Clinical trial NCT05096000: InterMob: a Randomized Controlled Trial Aimed at Reducing Car Use in Regular Car Users
Official title: InterMob: a Randomized Controlled Trial Aimed at Reducing Car Use in Regular Car Users by Combining Hard and Soft Levers
Study type: INTERVENTIONAL
Overall status: ENROLLING_BY_INVITATION
Phase: NA
Conditions: Automobile Driving
Active Commuting
Keywords: Transportation
Active transportation
Sustainable transportation
physical activity
air pollution
Lead sponsor: Université Joseph Fourier
Sponsor class: OTHER
Collaborators: name: IDEX - Univ. Grenoble-Alpes
name: Région Auvergne-Rhône Alpes
name: Institut de Recherche en Santé Publique, France
name: ADEME
name: Institut National de la Santé Et de la Recherche Médicale, France
name: Métropole Grenoble-Alpes
First posted: 2021-10-27
Enrollment: 400
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: Regular car use is a source of pollution and physical inactivity. InterMob is an interdisciplinary randomized controlled behavioral intervention aiming at reducing car use. The objectives of InterMob are to a) Evaluate the efficacy of a theory- and evidence-based intervention, b) Identify the mechanisms related mobility change, and c) Identify the conditions under which the intervention is effective.

To meet these objectives, 300 regular car users living in Grenoble will be recruited and randomized in one of two arms:

1. experimental group that will receive the InterMob intervention: six months of free public transport/access to a bicycle, and behavior change techniques (personalized transport advice, setting of mobility change goals, considering possible obstacles; 6 months of motivational messages to prompt goal setting and self-monitoring).
2. active control group that will receive information about air pollution (discussion about the health consequences of air pollution, the association between air pollution and car use; 6 months of messages to prompt air pollution monitoring.) Follow-up measures will be carried out until 24 months after the beginning of the study (8-day measurement sessions). Five sessions will involve wearing a GPS/accelerometer, and an air pollution sensor. Participants will complete mobility logs and questionnaires measuring the psychological mechanisms related to their mobility (habits, intentions, self-efficacy), and socio-economical characteristics (number of children, accessibility) during the 8 sessions.

The investigators hypothesize that the participants allocated to experimental group will reduce the car use and increase the use of alternative modes to the car (biking, walking, public transport, and carpooling) more than the participants of the control group, and that these changes will remain. The investigators hypothesize that mobility changes will be mediated by intention and self-efficacy. The investigators hypothesize that the efficacy of the intervention will be moderated by socio-spatial factors (number of children, travel distances) and psychological factors (self-control).

The main criterion will be car use reduction and the use of alternative modes to the car. In addition, the investigators will assess physical activity (minutes of moderate-to-vigorous physical activity), the exposure to air pollution, the quality of life and the carbon footprint associated to transport.

Detailed description: Sample size : The investigators have calculated the sample size considering :

* the proportion of trips made by car (49% of the trips made in Grenoble Metropole are made by car according to the EMD, 2010 which is the most recent survey in the area currently available),
* the potential target population's transport behavior (a percentage of the population can be classified as reluctant drivers with positive attitudes toward other modes of transportation, this population makes 80% of their trips and could potentially reduce their car use to 64% considering the characteristics of the trips)
* the impact of past interventions (car reduction of -17%, from 50% to 33% of car use, Brockman \& Fox, 2011).

The investigators considered a statistical power of 0.8, and a significance level of 0.05 for a proportion of 80% or 50% of trips made by car in the control group. In order to detect a difference of 15% when the share of trips made by car is reduced from 80% to 65% or from 50 to 35%, the investigators need 300 individuals (i.e., 150 individuals in each group).

Eligibility criteria: Inclusion Criteria:

* Being at least 18 years old at the time of inclusion

  • Profile: employed / unemployed / retired / on work-study or apprenticeship
  * If employed : Work and live in the SMAAG territory (Metropole of Grenoble + Grésivaudan + Pays voironnais)
  * If in apprenticeship/training program: Working, studying and living in the SMAAG territory (Metropole of Grenoble + Grésivaudan + Pays voironnais)
  * If unemployed / retired : Reside in the SMAAG territory (Metropole of Grenoble + Grésivaudan + Pays voironnais)
* The car/motorcycle/scooter is the main mode of travel during the week (excluding weekends)
* Travels 3, 4, or 5 days by car (excluding weekdays)
* Thinks about reducing car use or has started to reduce car use - Expect to live and work in the Grenoble area in the next 2 years (Very likely and likely options)

Exclusion Criteria:

