Some people encounter problems when monitoring at home related to the usability of their devices. For instance, the visibility of screens on weighing scales kept in the bathroom can be a problem, as screens or people's glasses get steamed up. People might also take their glasses off when weighing is undertaken before or after showering.

"You have to stare at the... without your glasses on... that's why I asked my Dad for these new digital displays so that I don't need my glasses." Becky, aged 36, participant who measures her BMI

Becky also noted having to get off the scales and bend down to read the screen, complaining about the short length of time the reading was on display. This lead to thinking about alternative ways of making displays visible:

"The idea of having a big number that would flash up at me, I felt that would be useful. I have in the past taken a picture on my phone so I can zoom in later and see what the numbers were. Because it flicks round so quickly and I don't know what that's saying."

Neville was bought a BP monitor by his mother around 6 years ago when they suspected that there might be a health condition in the family. He hadn't expected the gift and suspects his brother also had one gifted. He very rarely used it, and now keeps it without its batteries in a bathroom cupboard.

"It's just been in my bathroom cupboard since then. It's on top of the bathroom cupboard, hence the layer of dust, in a little pouch. The bathroom cupboard is a mirrored one that opens up. It has bugger all in it of use really. I think my ex-girlfriend used to put more stuff in it than I do. I never open it - there are plants on top of it and it's got a mirror on the front." Neville, aged 42 was gifted a monitor but never used it

Gareth displayed a photo where he was using his weighing scales in the shower tray. He explained his reason for this:

"I noticed at the beginning of this I kept weighing differently on the bathroom floor because of the give in the lino. One day I shouted to my wife come and look at this, and I'd put a pound back on in minutes. I realised it has to be hard…So that's when I started doing it in the shower... I lost a few pounds." Gareth, aged 58, participant who measures his BM

Interviews illuminated the experiences of using self-monitoring devices in practice. They revealed insights into the way devices work as well as how people work out what is right or accurate.

Andrea told us she had moved away from an app because it demanded too much attention. She used myfitnesspal to record her calorie intake and had stopped recording her weight because she found she was getting 'obsessive' about it. At that point she told us she preferred to record her weight on a weekly basis in a notebook:

"So although I weigh myself at the minute, I'm not putting into My Fitness Pal because I found I was getting maybe a bit too - I started weighing myself every day and I may have got a little bit too obsessive about it ... I felt I've gradually started being calmer about it …So I thought I'm going to gradually start doing all the things that I used to do again which is weigh myself once a week..." Andrea, aged 27, who measures her BMI

Becky told us she was losing weight together with her sister and sister-in-law. They met on Saturday mornings at Becky's house to take and record their weight, keeping a joint record. Becky explained the Saturday morning routine:

"So usually [my son] will be having his breakfast, the others would come around and we'd have a little weigh-in. Then my son would try and stand on it, and ask why everyone's taking their clothes off, because we'd all take off all the heavy layers to try and get the best result." Becky, aged 36, participant who measures her BMI

Becky had set up a spreadsheet where they recorded their readings by hand. When asked why they did not simply enter the data onto the spreadsheet electronically, Becky stated:

"I think because it was going to be a group thing that we could all jot it down while we were together."

Becky's paper record allows them to do it together. Becky told us that her shared record was pinned to her notice board in her home office. She explained that this was visible enough to remind herself she was trying to lose weight, but not so public that visitors would readily see it.

We found that self-monitoring does not happen all the time. Devices may be kept to hand or in sight when monitoring is desired or being encouraged. Sometimes, self-monitoring devices are not used or forgotten about. Shirley explained how regularly she monitored after she put her device away in the cupboard:

"Interviewer: How often did you take it after that?

Shirley: Oh very occasionally because I actually put it away. When I was doing it obsessively it was on the top of the table. When I got a bit fed up it went underneath the table so I couldn't see it and then it moved from there into the drawer. At that point it wasn't seen, and it could be forgotten. It went out of your face and out of sight and into the cupboard and out of mind." Shirley, aged 68, participant who measures BP and weight

Several of our participants described hiding their monitors from family members as not to worry them, or to protect them from concerns regarding their potential or actual health issues. Edith, was one example:

"Interviewer: So does your daughter know that you own a blood pressure monitor?

Edith: No, I haven't told her. I've chosen not to tell her because she's got enough on her plate, she doesn't need to worry about me." Edith, aged 77, who measures BP, weight and her step count

Monitoring can be integrated into existing daily routines such as sitting in the chair and reading the morning newspaper with a cup of tea - activities of relaxation.

"At 11 o'clock-ish I go and have a cup of tea or a cup of coffee and sit down and just read the paper or do something and I'd just think 'oh, I'll take my blood pressure' and then I'd like do it at night, you know you get sat down, you know after you've had your tea and you're watching the television, I used to have it on the table at the side of my chair. So it was just sort of like easy to whip it on and you know pump it up." Shirley, aged 68, participant who measures BP and BMI

Healthcare professionals are very aware of the problem of white coat hypertension (a higher reading due to being in a clinical setting). They suggest that monitoring at home can provide relaxing effects and offer home monitoring as a way to achieve proper blood pressure readings. This means that monitoring in the comfort of your own home without breaking your own daily routine, can be seen as helpful to getting accurate results. However, this can sometimes clash with the clinical guidance which advises against having hot drinks before taking a blood pressure reading.

Several of our participants explained that they kept their records on kitchen calendars. For example, Helen explained how her doctor advised her to take readings, and how she turned this into her own daily practice.

"Helen: Yeah, I think the doctor said actually take three readings and give the average.

Interviewer: Right. So would you work out the average or would you just stick the three readings...?

Helen: No, just take the three and then choose the one...put the lowest one down. And I'd just copied it.

