Mind training, stress and behaviour—A randomised experiment

In this paper, we evaluate the effects of a psychological training, called Mindfulness-Based Stress Reduction (MBSR) on stress and risk and time preferences. MBSR is a well-known psychological technique, which is believed to improve self-control and reduce stress. We conduct the experiment with 139 participants, half of whom receive the MBSR training, while the other half are asked to watch a documentary series, both over 4 consecutive weeks. Using a range of self-reported and physiological measures (such as cortisol measures), we find evidence that mindfulness training reduces perceived stress, but we only find weak evidence of effects on risk and inter-temporal attitudes.

 You must be older than 18 years old, student at the University of Edinburgh, with NO medical condition

Possible time slot options (you can only choose one option and are asked to stick to the days and times once you have picked that option)
Option Q2 This survey aims to collect information on various aspects of your lifestyle and activities in the previous week. The survey takes around 30 minutes to complete. All data collected in this survey will be held anonymously and securely, and will be used for research purposes only.
Please click next to continue.
Q3 Please enter your participant ID. This is the code consisting of letters and numbers on the card you were given at registration. Please don't put any spaces between the letters and numbers.
Q4 We would like to ask you some questions about your feelings on aspects of your life. There are no right or wrong answers. For each of these questions we'd like you to give an answer on a scale of 0 to 10, where 0 is 'not at all' and 10 is 'completely'. 0 (1) 1 (2) 2 (3) 3 (4) 4 (5) 5 (6) 6 (7) 7 (8) 8 (9) 9 (10) 10 (11) Overall, how satisfied were you with your life in the previous week? (1) Overall, to what extent do you feel that the things you did the previous week were worthwhile? (2) Overall, how happy are you these days? (3) Overall, how happy are you right now?
Q97 How many hours did you spend studying the previous week? Do NOT include hours spent in classes, but DO include hours spent studying alone, in the library or with classmates.
Q98 Did you have any midterm exams in the previous week?  Yes (1)  No (2) Q99 Did you have to submit any assignments in the previous week?  Yes (1)  No (2) Q100 Did anything unusually upsetting or stressful happen to you in the previous week?  Yes (1)  No (2) Answer If Did anything unusually upsetting or stressful happen to you in the previous week? Yes Is Selected Q101 Please provide some details.
Q5 The next questions are about your health behaviours during the PREVIOUS WEEK.
Q102 Please read all the following statements carefully and tick the box next to the one that best describes you. During the previous week:  I did not smoke any cigarette, not even a puff (1)  I smoked cigarettes, but fewer than one per day (2)  I smoked between 1 and 10 cigarettes per day (3)  I smoked between 10 and 20 cigarettes per day (4)  I smoked more than 20 cigarettes per day ( Q17 How many servings of fruit did you eat yesterday? One serving is about one cup of chopped or sliced fruits, or one medium sized apple of banana.
Q18 Not counting potatoes, how many servings of vegetables did you eat yesterday? One serving is about one cup of chopped or sliced vegetables.
Q19 How often did you drink coffee, latte or cappuccino (not decaf) in the previous week?  Never (1)  About once a week (3)  Every 2 or 3 days (4)  Once a day (5)  Twice a day (6)  At least three times a day (7) Q25 The next questions are about drinking alcohol, including beer, wine, spirits and any other alcoholic drink.
Q26 How many days over the previous week did you have an alcoholic drink?  Almost every day (1)  Most days a week (2)  About once or twice (3)  Never (5) Q27 On the days that you did drink during the previous week, how many drinks did you have, on average? One drink is a glass of wine, or a pint of beer or cider, or 25 ml of spirits.
Q28 How often did each of the following happen to you during the previous week?
All of the time (1) Often (2) Sometimes (3) Rarely (4) Never (5) Felt completely out of control when it came to food. (1) Ate too much because you were upset, nervous or stressed. (2) Ate too much because you were bored or felt lonely. (3) Ate so much food so fast that you didn't know how much you ate or how it tasted. (4) Ate more than usual while preparing for an exam or working on an assignment. (5) Ate high calorie snacks while studying or working on assignments. (6) At what time did you go to sleep most days during the previous week? (7)  after 2am (8) Q34 On average, how many hours of sleep did you get in a 24 hour period during the previous week?
Q35 How did you relax during the previous week?

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Appendix G: Summary Statistics of the Stressful Tasks

Appendix H: The Impact of MBSR on Health-related Behaviours and Eating Habits
We collect a number of measures related to eating and healthy eating, in particular. First, we construct summary measures of unhealthy food consumption, counting the number of unhealthy items participants report having consumed the previous day (from a list we provided; see Appendix C for details), and using the binary indicators of avoiding foods high in fat or cholesterol, and trying to eat foods high in fibre. Second, we focus on measures related to "emotional" or "comfort eating" based on the Compulsive Eating Scale (?).
Next, we have measures (based on self-reports) of the frequency of smoking and alcohol consumption, as well as the average number of hours slept. In Session 1, the respondents were asked generally about their smoking and drinking habits, while, in the other sessions, the questions referred to the previous week. The detailed weekly questions can be found in Appendix C.
We also collected a measure of preferences for "healthy foods", using a revealed preference approach. Participants were asked to make a real choice between a high-calorie and a low-calorie option. Each option is a combination of a snack and a drink. Participants were first asked to choose sequentially among three high-calorie snacks, three high-calorie drinks, three low-calorie snacks and three low-calorie drinks. We then constructed a low-calorie option by combining their preferred low-calorie snack with their preferred low-calorie drink, and a high-calorie option by combining their preferred high-calorie drink and high-calorie snack. Participants were endowed with £4 and asked to pick between the high-and low-calorie options, each of them associated with different prices. The options are listed Appendix D. The price of the chosen item would be deducted from the £4 endowment. They were asked to choose between their preferred highand low-calorie options at different prices. 1 We construct a measure of preference for the low-calorie option, which corresponds to the number of times participants choose that option rather than the high-calorie option. 138 138 138 *, **, *** indicate significance levels at 10%, 5% and 1% respectively   *, **, *** indicate significance levels at 10%, 5% and 1% respectively