* Being a student
* Living outside the Metropole of Grenoble + Grésivaudan + Pays voironnais
* Working outside (Metropole of Grenoble + Grésivaudan + Pays voironnais)
* Studying outside (Metropole of Grenoble + Grésivaudan + Pays voironnais)
* Car/motorcycle/scooter is not the main mode of travel
* Travels 0, 1 or 2 days a week by car
* Does not intend to reduce the frequency of car use
* Does not expect to live and/or work in the Grenoble area in the next 2 years

Primary outcomes:
measure: Changes in car use from the baseline and the beginning of the intervention (one month after the beginning of the intervention, Month 1)
timeFrame: Baseline and one month and a half after the baseline (Month 1)
measure: Changes in car use from the baseline and half of the intervention (Month 3)
timeFrame: Baseline, and three months after the baseline (Month 3)
measure: Changes in car use from the baseline the end of the intervention (Month 7)
timeFrame: Baseline and seven months after the baseline (Month 7)
measure: Changes in car use from the baseline and two months after the end of the intervention (Month 9)
timeFrame: Baseline and nine months after the baseline (Month 9)
measure: Changes in car use from the baseline and six months after the end of the intervention (Month 12)
timeFrame: Baseline and one year after the baseline (Month 12)
measure: Changes in car use from the baseline and one year after the end of the intervention (Month 18)
timeFrame: Baseline and one year and a half after the baseline (Month 18)
measure: Changes in car use from the baseline and one year and a half after the end of the intervention (Month 24)
timeFrame: Baseline and two years after the baseline (Month 24)
Secondary outcomes:
measure: Changes in active commuting (classic or electric bike, public transport, walk, carpooling) from the baseline and and the beginning of the intervention (one month after the beginning of the intervention, Month 1)
timeFrame: Baseline and one month and a half after the baseline (Month 1)
measure: Changes in active commuting (classic or electric bike, public transport, walk, carpooling) from the baseline and the half of the intervention (Month 3)
timeFrame: Baseline, and three months after the baseline (Month 3)
measure: Changes in active commuting (classic or electric bike, public transport, walk, carpooling) from the baseline and the end of the intervention (Month 7)
timeFrame: Baseline, and seven month after the baseline (Month 7)
measure: Changes in active commuting (classic or electric bike, public transport, walk, carpooling) from the baseline and two months after the end of the intervention (Month 9)
timeFrame: Baseline, and nine months after the baseline (Month 9)
measure: Changes in active commuting (classic or electric bike, public transport, walk, carpooling) from the baseline and six months after the end of the intervention (Month 12)
timeFrame: Baseline, and one year after the baseline (Month 12)
measure: Changes in active commuting (classic or electric bike, public transport, walk, carpooling) from the baseline and one year after the end of the intervention (Month 18)
timeFrame: Baseline, and one year and a half after the baseline (Month 18)
measure: Changes in active commuting (classic or electric bike, public transport, walk, carpooling) from the baseline and one year and a half after the end of the intervention (Month 24)
timeFrame: Baseline, and two years after the baseline (Month 24)
measure: Changes in minutes of moderate-to-vigorous physical activity (MVPA) from the baseline and and the beginning of the intervention (one month after the beginning of the intervention, Month 1)
timeFrame: Baseline and one month and a half after the baseline (Month 1)
measure: Changes in minutes of moderate-to-vigorous physical activity (MVPA) from the baseline and the half of the intervention (Month 3)
timeFrame: Baseline, and three months after the baseline (Month 3)
measure: Changes in minutes of moderate-to-vigorous physical activity (MVPA) from the baseline and the end of the intervention (Month 7)
timeFrame: Baseline, and seven month after the baseline (Month 7)
measure: Changes in minutes of moderate-to-vigorous physical activity (MVPA) from the baseline and two months after the end of the intervention (Month 9)
timeFrame: Baseline, and nine months after the baseline (Month 9)
measure: Changes in minutes of moderate-to-vigorous physical activity (MVPA) from the baseline and six months after the end of the intervention (Month 12)
timeFrame: Baseline, and one year after the baseline (Month 12)
measure: Changes in minutes of moderate-to-vigorous physical activity (MVPA) from the baseline and one year after the end of the intervention (Month 18)
timeFrame: Baseline, and one year and a half after the baseline (Month 18)
measure: Changes in minutes of moderate-to-vigorous physical activity (MVPA) from the baseline and one year and a half after the end of the intervention (Month 24)
timeFrame: Baseline, and two years after the baseline (Month 24)
measure: Changes in exposure to air quality from the baseline and the end of the intervention (Month 7)
timeFrame: Baseline, and seven month after the baseline (Month 7)
measure: Changes in exposure to air quality from the baseline and one year after the end of the intervention (Month 18)
