understood so as not to seem inattentive or ignorant;
• the shame of not reading well leads to disguise strategies, such as "I will read it at home calmly";
• the professional judges by appearance, speech or profession, and not by what the person can do;
• the question "any questions?" invites the answer "no" and ends the conversation;
• the patient remembers pieces of the guidance, but does not notice what was left out.

These mechanisms resemble the biases that affect diagnosis. The impression that someone "seems to understand" works as a shortcut, and shortcuts fail in predictable ways. The text on what to do with your own bias discusses how to recognize quick judgments about the patient.

The gap between the doctor's impression and what the person actually understood resembles a more general problem of clinical reasoning. The text on confidence and correctness as different measures shows that feeling sure and being right rarely go together, and the feeling that "I was clear" follows the same rule.

What teach-back is

If you cannot guess who understood, the way out is to check. Teach-back, sometimes called "teaching back", consists of asking the person to explain in their own words what they will do after the appointment. It is not a memory test nor an exam of the patient. It is a check of the professional's explanation: if the person cannot repeat the plan, the one who needs to explain it another way is the one who explained it.

The way the question is phrased makes a difference. Instead of "did you understand?", the professional can say something like "I want to be sure I explained it right; how are you going to tell your daughter what changed with the medicines?". The hospital discharge review recommends exactly this: asking the person to repeat the instructions in plain language and in a tone that does not embarrass them (Yen, 2019).

The cycle has four steps. First, the professional explains one point at a time, in plain language. Then they ask the person to say in their own words what they are going to do. If the answer shows a mistake or a gap, they explain again, another way. Finally, they check once more, until the person can state the essentials. In most consultations this takes a few minutes and focuses on what is riskiest to get wrong.

Teach-back does not need to cover everything that was said. It works best when the professional picks two or three points that really matter: what changed in the treatment, which signs require coming back sooner and when the next contact is. The rest can go in writing.

An example helps. After explaining that one of the medicines will be stopped and another will have its time changed, the doctor from the start of the text could say: "I changed quite a few things today and I want to be sure I was clear. Tell me what you are going to do with each medicine when you get home." If he says he will stop the wrong medicine, she finds the problem right there, with time to correct it, and not two weeks later through his daughter's phone call. The question costs less than a minute and changes what the consultation can guarantee.

What the research shows about teach-back

A systematic review on the implementation and impact of teach-back gathered 20 studies and found a positive effect in 19 of them, in outcomes such as understanding, self-care, adherence and readmission (Talevski, 2020). The authors noted that the way the technique was applied varied widely between studies, which makes it hard to know which version works best (Talevski, 2020).

Another review, on interventions to improve patient understanding in consent and health education, assessed 52 studies (Glaser, 2020). In the studies that tested teach-back or verbal check with return, understanding improved in 3 of 3 (Glaser, 2020).

A study with 3994 adults with ambulatory care sensitive conditions, such as diabetes and cardiovascular disease, analyzed what patients reported about the professional's communication (Hong, 2019). Those who reported that the professional usually asked them to explain back had a lower risk of hospitalization (RR 0.85) and of readmission (HR 0.77) (Hong, 2019). There was no difference in length of stay, and about one in three participants said they never received this kind of request (Hong, 2019).

The effect was clearer in people with cardiovascular disease and diabetes (Hong, 2019). It makes sense: these are conditions in which treatment changes often, depends on several medicines and requires the person to recognize signs of worsening at home.

These results have limits. Hong's study is observational, based on patient reports, and does not prove that teach-back caused the reduction. The reviews gather small and heterogeneous studies. Still, the direction is consistent, the technique is cheap and the risk of harm is practically nil, which makes it reasonable to adopt as routine.

The tone of the conversation weighs as much as the technique. When the patient feels welcomed, they admit more easily that they did not understand. The text on why empathy enters reasoning discusses how the relationship changes the quality of the information that circulates in the consultation.

How to do teach-back in practice

The technique seems simple, but it requires some choices. The table below sums up formulations that work and those that usually fail.

Situation	Question that fails	Question that checks
Change in treatment	"Did you understand how to take it?"	"Tell me how you are going to take the medicines starting tomorrow."
Warning signs	"Do you know when to come back?"	"If you get worse at home, what will you watch for and what will you do?"
Test ordered	"Any questions about the test?"	"What is this test for and where are you going to have it done?"
Follow-up	"Agreed?"	"When is the next appointment and what should you bring?"
Explanation for the family	"Was it clear?"	"How are you going to explain to your husband what we talked about?"

