1.1 Quick revision
We recommend trying these Quick revision questions before your tutorial.
Consider this RQ:
For London take-away restaurants, is the average amount of salt in a Chinese meal the same as in an Indian meal?
- What type of RQ is this?
- What is the Outcome in this RQ?
- What would be the response variable?
- What would be the unit of analysis?
- What would be the unit of observation?
- The article states that "a takeaway meal was defined as food purchased from out of home food outlets or ordered for home delivery" (p. 518).
What type of definition is this?
- Relational: There is a comparison (between Chinese and Indian meals), but this is not an interventional (as the researchers did not determine whether a meal was Chinese or Indian).
- The Outcome refers to something quantitatively measured in a group (such as an average or percentage) that is the outcome or result of the comparison.
- A variable is measured on an individual; in this case, the amount of salt in the individual meals.
- The unit of analysis depends on how the data were collected.
Any given restaurant probably uses salt in a similar way, so if many meals were taken from each restaurant, the restaurant would be the unit of analysis.
Or perhaps restaurant chains were used and restaurants in the same chain are likely to operate in a similar way, and the restaurant chain would be the unit of analysis.
Or it may be the individual meals. We need more information.
- The unit of observation is the meal, as the salt content must be assessed from each individual meal.
Jaworowska A, Blackham T, Stevenson L, Davies IG. Determination of salt content in hot takeaway meals in the United Kingdom. Appetite. 2012;59(2):517–22.