When you join the study, we will ask you to wear a physical activity monitor on your wrist for 7 days to measure your day-to-day physical activity. If you have worn a physical activity monitor as part of the INTERVAL study, you will not need to do this again at the start. However, we will ask everyone taking part to wear a monitor again 12 weeks later.
- What does the activity monitor measure?
The activity monitor records information about the duration, frequency and intensity of all kinds of activity (from sleeping to vigorous physical activity). It does this by measuring acceleration in three directions (up/down; forwards/backwards; and left/right). Scientists will be able to determine how active a person has been based on the information collected by the activity monitor.
- How long do I have to wear it?
Please put it on as soon as it arrives and try to wear it continuously until the date given in the enclosed letter.
- On which wrist should I wear it?
It is preferable to wear the monitor on the wrist of the hand that you would use to throw a ball. But, if this is not possible for some reason then please wear it on the other wrist.
- How will I know if it is working?
The activity monitor is set up to turn itself on and off automatically. As it is completely silent, you will not be able to tell that it is running.
- What is the monitor made of, and might it cause an allergic reaction on my wrist?
The activity monitor is made of moulded thermoplastic and the strap is hypoallergenic. A mild reaction, e.g. itchiness, may be experienced if you have an allergic reaction to plasters, but there are no other risks associated with wearing the activity monitor.
- I was away for a few days when the monitor arrived. Is it still worth wearing?
Yes, provided it is still before the return date given in the letter. If it is after that date, please return the device to us with a note to say that you were unable to wear it. Unfortunately we will not be able to replace it with a new one.
- Do I need to take it off for certain activities?
The device is robust and water-proof, and has been designed to be worn when working or sleeping, having a bath or shower, or playing all types of sport, including swimming. Extremes of temperature may damage the battery though, so it should be taken off if you have a sauna.
- What if I have to take off the monitor?
If you need to take the monitor off for some reason please put it in a stationary place, e.g. in a drawer, not in your bag, and then put it back on as soon as you can.
- My job does not allow me to wear accessories: can I still take part?
Yes. Please remove the activity monitor if you are required to do so for work, but don’t forget to put it back on again afterwards.
- Can I take the activity monitor with me when I go on holiday?
Yes. You can put the monitor on your wrist and forget about it. It is also safe to pass through airport security. But please do not forget to return it to us after the date given in the enclosed letter when you get home.
- Can I wear the monitor for longer than the date given in the enclosed letter?
The monitor turns off automatically after the date given in the enclosed letter. Please return it to us as soon as possible after that date in the stamped addressed FREEPOST envelope provided.
- What should I do if I lose the activity monitor or it breaks?
Donít worry. If the device breaks just return it to us in the envelope provided. We are able to retrieve any information that has already been collected. If you lose the device please let us know by telephoning free of charge 0800 021 7182 (Mon-Fri; 9:00am-5:00pm).
- How secure is the information on the monitor; suppose it gets lost in the mail?
The activity monitor does not contain any information that can identify you. A special code number on each device is matched with your ‘participant ID number’, and the key to this code is known by the INFORM study data manager only. Your personal details and data about your health and lifestyle are stored separately. Other security mechanisms are also used to protect your privacy.
- How do I return the activity monitor?
Please post the device back to us as soon as possible after the date given in the enclosed letter. All you need to do is put it into the stamped addressed padded envelope provided, seal the envelope and put it in a post box. The cost of postage is already paid.
- What should I do if I cannot find the return envelope?
Don’t worry. You can return the activity monitor to us in a padded envelope using our FREEPOST address:
Strangeways Research Laboratory
2 Wort’s Causeway
Cambridge CB1 8RN
Many thanks for your help. If you need any further advice, please telephone the study team on 0800 021 7182 Monday-Friday 9am-5pm (free from most landlines).