Complete description and application :…


Just-in-time adaptive interventions (JITAIs) are a category of sophisticated, personalized digital interventions that aim to deliver the right pharmacologic or non-pharmacologic intervention component, at the right time, based on the individual’s changing state.1 To achieve this, JITAIs rely on devices that collect continuous or high-frequency data about the individual and his/her environment (e.g., wearable glucose sensor, smartphone accelerometer), and they use this information to select the appropriate type and amount of intervention and deliver it in real-time, often by using sophisticated data analytics such as reinforcement learning.2,3

The revolutionary innovation of JITAIs lies in their ability to deliver interventions outside of consultations, in real-life settings (e.g., at home, at work) where health behavior and disease self-management take place, and where individuals are unaccompanied by a health care professional. Moreover, to maximize efficacy and reduce waste, JITAIs deliver interventions at the precise moment when these are needed, and only the individual is able to receive them. These unique features have led to the increasing popularity of JITAIs across health domains, from semi-automating diabetes self-management,3 to supporting the increase of physical activity.2

To be effective and usable in real-life settings, JITAIs must be minimally disruptive to the individual. Receiving an intervention at an inopportune moment can lead to non-adherence and irritation (e.g., receiving notifications to go for a walk during a meeting), and even impact the privacy, safety or well-being of the individual (e.g., receiving a message regarding alcohol misuse when surrounded by coworkers). Indeed, non-adherence and drop-out are major challenges in the scale-up of personalized digital interventions, often associated with the perception of these interventions as an intrusive hassle.3 These concerns are paramount for the integration of JITAI interventions in the care of chronically ill patients, who often experience considerable burden associated with their treatment. In spite of the benefits of JITAIs at improving health outcomes, patients may be unwilling to adopt a JITAI perceived as burdensome or intrusive. However, there are no studies that examine which JITAI modalities are acceptable to whom, and in which circumstances.

So far, the literature on JITAIs has been synthesized in a fragmented manner, in systematic reviews focusing on specific behaviors.2 An overview mapping the JITAI literature across behaviors and diseases would help us examine intervention characteristics specific to JITAIs, assess their readiness for clinical deployment at scale, and identify research gaps. Additionally, assessing patient acceptability of using JITAIs as part of usual care, and its association with specific JITAI modalities, can inform JITAI implementation and help us optimize future JITAI development.


A systematic review of JITAIs assessed in RCTs.

Aim: This project will map all JITAIs assessed in published RCTs with a focus on aspects relevant to clinical deployment and patient/user engagement.


Literature search and study selection: The literature search and study selection of RCTs assessing JITAIs is currently being performed for an ongoing project at our research team, focused on characteristics of RCTs assessing JITAIs. The database of included studies can easily be updated for the envisioned review using the same search strategy. Study selection will be performed independently by 2 reviewers.

Data extraction: Data extraction will be performed independently by 2 reviewers and it will focus on characteristics specific to the clinical deployment of JITAIs (e.g., conditions and behaviors that JITAIs have been tested for, clinically relevant outcomes), and patient/user engagement (e.g., intervention development strategies used to maximize engagement and acceptability and minimize burden/intrusiveness).

Data analysis: JITAI characteristics will be summarized using descriptive statistics. Important characteristics (e.g., monitoring tools, intervention components, techniques to increase engagement and acceptability) will be tabulated with clinical domains (diseases, behaviors), to enable the identification of gaps and potential cross-domain knowledge transfer in the entire JITAI RCT literature.

An international vignette-based survey of patient acceptability of JITAIs.

Aim: This study will evaluate the association between specific JITAI characteristics and patients’ stated acceptability of the JITAI.


Vignette-based studies are a robust research design used to identify stated preference and have been validated against real-world behavior.4 We have previously used vignettes to identify patient perceptions of digital intervention characteristics.5

Survey development: We will develop vignettes (i.e., hypothetical scenarios) describing JITAIs. Participants will assess their acceptability of JITAIs presented in the vignettes. The vignettes will include JITAI characteristics likely to affect acceptability based on the findings of project 1.

Data collection: Recruitment will be performed internationally by: 1) inviting members of the ComPaRe e-cohort (, 2) leveraging our international network of collaborators in different fields (e.g., endocrinologist Pr. Montori [Mayo Clinic, USA], psychiatrist Pr. Cipriani [Oxford University, UK]) to disseminate the study, and 3) through collaboration with online media and patient social-media groups. We have previously successfully used this strategy to recruit >1,000 participants in a few months.5

Data analysis and sample size: The unit of analysis is the vignette-assessment. The primary analysis will use multi-level models, accounting for clustering (i.e., >1 vignette assessed per participant), to examine the association between acceptability, and the following predictors: JITAI characteristics (vignette factor-levels) and participant characteristics. We will collect at least 10 vignette-assessments per predictor.

Projected output

The aforementioned projects will be reported in two published articles:

  • A systematic mapping review of studies assessing JITAIs.
  • An international vignette-based survey of patient acceptability of JITAIs.

Projected timeframe

  • Semester 1: Update of dataset for review. Data extraction.
  • Semester 2: Data analysis for project 1. Write-up of first article.
  • Semester 3: Development of vignette-based survey for project 2. Survey launch and recruitment.
  • Semester 4: Complete recruitment. Data analysis for project 2.
  • Semesters 5 and 6: Write-up of second article. Thesis write-up and defense.


  1. Nahum-Shani I, Smith SN, Spring BJ, et al. Just-in-Time Adaptive Interventions (JITAIs) in Mobile Health: Key Components and Design Principles for Ongoing Health Behavior Support. Ann Behav Med. 2018;52(6):446-462. doi:10.1007/s12160-016-9830-8
  2. Hardeman W, Houghton J, Lane K, Jones A, Naughton F. A systematic review of just-in-time adaptive interventions (JITAIs) to promote physical activity. Int J Behav Nutr Phys Act. 2019;16(1):31. doi:10.1186/s12966-019-0792-7
  3. Ramchandani N, Arya S, Ten S, Bhandari S. Real-life utilization of real-time continuous glucose monitoring: the complete picture. J Diabetes Sci Technol. 2011;5(4):860-870. doi:10.1177/193229681100500407
  4. Atzmüller C, Steiner PM. Experimental vignette studies in survey research. Methodology: European Journal of Research Methods for the Behavioral and Social Sciences. 2010;6(3):128-138. doi:10.1027/1614-2241/a000014
  5. Oikonomidi T, Ravaud P, Cosson E, Montori V, Tran V-T. Evaluation of Patient Willingness to Adopt Remote Digital Monitoring for Diabetes Management. JAMA network open. 2021;4(1):e2033115. doi:10.1001/jamanetworkopen.2020.33115