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Test yourself

Test whether you can recognise claims that have a bad basis, check the trustworthiness of evidence used to support claims, and make good health choices.

Question 1

A herbalist wanted to find out which herbs were best for treating people with headaches, so she did a research study to compare green herbs with yellow herbs. The people who used the green herbs had fewer headaches compared to the people who used the yellow herbs.

How sure can we be that green herbs are better than yellow herbs?

Question 2

Imagine you hear about a drink made from beetroot on the radio. The makers of the drink say that if you have some of it every day, you will live a long life.

Based on what the makers of the drink claim, how sure can you be that beetroot will give you a long life?

Question 3

Thomas says that eating healthy foods will keep him from getting sick. George says we cannot be certain about this, so Thomas should eat whatever he wants. Edith says that although we cannot be certain, eating healthy foods is probably a good idea.

Who is right?

Question 4

Molly has a tummy ache. She says she needs medicine to make her better.

Is she right?

Question 5

Imagine you read a story in the newspaper saying that using a cream on your skin can keep you from getting sick by improving how your blood moves. The story also says that the cream is harmless because it is made of natural oils.

Based on this, how sure can you be that the cream will keep you from getting sick?

Question 6

Peter often has a headache. A friend advises him to exercise. He says that people who exercise have fewer headaches than people who do not exercise. Based on this link between exercise and headaches, Peter’s friend says that exercise will give him fewer headaches.

Is Peter’s friend right?

Question 7

Alice hears a story on the radio about a large study with more than 1,000,000 people. The study used national data. It found that out of many different treatments, one was most effective. The reporter says you can be very sure about this because it was such a big study, using real world data.

Is the doctor right?

Question 8

Doctors studied people with stomach pain before and after they took a new medicine. After taking the new medicine, many people felt less pain.

Can we be sure that the new medicine is good for treating stomach pain?

Question 9

Harriet is worried about getting sick. She hears about a new research study on the radio that compared a new medicine to an old medicine. Fewer people who took the old medicine got sick compared to the people who took the new medicine.

How sure can Harriet be that the old medicine is better than the new medicine?

Question 10

Imagine you read a story in the newspaper about a herbal medicine for treating headaches. In the story, a doctor says that even though the medicine has been used for a long time and that many people say it has worked for them, we cannot be very sure that it is helpful.

The doctor is right, but why do you think he is?

Question 11

Imagine you have a fever and a new treatment for fever is available in the shops.

Is the new treatment much more likely to be better than older treatments?

Question 12

Wamala has a very bad cough and is preparing for his final exams. He starts by using a drink, a cough medicine, to get better. Instead of taking one drink, as he normally does, he takes two drinks. He thinks that this will help him get rid of his cough more quickly.

Is Wamala right that taking two drinks of cough medicine is better than taking one?

Question 13

David is scared about getting a serious illness, and wonders if he should have a test to make sure he does not have the illness. His doctor tells him that there is a treatment for this disease, but this treatment has the same effect whether the illness is detected early or late.

If a treatment has the same effect, no matter when people take it during the illness, then early detection of the illness will:

Question 14

Ruth says that you can be very sure about the effects of naturopathic (“natural") treatments because they are tailored to each individual patient.
With most medical treatments, you don’t know who will benefit and who will not, unless they are also tailored to individual patients.

Is Ruth right?

Question 15

Two companies make two different medicines for treating stomach pain. Each of them says that their medicine is the better one.

How can you know which of the two medicines is better for stomach pain?

Question 16

George has stomach pain. The last time George had a stomach pain was two months ago. That time, he drank some hot milk and after an hour, his stomach pain was gone. Therefore, George says hot milk cures stomach pain.

Is George right?

Question 17

Imagine your friend has a skin rash. He says that he will try a cream for it, which was recommended by an expert on the radio. Your friend says that “experts are always up to date with studies comparing treatments”.

Is your friend right to believe this?

Question 18

Eric sees a story about a new treatment for joint pain. The reporter had interviewed someone who said the new treatment is effective and safe. She said you can be sure about this because the study was published in a well-known, prestigious medical journal.

Do you agree?

Question 19

In a research study, doctors gave a new treatment - a medicine - to people with stomach pain, and an older medicine to similar people. The doctors decided who should get the old treatment and the new treatment.

How sure can we be about the results of this comparison of the two treatments?

Question 20

Richard hears a programme about treatments for headaches. Two new treatments are discussed - Ease and Relieve. Each was compared to paracetamol in randomised trials (fair comparisons), but not to each other.
Both were more effective than paracetamol, but Ease was much more effective than paracetamol.

How sure can Richard be that Ease is more effective than Relieve?

Question 21

A doctor did a research study to find out if a new medicine for people having problems with breathing was better than an older medicine. In the study, people were given either the new medicine or the older medicine. The doctor asked people who were given the new medicine to visit her during the following weeks. The people who got the old medicine just sent messages to the doctor about how they felt.

We cannot be sure about the results of this study. Why?

Question 22

Sharifa wants to get rid of her pimples. She finds a research study done by doctors comparing people washing their face with soap and people washing their face with only water. The doctors tried to hide from the people taking part in the study whether they were using soap or just water.

However, many people who used water figured out that they had not been given soap, and so stopped washing their faces. At the end of the study, more people had pimples in the group who got only water.

How sure can Sharifa be that soap gets rid of pimples?

Question 23

Alice has made a new drink to cure stomach pain. She decided to do a research study to compare people drinking her new drink with people drinking water. At the end of the study, she asked people how much stomach pain they had.

Why can’t we be sure about the results of this study?