timeFrame: Baseline, and one year and a half after the baseline (Month 18)
measure: Changes in self-reported quality of life from the baseline and the half of the intervention (Month 3)
timeFrame: Baseline, and three months after the baseline (Month 3)
measure: Changes in self-reported quality of life from the baseline and the end of the intervention (Month 7)
timeFrame: Baseline, and seven month after the baseline (Month 7)
measure: Changes in self-reported quality of life from the baseline and six months after the end of the intervention (Month 12)
timeFrame: Baseline, and one year after the baseline (Month 12)
measure: Changes in self-reported quality of life from the baseline and one year and a half after the end of the intervention (Month 24)
timeFrame: Baseline, and two years after the baseline (Month 24)
measure: Changes in self-reported biometrics from the baseline and and the beginning of the intervention (one month after the beginning of the intervention, Month 1)
timeFrame: Baseline and one month and a half after the baseline (Month 1)
measure: Changes in self-reported biometrics from the baseline and the half of the intervention (Month 3)
timeFrame: Baseline, and three months after the baseline (Month 3)
measure: Changes in self-reported biometrics from the baseline and the end of the intervention (Month 7)
timeFrame: Baseline, and seven month after the baseline (Month 7)
measure: Changes in self-reported biometrics from the baseline and one year after the end of the intervention (Month 18)
timeFrame: Baseline, and one year and a half after the baseline (Month 18)
measure: Motivational stage from the baseline and the end of the intervention (Month 7)
timeFrame: Baseline, and seven month after the baseline (Month 7)
measure: Motivational stage from the baseline and six months after the end of the intervention (Month 12)
timeFrame: Baseline, and one year after the baseline (Month 12)
measure: Motivational stage from the baseline and one year after the end of the intervention (Month 18)
timeFrame: Baseline, and one year and a half after the baseline (Month 18)
measure: Motivational stage from the baseline and one year and a half after the end of the intervention (Month 24)
timeFrame: Baseline, and two years after the baseline (Month 24)
measure: Green self-identity from the baseline and the end of the intervention (Month 7)
timeFrame: Baseline, and seven month after the baseline (Month 7)
measure: Green self-identity from the baseline and six months after the end of the intervention (Month 12)
timeFrame: Baseline, and one year after the baseline (Month 12)
measure: Green self-identity from the baseline and one year after the end of the intervention (Month 18)
timeFrame: Baseline, and one year and a half after the baseline (Month 18)
measure: Green self-identity from the baseline and one year and a half after the end of the intervention (Month 24)
timeFrame: Baseline, and two years after the baseline (Month 24)
measure: Changes in habits of alternative modes to the car and car use from the baseline and and the beginning of the intervention (one month after the beginning of the intervention, Month 1)
timeFrame: Baseline and one month and a half after the baseline (Month 1)
measure: Changes in habits of alternative modes to the car and car use from the baseline and the half of the intervention (Month 3)
timeFrame: Baseline, and three months after the baseline (Month 3)
measure: Changes in habits of alternative modes to the car and car use from the baseline and the end of the intervention (Month 7)
timeFrame: Baseline, and seven month after the baseline (Month 7)
measure: Changes in habits of alternative modes to the car and car use from the baseline and two months after the end of the intervention (Month 9)
timeFrame: Baseline, and nine months after the baseline (Month 9)
measure: Changes in habits of alternative modes to the car and car use from the baseline and six months after the end of the intervention (Month 12)
timeFrame: Baseline, and one year after the baseline (Month 12)
measure: Changes in habits of alternative modes to the car and car use from the baseline and one year after the end of the intervention (Month 18)
timeFrame: Baseline, and one year and a half after the baseline (Month 18)
measure: Changes in habits of alternative modes to the car and car use from the baseline and one year and a half after the end of the intervention (Month 24)
timeFrame: Baseline, and two years after the baseline (Month 24)
measure: Changes in intention toward alternative modes to the car and car use from the baseline and and the beginning of the intervention (one month after the beginning of the intervention, Month 1)
timeFrame: Baseline and one month and a half after the baseline (Month 1)
measure: Changes in intention toward alternative modes to the car and car use from the baseline and the half of the intervention (Month 3)
timeFrame: Baseline, and three months after the baseline (Month 3)
measure: Changes in intention toward alternative modes to the car and car use from the baseline and the end of the intervention (Month 7)
timeFrame: Baseline, and seven month after the baseline (Month 7)
measure: Changes in intention toward alternative modes to the car and car use from the baseline and two months after the end of the intervention (Month 9)
