Table 1.

Community data source identification and description.

Data source and description			Identification and use of the relevant terms
Regional or municipal
	211 Grand Montréal [99]: web-based and phone service aiming to connect citizens to community organizations and services within Greater Montréal. The database contains detailed contact, location, and services information about public, para-public, and community organizations that may serve the “senior” population.	The database was filtered for “seniors,” “Montréal” location, and “English” as the service language. The output included a list of subcategories containing pertinent community organizations, of which some overlapped across subcategory offering a broad range of services. The organizations with service descriptions relevant to reducing loneliness or social isolation were identified, and keywords were extracted from these descriptions and keyword tags.
	Données Montréal [100]: open-access data to services and events provided by the city of Montréal and offered within the Montréal area, several of which have the potential to improve mental well-being. Données Montréal data sets are not necessarily specific to older adults, and they do not explicitly state interventions or services to reduce loneliness and isolation.	Nine data sets were extracted from Données Montréal owing to their potential for providing information on infrastructure aimed at reducing loneliness and isolation in Montréal. Only databases that offered information regarding ≥1 intervention types were extracted. Four of these data sets were relevant, providing information on cultural activities, lists of parks, seasonal recreational activities, and museums, libraries, or recreational activities in Montréal. The data sets were reported in French and were translated into English for the extraction. Each data set varied with respect to how the information or events were reported. For example, some provided geolocations, time, and events, whereas others offered description of events. Keywords relating to events or places that one could visit for reducing loneliness and social isolation were extracted. None of the events and places were specific to older adults but were evidently accessible to them and were primarily related to recreational activities.
Neighborhood-specific resources
	Centraide of Greater Montréal [101]: directory of community agencies in Montréal, as separated by boroughs, that receive financial support from the Centraide of Greater Montréal Foundation. Centraide aims to reduce poverty and exclusion in the city of Montréal and funds community organizations to achieve this objective. Two specific neighborhoods or boroughs in Montréal were investigated, Côte-des-Neiges and Notre-Dame-de-Grace, where organizations serving older individuals with services relevant for reducing loneliness and social isolation were included.	The directory of supported agencies and projects were searched on the Centraide website. The 2 target boroughs were searched for through the filter “Territory served,” providing a list of organizations that Centraide supports specific to these regions. Each organization had a list of activities offered, where activities that compared with those identified in the meta-review for reducing loneliness and isolation and accessible to older adults were extracted.
	Community outreach worker: a comprehensive list of community organizations available in the region of Notre-Dame-de-Grace, as collected by a community outreach worker for the same period. Several organizations offer services aimed at reducing loneliness and social isolation and supporting older adults in the community.	The database was obtained from the community outreach worker, and relevant organization services were identified that reflected the meta-review intervention types. Keywords were extracted from the service descriptions, as formulated by the outreach worker.
Population-specific resources (older adults)
	Contactivity Centre [102]: a community center (nonprofit) serving older adults in Montréal that offers resources, referrals, and activities to improve the mental, emotional, and physical well-being of its members. It maintains a large database of organizations that offer a variety of services.	The “Resource and referrals” page of the Contactivity Centre website provides categories of services offered, listing community organizations and the corresponding websites that can provide access to those services. The relevant categories identified included “Recreational and Community Services,” “Friendly Visits,” “Daily Phone Calls,” and “Senior Advocacy.” Under each category, the listed organization websites were searched, and keywords were extracted from the services that compared with those identified in the meta-review.
	AMI-Québec [103]: a nonprofit organization providing access to courses, workshops, interest groups, activities, and services in person or on the web as well as a database of external community organizations providing comparable services for the older adult population. Some of the external organizations are specific to older adults and offer services to reduce loneliness and social isolation.	The “Resource List” on the AMI-Québec website included a “Special Populations” category and a “Seniors” subcategory, which listed relevant community organizations with a short description of services offered. These lists were searched and relevant keywords were extracted from the services descriptions.
	FADOQa [104]: The largest older adult organization in Canada, whereby membership provides access to hundreds of clubs and programs designed for older adults.	FADOQ is a network of older adult clubs and groups promoting active and healthy aging. They offer programs and activities related to recreational, physical, and ICTb intervention types through their clubs. Information available from their website was mostly about individual clubs, web-based resources, and provincial older adult events.
	RIAQc [105]: a nonprofit Québec Seniors Information Network, run by older adults, to offer members knowledge resources, workshops, and services related to information technology, health, and travel.	RIAQ is an information network for older adults and offers workshop in technology-related fields, which were identified as relevant for reducing loneliness and isolation through the ICT intervention type.

^aFADOQ: Réseau Fédération de l’âge d’or du Québec.

^bICT: information and communication technology.

^cRIAQ: Réseau d’information des aînés du Québec.