## 2 Materials and Methods
### Critical Appraisal and Overview of Studies Included  
The review adopted the Mixed Methods Appraisal Tool (MMAT) due to its applicability for qualitative, quantitative, and mixed methods studies. Detailed scoring for each paper for each question is available in Supplementary Material Tables S3 and S4. To answer RQ1, the PRISMA workflow resulted in six articles to be critically appraised. Five of the six articles demonstrated medium to high quality as they contained information to fulfil the criteria in MMAT [40; 41; 42; 43; 44]. The sixth article did not offer enough information to help understand the quality of the qualitative method used [45]. Therefore, it was excluded. The five studies [40; 41; 42; 43; 44] included answered the research question by focusing on the acceptability of ambient assistive technologies. They ensured that research methods were appropriate for the research question by referring to methods in precedent studies or theoretical frameworks. They included direct responses and a range of responses to ensure the data were sufficiently substantiated. The discussion for all five studies provided a summary corresponding with the research intent, the data collected, and the analysed results to ensure a coherent, logical presentation of the arguments. One of the studies [43] did not provide the exact research methods or sampling procedure. The results and discussion sessions were not available. The lack of details for critical appraisal excluded this study from further review. The five included studies [40; 41; 42; 43; 44], retrieved from published journals, involved three in-depth interviews, one focus group, and one mixed-method study. The search did not result in grey literature. Four studies investigated more than one type of ambient technology [40; 41; 42; 44]. One of these four focused on alarms [40], encompassing smoke detectors and social and environmental alarms. The other three [41; 42; 44] did not specify a particular type of sensor, with questions based on the impression of general use of sensors, encompassing both remote and wearable sensors. Two of the five articles [41; 43] concerned exploratory research on innovative remote sensing technologies; one of these considered installing a system of sensors to provide comprehensive surveillance throughout a residential home [41], and the other [43] replaced the subject in real-person video monitoring footage with other representations, including cartoons, sticky figures, and silhouettes. In answering RQ2, the searches and screening process resulted in thirteen articles to be critically appraised. Twelve [46; 47; 48; 49; 50; 51; 52; 53; 54; 55; 56; 57] of the thirteen studies demonstrated medium to high quality, as the twelve studies had information to answer all criteria in the MMAT, with the thirteenth [56] study falling short of answering S2 and the rest of the criteria. The research hypothesis of these twelve studies was clear and relevant, focusing on vibration and/or acoustic sensing technologies in monitoring human activities. All showed reliable data collection methods, using experiments or mixed methods to ensure the sampling strategy was appropriate and relevant to the population. Experimental studies [46; 47; 48; 50; 51; 52; 53; 54; 55; 56; 57] involving model development considered relevant parameters to simulate human activity. Those involving sensor development used dummy models, dolls, or human actors for sampling. The only mixed-methods study [49] included a qualitative human focus group study to inform model development using parameters identified. Issues with missing data were not observed for the mixed-method study. Appropriate constructs and statistical analysis were applied to draw evidence-based conclusions. Among the thirteen studies, one did not have information on detailed sampling strategies, or the methods adopted for analysis. Since the information in it was inadequate to determine its quality, the article was exempted from further review [58].