Abstract Background DOLCE (Improving Decision making On Location of Care with the frail Elderly and their caregivers) was a post-intervention clustered randomised trial (cRT) to assess the effect of training home care teams on interprofessional shared decision-making (IP-SDM). Alongside the cRT, we sought to monitor healthcare providers’ level of behavioural intention to engage in an IP-SDM approach and to identify factors associated with this intention. Methods We conducted two cross-sectional surveys in the province of Quebec, Canada, one each at cRT entry and exit. Healthcare providers (e.g. nurses, occupational therapists and social workers) in the 16 participating intervention and control sites self-completed an identical paper-based questionnaire at entry and exit. Informed by the Integrated model for explaining healthcare professionals’ clinical behaviour by Godin et al. (2008), we assessed their behavioural intention to engage in IP-SDM to support older adults and caregivers of older adults with cognitive impairment to make health-related housing decisions. We also assessed psychosocial variables underlying their behavioural intention and collected sociodemographic data. We used descriptive statistics and linear mixed models to account for clustering. Results Between 2014 and 2016, 271 healthcare providers participated at study entry and 171 at exit. At entry, median intention level was 6 in a range of 1 (low) to 7 (high) (Interquartile range (IQR): 5–6.5) and factors associated with intention were social influence (β = 0.27, P < 0.0001), beliefs about one’s capabilities (β = 0.43, P < 0.0001), moral norm (β = 0.31, P < 0.0001) and beliefs about consequences (β = 0.21, P < 0.0001). At exit, median intention level was 5.5 (IQR: 4.5–6.5). Factors associated with intention were the same but did not include moral norm. However, at exit new factors were kept in the model: working in rehabilitation (β = − 0.39, P = 0.018) and working as a technician (β = − 0.41, P = 0.069) (compared to as a social worker). Conclusion Intention levels were high but decreased from entry to exit. Factors associated with intention also changed from study entry to study exit. These findings may be explained by the major restructuring of the health and social care system that took place during the 2 years of the study, leading to rapid staff turnover and organisational disturbance in home care teams. Future research should give more attention to contextual factors and design implementation interventions to withstand the disruption of system- and organisational-level disturbances. Trial registration Clinicaltrials.gov (NCT02244359). Registered on September 19th, 2014.