Some attitudes help the question work. The first is to take responsibility for the explanation, with phrases like "I want to see if I explained it well." The second is to ask about an action, not a concept: it is more useful to know what the person will do tomorrow morning than whether they know the name of the disease. The third is to accept the wrong answer naturally and explain again, in another way, without repeating the same words more loudly.

It is also worth doing teach-back in small steps, after each important block, and not only at the end. A long list explained all at once and checked at the last minute tends to fail. When the person comes with a companion, the companion can take part in the check, as long as the person agrees and remains at the center of the conversation.

The technique fits into shared decision making. Explaining options and checking whether they were understood is a condition for the person to choose for real. The text on shared decision making with the patient discusses how to present benefits and harms in a way that lets the person take part.

The same logic applies to difficult conversations. Explaining a mistake, a change of plan or bad news requires simple language and confirmation of understanding; the text on phrases that help and phrases that get in the way offers concrete examples.

Written instructions and discharge

Written guidance is often seen as the solution: if the person forgets, they read it later. The problem is that many texts are hard to read. An analysis of discharge instructions found an average reading level of about 9 years of schooling, above what is recommended for health material (Burns, 2022). Only 44 of the instructions analyzed were within the recommended level, and the reading level did not correlate with readmission (Burns, 2022).

The lack of correlation does not mean the text does not matter. It suggests that paper alone does not solve it: the person needs to understand the guidance at the time, with someone who can clear up doubts, and the text serves as a reminder of what was already understood. The review on hospital discharge reinforces this combination of oral explanation, simple written material and checking of understanding (Yen, 2019).

Some rules help write guidance the person can use:

• short sentences, with one idea per sentence;
• everyday words instead of technical terms, such as "high blood pressure" instead of the technical name;
• what to do first, and the reason after;
• times and concrete actions, such as "in the morning, after breakfast";
• warning signs set apart from the rest, highlighted;
• space for the person to write in their own words.

Drawings, schedule tables and the medicine packaging itself separated by time of day can help more than a well-written paragraph. The principle is the same as with teach-back: the material serves the person who will use it, not the professional who produced it.

The transition between services is an especially risky moment. At hospital discharge or after a specialist appointment, the person receives guidance from a professional they may not see again, and primary care inherits the plan without having taken part in it. A follow-up appointment shortly after discharge, with a simple check of what the person understood, can correct mismatches before they become a return to the emergency department.

Conversations about the future, such as decisions about the end of life, depend even more on real understanding. The text on why the planning conversation matters shows how to check what the person understood before recording their choices.

Universal precautions and barriers

If the professional cannot identify who has low literacy, one option is to treat everyone as if they might have difficulty. This approach, called universal literacy precautions, proposes simple language, few messages at a time and checking of understanding for all people, and not only for those who "seem to need it."

The advantage is avoiding embarrassment and selection error. No one feels labeled, and those who understand well lose little time. Those who have difficulty, on the other hand, receive the help they needed without having to ask. Since professionals tend to overestimate understanding (Voigt-Barbarowicz, 2022), informal screening leaves out precisely those who would need it most.

The behavior of professionals also depends on what they themselves know. A study with 50 physicians and 50 administrative staff showed that the literacy of the professionals themselves and their attitudes were associated with the use of communication techniques with patients (Mor-Anavy, 2021). In another study, with 522 diabetes educators, plain language, written material and teach-back were the most used techniques, and those who had received literacy training used more techniques (Howe, 2017).

These data suggest that teach-back is a skill that is learned and trained, like the physical examination. Without training, the tendency is to go back to "any questions?". With training, the check question becomes part of closing the consultation.

The whole team can take part. Reception, nursing, pharmacy and community health workers have contact with the person at different moments and can notice signs the physician does not see, such as difficulty filling out a form or doubt about a time. When each one checks understanding at their point of contact, the chance of the misunderstanding moving forward decreases. The text about what interprofessional clinical reasoning is discusses how different professionals contribute to care.

The most cited barrier is time. Professionals report that there is no room in the consultation to check understanding of each point (Louizou, 2024). In practice, well done teach-back tends to be short, because it focuses on the essentials. And the time spent now can avoid the phone call, the early return visit or the trip to the emergency department because of a misunderstanding.

Another barrier is the fear of seeming condescending. Asking an adult to repeat the explanation can sound like distrust. The way out lies in the wording: when the professional makes clear that they are checking their own explanation, and not the person's intelligence, the reaction tends to be good. Using the same approach with everyone also reduces the feeling of being tested.

