The goal of this observational study is to learn the feasibility of using a mobile application "Stressometer" to measure perceived stresss levels several times per day. The study will also explore if the stress scores collected with the application are similar to results from standard questionnaires about stress, anxiety, and depression.

The main questions it aims to answer are:

Can participants regularly report their stress four times a day for two weeks using the mobile application? Do participants find the application easy and acceptable to use? Are stress scores collected with the application related to scores from validated questionnaires on stress, anxiety, and depression?

Participants will:

Use the Stressometer mobile application to rate their stress level four times per day for 14 days Complete questionnaires about stress, anxiety, and depression at the beginning and/or end of the study Provide feedback on how easy and acceptable the application is to use

Researchers will use this information to understand whether this mobile tool is practical for measuring stress in daily life and whether it provides results similar to established psychological questionnaires.

Stress is a dynamic psychological state that can fluctuate throughout the day. Traditional methods for assessing stress, such as validated psychometric questionnaires, typically rely on retrospective reporting and may not fully capture short-term variations in perceived stress. Mobile health technologies approaches offer the opportunity to measure stress in real time and in naturalistic settings.

The Stressometer is a mobile application developed to allow rapid and repeated self-assessment of perceived stress using a simple numeric scale. However, the feasibility of using such a tool multiple times per day over a sustained period, as well as its relationship with established psychometric measures, remains to be established.

In a preliminary study, feasibility was investigated in a sample of 30 healthy student participants. Participants were instructed to report their perceived stress level using the Stressometer application four times per day (morning, midday, evening, and bedtime) over a 14-day period. Compliance with repeated assessments and participant engagement were monitored throughout the study.

In addition to mobile-based stress assessments, participants completed validated psychometric questionnaires evaluating stress, anxiety, depression, and well-being. Mean stress scores obtained via the Stressometer were subsequently analyzed and correlated with questionnaire-derived scores to assess convergent validity.

This study aims to further evaluate the feasibility of intensive longitudinal stress measurement using a mobile application, focusing on compliance rates and user acceptability. It also seeks to examine the relationship between real-time stress ratings and standardized psychological measures, in order to determine whether the Stressometer provides a reliable and ecologically valid assessment of perceived stress in daily life.

Inclusion Criteria:

Participants must meet all of the following criteria to be eligible for inclusion in the study:

• Enrolled as a university student
• Aged 18 years or older
• Possession of a smartphone compatible with the Stressometer application
• No self-reported psychiatric condition that could interfere with study participation or data collection
• Willingness to participate and provision of non-opposition to participate in the study

Exclusion Criteria:

Participants will be excluded if they meet any of the following criteria:

• Presence of any acute or chronic medical condition that may interfere with study participation or data interpretation, including but not limited to psychiatric disorders, severe sleep disorders, endocrine or metabolic diseases, cardiovascular diseases, neurological conditions, acute or chronic pain, respiratory diseases, substance use disorder or addiction, or current pregnancy or postpartum period
• Individuals deprived of liberty by judicial or administrative decision
• Individuals currently receiving compulsory psychiatric care
• Refusal to participate in the study

The study will include healthy adult university students aged 18 years or older. Participants will be recruited from a university setting and must be able to use a compatible smartphone to complete repeated stress assessments via a mobile application over a two-week period. Individuals with medical or psychiatric conditions that could interfere with participation or data interpretation will be excluded.

IPD will not be might not be shared publicly due to privacy and data protection concerns.