Heat-related illness symptoms Signs and Symptoms
Conditions
Interventions
The study will not include randomization. All workers from the first company that accepts to participate in the intervention arm will be allocated to the intervention arm. The next company to be recru
Sponsors
Fundacion Privada Instituto De Salud Global Barcelona
Eligibility
Sex/Gender
All
Age
18 Years to 67 Years
Inclusion criteria
Inclusion criteria: 1. Participants must be over 18 years 2. Participants must have access to a smartphone
Exclusion criteria
Exclusion criteria: Not being able to understand Catalan, Spanish or English
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| 1. Heat-related illness symptoms measured using the Heat Illness Symptom Index at the end of the work shift using a validated scale that rates 11 symptoms (e.g., fatigue, cramps, dizziness) from 0 (no symptoms) to 10 (symptoms requiring cessation of work). 2. Average skin temperature during the shift will be monitored using four iButton devices placed at specific body locations (neck, scapula, hand, and shin) and calculated as a weighted average based on established guidelines. | — |
Secondary
| Measure | Time frame |
|---|---|
| Current key secondary outcome(s) as of 26/11/2025: 1. Prevalence of individual heat-related illness symptoms (feeling tired, cramps, nausea, dizziness, thirst, vomiting, confusion, muscle weakness, heat sensations on the head or neck, chills, and feeling lightheaded) during each work shift. Variables will be dichotomized as less than 3 or greater or equal than 3 (presence of symptoms). If the frequencies are not too low, the researchers will also dichotomize at the value of 5 (presence of moderate or severe symptoms). 2. Cognitive performance will be measured at the end of each work shift based on the Stroop test: 1) response time in milliseconds in the incongruent trials; 2) number of correct responses per minute; 3) inhibitory control, calculated as the difference between mean incongruent and congruent reaction time. 3. Self-reported sleepiness measured using the Karolinska Sleepiness Scale (KSS) at the end of the work shift 4. Sleep parameters obtained from Axivity (Ax3) sensor: sleep duration, sleep efficiency, awakenings, and wake after sleep onset. Sleep duration will be calculated as the duration between sleep onset and termination. Sleep efficiency will be defined as the proportion of time spent sleeping from onset to termination: (sleep duration–wake after sleep onset)/sleep duration. Sleep efficiency ranges from 0 to 1, where a score of 1 means the individual did not wake between sleep onset and termination. Awakenings were defined as the number of times a person was awake >5 minutes during the sleep period. Wake after sleep onset will be defined as the sum of the time a person was awake between sleep onset and sleep termination. 5. Time in moderate-to-vigorous physical activity at ambient temperatures greater than 28ºC will be measured with the data provided by the accelerometer (physical activity) and the Wet Bulb Globe Temperature (ambient temperature) throughout the whole of the participation. 6. Perceived exertion (RPE) at the end of the shift measu | — |
Countries
Spain
Contacts
Public ContactXavier Basagaña
Outcome results
None listed