How do everyday events shape the well-being of adults over 65?
Most of what we know about stress and emotions in later life comes from studies that compare older adults with younger ones, or that ask people to look back over weeks or months. These approaches miss what happens from one day to the next. They also treat “older adults” as one group, although people aged 65 and people aged 90 can live very different lives.
The ZWÄG 65+ study asked 108 Swiss adults aged 65 to 92 to complete a short diary every evening for 14 days in the Avicenna app (then Ethica). Each evening they reported the stressful and positive events of the day, how they felt, how old they felt, and other aspects of their day. The same 14 days of diaries have since answered several different questions, from how older adults react to daily stressors to whether humid days make them feel lonelier.
The study was run by researchers at the University of Zurich, with Theresa Pauly, now at Simon Fraser University, as senior author on all of its papers. Data were collected from June to September 2022.
A short daily diary, set up in person, can give near-complete data from adults in their seventies, eighties, and nineties.
Study at a Glance
| Study feature | Detail |
|---|---|
| Study design | App-based observational daily diary study |
| Population | Community-dwelling adults aged 65 and over living in Switzerland |
| Participants | 108 (aged 65–92, mean 73; 58% women; all retired) |
| Recruitment | Flyers, mailing lists, and newsletters; 108 of 123 interested people took part (88%) |
| Data collection | June to September 2022 |
| Daily diary | One end-of-day survey for 14 days, prompted at 8:30 p.m. with a reminder at 9 p.m. |
| Diaries completed | 1,429 of 1,512 possible (95%); no participant withdrew |
| Measures | Daily stressors, positive events, positive and negative affect, subjective age, savoring, loneliness, depressive symptoms, and physical symptoms |
| Language | German |
| Tools | Avicenna (then Ethica), R, Mplus |
| Open science | Preregistered analyses; data and code shared on OSF |
| Ethics approval | Ethics Committee of the University of Zurich |
How the Study Worked
Eligibility and Baseline Session
People aged 65 or over with Swiss residency could take part if they were willing and able to use a mobile device and could read newspaper-sized print. People with a diagnosed neurodegenerative disease, or with physical impairments that would make it hard to use a touchscreen, were not eligible.
After a telephone screening, participants came to the University of Zurich in small groups of one to five people. They gave consent, the research team installed the app on their own phone or tablet, or on a device provided by the study, and they completed a baseline questionnaire on their background, health, and personality. Each group then received instructions for the diary period, which started the next day.
One Diary Every Evening
For 14 days, the app prompted a short diary at 8:30 p.m., with an automatic reminder at 9 p.m. Participants completed it before going to bed. The diary asked about the whole day:
- Stressors: Whether they had experienced a stressful event in each of seven areas, such as an argument, a health problem, or something that happened to a close friend or family member.
- Positive events: Whether they had experienced a positive event, such as an in-person or remote social interaction, time in nature, or a good event at home.
- Affect: How happy, calm, content, distressed, sad, or tense they had felt since waking up, each rated on a 0–100 slider.
- Subjective age: “How old do you feel today?”, answered with a number.
- Other measures: Savoring of positive experiences, loneliness, depressive symptoms, physical symptoms, and time spent alone.
What the Study Found
So far, five papers have used the ZWÄG 65+ diaries:
- Solitude and time-savoring: The first paper from the dataset, written as a master’s thesis. On days when participants spent more time alone than usual, they reported more depressive mood and loneliness, but not more physical symptoms. These links were weaker on days when they savored their time more than usual.
- Daily stressors and age: Even within this older group, age mattered. Financial and traffic stressors were more strongly linked to daily mood, and health stressors to physical symptoms, among the oldest participants. Social stressors had similar effects at every age.
- Subjective age: On average, participants felt about 8 years younger than their actual age, but this changed from day to day. On days when they felt older than usual, they reported more stressors, fewer positive events, and stronger emotional reactions to both.
- Savoring: On days when participants savored positive experiences more, a stressor was no longer followed by a clear rise in negative mood.
- Humidity and loneliness: By matching each diary day with data from a local weather station, the researchers found that participants felt lonelier on more humid days. This held only for those who were not married.
