P2B: SLT (Lowe)
Below you will see a sample response to a question on Paper 2, Section B. This question will always ask you to evaluate a study using two or more of four to six concepts.
It is best if you attempt to mark the question yourself before reading the “Examiner's notes” at the bottom of the page.
The study: Lowe et al. (2004)
Lowe et al. (2004) investigated the role of social learning in promoting healthy eating among British schoolchildren, with the specific goal of increasing consumption of fruits and vegetables.
The sample comprised 749 children aged 5-11 years in two inner-city London primary schools. One school served as a control; the other received the experimental intervention, the Food Dudes Program.
At the start of the study, fruit and vegetable consumption was measured to establish a baseline. The researchers used three key measures.
- Children in both schools were given the option of consuming fruit and vegetables at lunchtime. Their choice of foods was observed and recorded on a five-point rating scale.
- The younger children (ages 5 - 7) received fruit at snack time. The weight of the fruit consumed was recorded.
- Questionnaires were given to parents, asking them to recall the eating behaviors of their children.
Consumption levels would again be measured during the intervention and four months after the completion of the program.
Over 16 days children watched video adventures featuring the Food Dudes. The Food Dudes are young superheroes who are involved in saving the world from the “Junk Punks,” who plot to destroy the world by depriving it of fruit and vegetables - and thus, its key energy force. The Food Dudes not only continue to beat the “Junk Punks,” but they are seen eating a range of fruit and veg, explaining how wonderful they taste - and showing that they are the key to their power in defeating the bad guys.
In addition, the children were given a “Food Dudes’ Home Pack,” which encouraged them to eat more fruit and vegetables at home and have their parents record what they were eating.
The researchers found a significant increase in fruit and vegetable consumption both at school and at home among children in the experimental condition. The greatest increase was seen in the children who, at the beginning of the study, had shown the lowest consumption rates of fruit and vegetables. For example, during snack time, these children went from eating just 4% of the fruit they were given to 68% after watching the Food Dudes series. Four months later, they were still eating 12 times as much fruit as they had originally and 4 times as many vegetables. In the control school, where the same fruit and vegetables were offered to students, but without the Food Dudes intervention, there was no change in their consumption rates.
Question
Discuss Lowe et al.’s (2004) with regard to two or more of the following concepts: Bias, causality, change, measurement, perspective, or responsibility.
Student response
Lowe et al. (2004) investigated whether the Food Dudes intervention could increase healthy eating among primary school children. The study can be discussed in relation to the concepts of causality, change, and bias. These concepts help us evaluate the effectiveness of the intervention and the extent to which the findings can be trusted.
Causality refers to whether one variable directly causes a change in another. In Lowe et al.'s study, the researchers wanted to determine whether the Food Dudes intervention caused children to increase their consumption of fruits and vegetables. The use of an experimental and control group strengthens the argument for causality. Both groups were offered the same fruits and vegetables, but only the experimental group received the intervention. Consumption increased significantly in the experimental group, while there was no change in the control group. This suggests that the intervention was responsible for the change in eating behavior.
In addition, the children were randomly assigned to the conditions. One school received the intervention and the other acted as the control group. However, there could be difference between the two schools. For example, teachers in the experimental school may have been more enthusiastic about encouraging healthy eating. Therefore, although the study supports a causal relationship, other variables cannot be completely ruled out. This lowers the validity and reliability of the study.
The concept of change is also relevant because the researchers investigated whether children's eating behavior could be changed and whether these changes would last. The results showed that children increased their fruit and vegetable consumption, particularly those who initially ate very little. For example, their fruit consumption at snack time increased from 4% to 68%. This suggests that the intervention was especially effective for children with initially low consumption.
The researchers also measured consumption four months after the intervention. Children were still eating significantly more fruits and vegetables than before the program. This suggests that the intervention may have helped children develop healthier eating habits rather than simply changing their behavior while watching the videos. However, four months is a relatively short follow-up period, so it is unclear whether the changes would continue over several years.
Bias may also have influenced the findings. One potential source was social desirability bias in the parental questionnaires. Parents may have reported that their children ate more fruits and vegetables because they knew this was the goal of the intervention. This could have led researchers to overestimate the program's effectiveness at home.
However, the researchers also used more objective measures, such as weighing the fruit consumed at snack time. This reduced reliance on parental reports and strengthened the credibility of the findings. Another limitation is that the sample came from only two inner-city London schools. The findings may not generalize to children from different cultural or socioeconomic backgrounds.
In conclusion, Lowe et al.'s study provides evidence that the Food Dudes intervention can encourage positive changes in children's eating behavior. However, a limited follow-up period and potential bias mean that the findings should be interpreted with some caution.
505 words
Examiner feedback
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Conceptual understanding: The response demonstrates some good understanding of three concepts: causality, change, and bias. However, there is a misunderstanding of random allocation. The two schools were randomly allocated, but individual participants were not. This means the study is quasi-experimental. The conclusion that this “supports causality” is not correct. (10 - 12).
Critical analysis: The response identifies relevant strengths and limitations of the study. These points are linked to the study and used to support the discussion. However, the analysis lacks development. For example, the student identifies possible confounding variables but does not fully explain how they might provide alternative explanations for the results. The conclusion is consistent with the arguments presented but is relatively simple (10 - 12).
Psychological terminology: Psychological terminology is mostly used accurately and appropriately. Some terms are not, however, used effectively. For example, social desirability effect. What is actually being described is expectancy effect. The use of the terms “validity and reliability” is not effective. (10 - 12).
Total: 11 marks