timeFrame: Baseline, and nine months after the baseline (Month 9)
measure: Changes in intention toward alternative modes to the car and car use from the baseline and six months after the end of the intervention (Month 12)
timeFrame: Baseline, and one year after the baseline (Month 12)
measure: Changes in intention toward alternative modes to the car and car use from the baseline and one year after the end of the intervention (Month 18)
timeFrame: Baseline, and one year and a half after the baseline (Month 18)
measure: Changes in intention toward alternative modes to the car and car use from the baseline and one year and a half after the end of the intervention (Month 24)
timeFrame: Baseline, and two years after the baseline (Month 24)
measure: Changes in self-efficacy for alternative modes and for the car from the baseline and and the beginning of the intervention (one month after the beginning of the intervention, Month 1)
timeFrame: Baseline and one month and a half after the baseline (Month 1)
measure: Changes in self-efficacy for alternative modes and for the car from the baseline and the half of the intervention (Month 3)
timeFrame: Baseline, and three months after the baseline (Month 3)
measure: Changes in self-efficacy for alternative modes and for the car from the baseline and the end of the intervention (Month 7)
timeFrame: Baseline, and seven month after the baseline (Month 7)
measure: Changes in self-efficacy for alternative modes and for the car from the baseline and two months after the end of the intervention (Month 9)
timeFrame: Baseline, and nine months after the baseline (Month 9)
measure: Changes in self-efficacy for alternative modes and for the car from the baseline and six months after the end of the intervention (Month 12)
timeFrame: Baseline, and one year after the baseline (Month 12)
measure: Changes in self-efficacy for alternative modes and for the car from the baseline and one year after the end of the intervention (Month 18)
timeFrame: Baseline, and one year and a half after the baseline (Month 18)
measure: Changes in self-efficacy for alternative modes and for the car from the baseline and one year and a half after the end of the intervention (Month 24)
timeFrame: Baseline, and two years after the baseline (Month 24)
measure: Changes in intention implementation from the baseline and and the beginning of the intervention (one month after the beginning of the intervention, Month 1)
timeFrame: Baseline and one month and a half after the baseline (Month 1)
measure: Changes in intention implementation from the baseline and the half of the intervention (Month 3)
timeFrame: Baseline, and three months after the baseline (Month 3)
measure: Changes in intention implementation from the baseline and the end of the intervention (Month 7)
timeFrame: Baseline, and seven month after the baseline (Month 7)
measure: Changes in intention implementation from the baseline and two months after the end of the intervention (Month 9)
timeFrame: aseline, and nine months after the baseline (Month 9)
measure: Changes in intention implementation from the baseline and six months after the end of the intervention (Month 12)
timeFrame: Baseline, and one year after the baseline (Month 12)
measure: Changes in intention implementation from the baseline and one year after the end of the intervention (Month 18)
timeFrame: Baseline, and one year and a half after the baseline (Month 18)
measure: Changes in intention implementation from the baseline and one year and a half after the end of the intervention (Month 24)
timeFrame: Baseline, and two years after the baseline (Month 24)
measure: Changes in attitudes toward alternative modes to the car and toward car use from the baseline and and the beginning of the intervention (one month after the beginning of the intervention, Month 1)
timeFrame: Baseline and one month and a half after the baseline (Month 1)
measure: Changes in attitudes toward alternative modes to the car and toward car use from the baseline and the half of the intervention (Month 3)
timeFrame: Baseline, and three months after the baseline (Month 3)
measure: Changes in attitudes toward alternative modes to the car and toward car use from the baseline and the end of the intervention (Month 7)
timeFrame: Baseline, and seven month after the baseline (Month 7)
measure: Changes in attitudes toward alternative modes to the car and toward car use from the baseline and two months after the end of the intervention (Month 9)
timeFrame: Baseline, and nine months after the baseline (Month 9)
measure: Changes in attitudes toward alternative modes to the car and toward car use from the baseline and six months after the end of the intervention (Month 12)
timeFrame: Baseline, and one year after the baseline (Month 12)
measure: Changes in attitudes toward alternative modes to the car and toward car use from the baseline and one year after the end of the intervention (Month 18)
timeFrame: Baseline, and one year and a half after the baseline (Month 18)
measure: Changes in attitudes toward alternative modes to the car and toward car use from the baseline and one year and a half after the end of the intervention (Month 24)
timeFrame: Baseline, and two years after the baseline (Month 24)