There are also situations that require adaptation. When the person speaks another language, the check needs to go through the interpreter, and the text about how to conduct an interpreted consultation shows the care involved. People with hearing, visual or cognitive impairment may need more time, other formats and the participation of a caregiver.

Finally, there is habit. Physicians learn to explain, but rarely learn to check whether they were understood. Practicing with colleagues, recording consultations with consent or simply choosing one point per consultation to do teach-back are ways to start.

Frequently asked questions

Is health literacy the same as knowing how to read?

The concept is broader than knowing how to read. It includes understanding, evaluating and using information, including numbers and risks. People with high schooling and low literacy were more likely to return to the emergency department in a study with hospitalized patients (Shahid, 2022).

How many patients have difficulty?

It depends on the population and the instrument. A review with 41,149 people found inadequate or borderline literacy in about one in four (Fan, 2021).

Can you tell who did not understand?

Most of the time, no. Professionals' estimate of patients' literacy often disagrees with the patients' own assessment, with a tendency to overestimate (Voigt-Barbarowicz, 2022).

Does teach-back work?

A review found a positive effect in 19 of 20 studies (Talevski, 2020). In adults with chronic conditions, the report of teach-back was associated with lower risk of hospitalization and readmission (Hong, 2019).

Does teach-back not take too much time?

It tends to be short when it focuses on two or three essential points. Lack of time is a barrier cited by professionals (Louizou, 2024), but the check can avoid return visits and phone calls later.

Does giving the guidance in writing solve it?

It helps as a complement to the conversation. Discharge instructions often require a reading level above what is recommended (Burns, 2022). The text works better as a reminder of what has already been explained and checked.

Final checklist

• Use plain language and few messages at a time with everyone.
• Replace "any questions?" with a request to explain the plan in their own words.
• Take responsibility for the explanation when making the request.
• Focus the check on what changes in treatment, on warning signs and on follow-up.
• Explain it another way when the response shows a gap and check again.
• Provide simple written guidance as a reminder of what has already been understood.

References

1. Burns ST, Amobi N, Chen JV, et al. Readability of Patient Discharge Instructions. J Gen Intern Med. 2022. PMID 34240287. DOI 10.1007/s11606-021-06988-y.
2. Fan ZY, Yang Y, Zhang F. Association between health literacy and mortality: a systematic review and meta-analysis. Arch Public Health. 2021. PMID 34210353. DOI 10.1186/s13690-021-00648-7.
3. Glaser J, Nouri S, Fernandez A, et al. Interventions to Improve Patient Comprehension in Informed Consent for Medical and Surgical Procedures: An Updated Systematic Review. Med Decis Making. 2020. PMID 31948345. DOI 10.1177/0272989X19896348.
4. Hong YR, Cardel M, Suk R, et al. Teach-Back Experience and Hospitalization Risk Among Patients with Ambulatory Care Sensitive Conditions: a Matched Cohort Study. J Gen Intern Med. 2019. PMID 31385206. DOI 10.1007/s11606-019-05135-y.
5. Howe CJ, Walker D, Watts J. Use of Recommended Communication Techniques by Diabetes Educators. Health Lit Res Pract. 2017. PMID 31294260. DOI 10.3928/24748307-20170810-01.
6. Louizou E, Panagiotou N, Dafli E, et al. Medical Doctors Approaches and Understanding of Health Literacy: A Systematic Literature Review. Cureus. 2024. PMID 38298293. DOI 10.7759/cureus.51448.
7. Mor-Anavy S, Lev-Ari S, Levin-Zamir D. Health Literacy, Primary Care Health Care Providers, and Communication. Health Lit Res Pract. 2021. PMID 34260319. DOI 10.3928/24748307-20210529-01.
8. Shahid R, Shoker M, Chu LM, et al. Impact of low health literacy on patients' health outcomes: a multicenter cohort study. BMC Health Serv Res. 2022. PMID 36096793. DOI 10.1186/s12913-022-08527-9.
9. Talevski J, Wong Shee A, Rasmussen B, et al. Teach-back: A systematic review of implementation and impacts. PLoS One. 2020. PMID 32287296. DOI 10.1371/journal.pone.0231350.
10. Voigt-Barbarowicz M, Dietz G, Renken N, et al. Patients' Health Literacy in Rehabilitation: Comparison between the Estimation of Patients and Health Care Professionals. Int J Environ Res Public Health. 2022. PMID 35329219. DOI 10.3390/ijerph19063522.
11. Yen PH, Leasure AR. Use and Effectiveness of the Teach-Back Method in Patient Education and Health Outcomes. Fed Pract. 2019. PMID 31258322.