Abstract
INTRODUCTION: The LIFE-ID (lifestyle interventions for adults with intellectual disabilities) intervention, a multicomponent and multilevel lifestyle programme, was developed to improve the lifestyle of adults with ID and the support provided by their interpersonal and organisational environment. This paper describes the protocol of a multiple baseline one-arm feasibility and effectiveness study of the LIFE-ID intervention. METHOD AND ANALYSIS: To evaluate the effectiveness of the LIFE-ID intervention for adults with ID, alongside an embedded assessment of feasibility, we employ a one-arm multiple-baseline trial in the Netherlands, in collaboration with healthcare organisations providing support to adults with ID. The LIFE-ID intervention intervenes at intrapersonal, interpersonal and organisational levels and uses a tailored approach to improve both physical activity and dietary quality in adults with ID. To support healthcare professionals in selecting interventions, the lifestyle support tool was developed, including existing, effective, and ID-specific nutrition and physical activity interventions. The lifestyle support tool takes into account intrapersonal, interpersonal and organisational characteristics and considers the participants' wishes and needs related to their personal lifestyle goals. An embedded feasibility evaluation of the LIFE-ID intervention is conducted with the first 15 participants in the study and their involved healthcare professionals. Information on dose delivered, dose received, acceptability and fidelity of the intervention performance compared with the description is retrieved through biweekly reflection forms obtained from direct support professionals. Group interviews are conducted to collect feedback on the experiences with the LIFE-ID intervention discussing the following topics: acceptance and suitability of the intervention, and barriers and facilitators during execution. Outcomes related to the lifestyle support tool include usability, usefulness and ease of use. To evaluate the effectiveness of the 6-month LIFE-ID intervention, 80 adults (≥18 years) with ID are included (including 15 participants from the feasibility evaluation). The primary outcome is physical activity. Secondary outcomes on the intrapersonal level include dietary quality, physical fitness, body composition, calf circumference, blood pressure, heart rate, frailty, anxiety, depression, behavioural problems and goal attainment. On the interpersonal level, outcomes include attitude of professionals towards support in healthy exercise and nutrition. On the organisational level, outcomes are barriers and facilitators associated with creating a healthy living environment, and determinants that affect the implementation of the LIFE-ID intervention. ETHICS AND DISSEMINATION: The study protocol is approved by the Medical Ethics Review Board of the University Medical Center Groningen (METc 2023-520). Written consent is obtained from all participants who are capable to provide consent, and from legal representatives when they are not. Study findings will be disseminated through peer-reviewed publications, conference presentations and accessible summaries for participants, families and healthcare organisations. TRIAL REGISTRATION NUMBER: The study has been registered in the Overview of Medical Research in the Netherlands (OMON; NL85438), which is linked to the International Clinical Trial Registry Platform (ICTRP).