Question 24

Eve wants to lose weight, but she has a hard time controlling what she eats.
She reads about a research study of a treatment developed by psychologists at a well-known university to help people control what they eat. The study measured people’s ability to control what they eat using a questionnaire that was completed at the end of the study. The questionnaire was developed by the psychologists.

How sure can Eve be that the results of the study?

Question 25

A doctor compared two treatments in a research study of people with back pain. However, the doctor was not able to stay in touch with many of the people who started the study.

How sure can we be about the results of this study?

Question 26

In a study, doctors compared two treatments for stomach pain, a new and an old treatment. They tossed a coin to decide who would get which treatment. Some people who took the new treatment felt ill and changed to the old treatment instead. At the end of the study, the doctors compared how much pain people experienced. The people who had changed from the new treatment to the old treatment were counted among those who were given the old treatment. The doctors found that the new treatment was better.

How sure can you be about the results of this study?

Question 27

A review summarized studies comparing playing sports with other ways of making people happy. The review authors included all studies that found that sports improve people’s happiness. Based on these studies, the review authors said that sport definitely improves happiness.

Do you agree with what the review authors said?

Question 28

You find a research study comparing a new medicine with an old medicine for treating ear infections. The study’ authors report on one outcome, pain. They conclude that the new medicine is better than the old medicine. Your friend says that there is a risk that the study authors did not report all of the outcomes.

Is your friend right?

Question 29

Sylvia has breathing problems (asthma). She reads about training to help people with breathing problems take better care of themselves. A systematic review (summary) of studies comparing training to no training shows that the training can help. People assigned to receive training learned more about how to take better care of themselves. Based on this summary, Sylvia concludes that the training will improve health of people with breathing problems.

How sure can we be that the training will improve the health of people with breathing problems?

Question 30

Rebecca and Patrick read about a new treatment in the newspaper. It says that the treatment has a small effect. Patrick says they cannot be sure what that means.

Is Patrick right?

Question 31

A doctor wanted to know if a medicine protects people from getting a heart attack. She did a study and found that half as many people who used the medicine had a heart attack compared to those who did not use the medicine.

What more do you need to know if this was an important difference?

Question 32

A nurse wanted to find out if tea was better than water with honey for treating people with stomach pain. She did a study, and found that the tea lowers the average amount of pain by 2.5 (on a scale from 1 to 100) compared to those who got warm water with honey.

The next time you have a stomach pain; can you expect the amount of pain that you have to be lowered by 2.5, if you try the tea?

Question 33

A new and an old mosquito spray were compared in a research study. In the study, two houses were sprayed with the new spray, and two houses were sprayed with the old spray. Based on this study, the new spray was better for protecting against mosquito bites than the old spray. Neither of the sprays was found to be harmful to people.

How sure can you be about what the study found?

Question 34

In a school, teachers compared how fast children could run with and without eating breakfast. There was little or no difference in how fast the children ran with and without breakfast. This study included 200 children.
The teachers wanted to know if eating breakfast was more helpful for experienced runners, so they looked at the results for the 10 runners who were more experienced runners. The teachers found that eating breakfast was better than not eating breakfast for the experienced runners.

How sure can we be about what the teachers found?

Question 35

Steven says that if the difference between two treatments compared in a study has a p-value of 0.01, the results are very important. Jane disagrees, saying that this just means that the results are statistically significant.

Do you agree with Jane?

Question 36

A teacher wanted to find out if eating oranges keeps children from getting sick. She tossed a coin and divided children into two groups. Children in one group got oranges for breakfast every day; the other group of children did not get oranges for breakfast. At the end of the study, there was no statistically significant difference in how often the children got sick.

Does this mean that there was no important difference in how often the children got sick?

Question 37

Imagine that you often have headaches. You find a systematic review (a careful summary) of all studies comparing a new medicine with other medicines for headaches. The authors of the systematic review conclude that there is a lack of evidence that the new medicine is more effective.

What does this mean?

Question 38

Lots of people in Anita’s school have been having stomach pain. Arnold says they should stop eating so much bread.

Is Arnold right?

Question 39

A doctor did a research study to find out whether tea is better than warm water with honey for children with stomach pain. The doctor found that more of the children who got warm water with honey finished their drinks compared to those who got tea. Based on this study, the doctor said that warm water with honey should be given to children with stomach pain.

Does this mean that warm water with honey is better than tea for stomach pain in children?

Question 40

Doctors did a research study in mice comparing a new medicine for pain with an old medicine. The mice that got the new medicine had less pain compared with mice given the old medicine. The doctors doing the study said that the new medicine was promising and could improve the lives of people in pain.

Which of the following answers is the most correct about whether this new medicine will work the same way in people?

Question 41

A systematic review (summary) found that a new training programme was better than running for people with back pain. In all of the studies included in the systematic review, specialist trainers ran the new training programme.

Are these results relevant to other people with back pain?

Question 42

Martin’s son has a mental disorder. He reads a systematic review (summary) of studies about music therapy, which was shown to be helpful for people like his son. In the studies, music therapy was compared to ordinary visits to a general practitioner. The music therapy was given by trained psychologists, according to a strict schedule in a special clinic. All of the people in the study were closely monitored daily for three months.

How sure can Martin be that this treatment will work as well for his son as it did for the people in the studies?

Question 43

Jane often has headaches. Her doctor tells her that there is a medicine that may help her, but it may harm her. The medicine is also very expensive.

What does Jane need to think about before using the medicine?

Question 44

Two people did a systematic review (summary) of all studies comparing children having sports in school with children not having sports. The review found that, based on the included studies, more children who had sports were happy compared to children who did not have sports. The review authors said this evidence was very certain.

What does it mean that the evidence was very certain?