measure: Changes in perceived susceptibility and perceived severity of getting coronavirus disease from the baseline and and the beginning of the intervention (one month after the beginning of the intervention, Month 1)
timeFrame: Baseline and one month and a half after the baseline (Month 1)
measure: Changes in perceived susceptibility and perceived severity of getting coronavirus disease from the baseline and the half of the intervention (Month 3)
timeFrame: Baseline, and three months after the baseline (Month 3)
measure: Changes in perceived susceptibility and perceived severity of getting coronavirus disease from the baseline and the end of the intervention (Month 7)
timeFrame: Baseline, and seven month after the baseline (Month 7)
measure: Changes in perceived susceptibility and perceived severity of getting coronavirus disease from the baseline and two months after the end of the intervention (Month 9)
timeFrame: Baseline, and nine months after the baseline (Month 9)
measure: Changes in perceived susceptibility and perceived severity of getting coronavirus disease from the baseline and six months after the end of the intervention (Month 12)
timeFrame: Baseline, and one year after the baseline (Month 12)
measure: Changes in perceived susceptibility and perceived severity of getting coronavirus disease from the baseline and one year after the end of the intervention (Month 18)
timeFrame: Baseline, and one year and a half after the baseline (Month 18)
measure: Changes in perceived susceptibility and perceived severity of getting coronavirus diseasefrom the baseline and one year and a half after the end of the intervention (Month 24)
timeFrame: Baseline, and two years after the baseline (Month 24)
measure: Changes in subjective norms toward alternative modes to the car and car use from the baseline and and the beginning of the intervention (one month after the beginning of the intervention, Month 1)
timeFrame: Baseline and one month and a half after the baseline (Month 1)
measure: Changes in subjective norms toward alternative modes to the car and car use from the baseline and the half of the intervention (Month 3)
timeFrame: Baseline, and three months after the baseline (Month 3)
measure: Changes in subjective norms toward alternative modes to the car and car use from the baseline and the end of the intervention (Month 7)
timeFrame: Baseline, and seven month after the baseline (Month 7)
measure: Changes in subjective norms toward alternative modes to the car and car use from the baseline and two months after the end of the intervention (Month 9)
timeFrame: aseline, and nine months after the baseline (Month 9)
measure: Changes in subjective norms toward alternative modes to the car and car use from the baseline and six months after the end of the intervention (Month 12)
timeFrame: Baseline, and one year after the baseline (Month 12)
measure: Changes in subjective norms toward alternative modes to the car and car use from the baseline and one year after the end of the intervention (Month 18)
timeFrame: Baseline, and one year and a half after the baseline (Month 18)
measure: Changes in subjective norms toward alternative modes to the car and car use from the baseline and one year and a half after the end of the intervention (Month 24)
timeFrame: Baseline, and two years after the baseline (Month 24)
measure: Changes in carbon footprint associated to transport
timeFrame: To be defined
Other outcomes:
measure: Reach of the intervention
timeFrame: During the recruitment and enrollement, an average of 2 years
measure: Quality of the implementation
timeFrame: During the implementation of the intervention, an average of 2 years
measure: Travel satisfaction
timeFrame: Baseline
measure: Autonomous and controlled motivation for alternative modes to the car
timeFrame: Month 0
measure: Accessibility and fluidity according to transport modes
timeFrame: Baseline
measure: Self-control ressources
timeFrame: Baseline
measure: Self-control ressources
timeFrame: One month and a half after the baseline (Month 1)
measure: Self-control ressources
timeFrame: Three months after the baseline (Month 3)
measure: Self-control ressources
timeFrame: Seven months after the baseline (Month 7)
measure: Self-control ressources
timeFrame: Nine months after the baseline (Month 9)
measure: Self-control ressources
timeFrame: One year after the baseline (Month 12)
measure: Self-control ressources
timeFrame: One year and a half after the baseline (Month 18)
measure: Self-control ressources
timeFrame: Two years after the baseline (Month 24)
Locations:
city: Saint-Martin-d'Hères
country: France
facility: Univ. Grenoble-Alpes
state: Rhône-Alpes
Study officials:
affiliation: Laboratoire SENS, Univ. Grenoble-Alpes
name: Aïna Chalabaev, Professor
role: STUDY_DIRECTOR
References:
citation: Teran-Escobar C, Duche S, Bouscasse H, Isoard-Gatheur S, Juen P, Lacoste L, Lyon-Caen S, Mathy S, Ployon E, Risch A, Sarrazin P, Slama R, Tabaka K, Treibich C, Chardonnel S, Chalabaev A. InterMob: a 24-month randomised controlled trial comparing the effectiveness of an intervention including behavioural change techniques and free transport versus an intervention including air pollution awareness-raising on car use reduction among regular car users living in Grenoble, France. BMC Public Health. 2022 Sep 16;22(1):1763. doi: 10.1186/s12889-022-14099-4.