Interviewer: Yeah. And did you write it down...you said you put it onto a calendar?

Helen: Well, I had an old calendar, so I put it on for each day of the month.

Interviewer: And then did you transfer that onto something else?

Helen: No, I'd take in the calendar for him to look at." Helen, aged 41, participant who measures her BP

Where our participants were older couples, it did not come as a surprise that looking after their health was done together. For example, Jane and Oliver were both in their 70s and had lived together for many years. Jane took blood pressure medication and had type 2 diabetes. Oliver was less concerned over his health until he had a stroke which left him with impaired movement. Together, they maintained their health with a weekly routine of helping each other.

"Jane: [The doctor] said, don't get stressed about it... when we have a check-up, we just take our readings in and they input them into their computer. Oliver usually does it first and then he comes and reminds me it's time to do our blood pressure.

Oliver: Well, normally you go shopping, don't you, about 10 o'clock on a Saturday? So I'll normally go and get it about 9-ish, do it then. Because [Jane] has to put the cuff on for me, I can't do it because...

Jane: And Oliver has to have his done on his right arm... because of the stroke."

Jivan described his partner, who is a doctor, encouraging monitoring after he purchased a blood pressure monitor.

"Interviewer: Was there a period of time when you were using it regularly?

Jivan: Yeah, that was probably influenced by my partner who is a medic, she was worried about my health, my weight and my diabetes. So we keep it on the side and she would see it every other week and say, 'Let's do your blood pressure quickly." Jivan, aged 50, participant who measured his BP and weight

Jivan's wife shows her care by encouraging Jivan to monitor but tries to do this in an unobtrusive way.

Jack described putting away his monitor 'to make the condition disappear' for himself:

"Jack: This last measurement there June 2011 was probably the last time.

"Interviewer: Okay so what changed, why did you stop?

Jack: I felt like the machine might have been a stress contributor. I sort of wanted to make the condition disappear and not have it as a daily thing. It doesn't make you feel ill, but it makes you feel like someone who is ill when you have to use it, and having a medical item lying round in your bedroom when you're 20 something. So, I ditched it and put it back in the suitcase." Jack, aged 27, participant who measures his BP

People's interest in self-monitoring comes and goes for different reasons.

Mandeep explained how he has checked his weight regularly over the last 4 years, using a set of scales that he and his partner had 'hiding under the cupboard in our bedroom'. We asked why and he explained:

"I think we put [our scales] there, just because it's somewhere to put it. When we first got it, the kids had fun jumping up and down on it and standing on it and standing on together and whatever, but they're not interested and that's good because we don't want them to be particularly interested. They're 10 and 13, I mean our 13-year-old is probably at the age where you start thinking a bit about that kind of thing but again, she's not…I mean weight is a very specific measure, isn't it? Scales are a strange thing to have really, because it's how you perceive yourself to a certain extent. The [children] haven't shown much interest in the scales." Mandeep, aged 44, participant who measures weight and BMI

Several of our participants explained how they wished to protect family members from self-monitoring. In particular, strategies were employed to protect vulnerable members of the family, such as children, from monitoring too young or being concerned with their health unnecessarily.

Nora took lots of photos to show how she took her blood pressure readings in different rooms depending on where her partner was. In the evenings, she took it in front of the telly when her partner was in bed and in the mornings she takes the reading in bed when her partner has got up. She also took a photo of her bedroom door which led out to the hallway. She explained why:

"I'd been to the pub and I was taking a reading, which you're not supposed to do when you take alcohol, but anyway...I literally sat on the floor outside my bedroom door, which is only what a drunk person would do, because obviously it's not really any less noisy. I could have taken my blood pressure literally anywhere, but what I chose to do was to collect the monitor which generally lives on my bedside table, and then I sat on the floor immediately outside my bedroom. ...I thought it would wake my partner up if I did it in bed." Nora, aged 36, participant who measures her BP

Nora's jovial account shows how monitoring is done with partners in mind, considering how monitoring may disrupt their co-habiting lives. The account of her monitoring in the hallway after a few drinks also tells a story of the ideals of monitoring, versus the monitoring done in people's everyday lives.

We found that some participants carry their self-monitoring devices with them in their bag to monitor on the go. Joanne explained how she carried her BP monitor in her handbag so it was always to hand, and sometimes monitored 'in secret'.

"I'd do it when nobody was in the house which is always sort of embarrassing because they were like what you doing with that again and you need to give over, it's got ridiculous, and it had really. I would just take it with me all over. So it was something I did secretly because I was embarrassed, because I knew it was a bit of a weird thing to do, but it's like I needed that assurance." Joanne, aged 35, participant who measures her BP

For Joanne, monitoring in private was related to avoiding disapproval of her family who thought she was overly concerned about her blood pressure, her feelings that high blood pressure was a result of her lifestyle choices and the embarrassment of how monitoring was related to her anxiety and panic attacks. Joanne's account is unusual but it is important because it illustrates that family and personal networks may not always support self-monitoring, and that the presence of a monitor may open up sensitive issues to unwanted scrutiny.

Some participants told us that they recorded their readings on their phones because it is always with them, unlikely to be forgotten or was simply convenient. Ayo, for example, explained that she used to go to the pharmacy to weigh herself and recorded her weight in her smart phone, firstly as a memo in her old 'Blackberry' phone, and then in a health app that came free with her new Samsung phone.

"They [pharmacy] print out a slip of paper and then I used to record it in my phone... It was just a memo... If I put it in the notebook I felt I could lose it. That was the way I could keep tabs... because my phone was always with me... I had those sheets, but I could lose them. I would probably have to staple them all together..." Ayo, aged 33, participant who measures her weight and BMI