Stressors occurred on about a third of days, and positive events on 95% of days.
Why the Data Were So Complete
Participants completed 95% of their diaries, and none dropped out. Several choices in the design likely helped:
- In-person setup. Installing the app at the university, in small groups, meant every participant left with a working app and knew what to expect.
- Any device. Participants could use their own phone or tablet, or borrow one, so not owning a smartphone was not a barrier.
- One short survey a day. A single evening diary fits into a daily routine more easily than several prompts during the day. The researchers chose a daily schedule because many of the events they were interested in, such as stressors, rarely happen more than once a day.
- A reminder half an hour later. The 9 p.m. reminder gave participants a second chance without adding more surveys.
Because the diary covered many aspects of daily life, and because the data were shared openly, the same 1,429 diaries could answer questions about solitude, stress, aging, savoring, and the weather.
Where Avicenna Fits
Avicenna delivered the evening diary for 14 days, with an automatic reminder for each one. The app ran on participants’ own phones and tablets and on devices provided by the study, and all questions were presented in German.
Because each diary was dated and linked to the participant, the researchers could compare each person’s days with their own average, test whether one day’s subjective age predicted the next day’s events, and match each day with external weather data.
In Their Words
We asked Theresa Pauly, the senior author of the ZWÄG 65+ papers, about running the study.
What advice would you give researchers planning a daily diary study with older adults?
“Building rapport is particularly important when working with older adults. If possible, I would recommend an initial in-person meeting and a practice day before the start of data collection. It can also be helpful to schedule a phone call during the practice period to ensure everything is working properly. Going through the questionnaire together beforehand allows participants to ask questions and clarify anything they do not understand, which can improve both compliance and data quality.”
Was anything about running the study easier or more difficult than you expected?
“The study was easier to run than expected overall. The app functioned well, and it was especially helpful that participants could complete surveys offline when needed.”
Looking back, what did Avicenna make possible that would have been difficult to do otherwise?
“Avicenna allowed us to set up the study and launch data collection very quickly, within approximately one month. This efficiency was particularly valuable because it enabled us to complete data collection in time for my student to analyze the data and finish her master’s thesis within the required timeframe.”
Research Team
Theresa Pauly, PhD
Senior author
University of Zurich; now at Simon Fraser University
Shira Peleg
First author (daily stressors; savoring)
University of Zurich
Patrick Klaiber
First author (subjective age)
Tilburg University
Miriam Wallimann
First author (solitude and time-savoring)
University of Zurich
Publications
- Time-savoring moderates associations of solitude with depressive mood, loneliness, and somatic symptoms in older adults’ daily life. Wallimann, M., Peleg, S., & Pauly, T. (2024). Applied Psychology: Health and Well-Being, 16(3), 1497–1515.
- Associations between Daily Stressors, Health, and Affective Responses among Older Adults: The Moderating Effect of Age. Peleg, S., Wallimann, M., & Pauly, T. (2024). Gerontology, 70(11), 1213–1226.
- Daily Fluctuations in Subjective Age among Older Adults: Links with Stressors, Positive Events, and Emotional Reactions. Klaiber, P., & Pauly, T. (2025). Gerontology, 71(3), 239–251.
- Savouring Moderates Affect Reactivity to Daily Events in Old Age. Peleg, S., Wallimann, M., & Pauly, T. (2025). Stress and Health, 41(2), e70030.
- Daily Association Between Ambient Humidity and Loneliness in Older Adults: The Role of Depressive Symptoms and Marital Status. Oduro, J. K., Michalowski, V. I., & Pauly, T. (2026). International Journal of Behavioral Development.
- ZWÄG 65+ study materials, data, and code. Open Science Framework.
Planning a Similar Study?
Avicenna supports daily diaries at a fixed time with automatic reminders, studies in German and many other languages, and slider and numeric questions. Its Weather data source can also record conditions such as temperature and humidity at each participant’s location. Explore the documentation to learn how to set up these components:
For questions about study design, data collection, or the right setup for your research, explore Avicenna’s features and integrations or talk to our team.