Table 1.

Strengths of the evidence, challenges posed by gaps, and consequent priority needs in research on social connection

Strengths of evidence	Challenges	Priority needs
Converging evidence across scientific disciplines	Variability in conceptualization and measurement	A multi‐factorial approach is needed.
Many validated assessment tools	Variability in assessment tools limits comparisons across time, or different samples. Validated instruments may not be generalizable to other cultures, settings, and contemporary modes of socializing.	Consistency of assessment to establish prevalence rates and track trends. Improve or create new measures that are valid, reliable and acceptable.
Dose‐response of social connection across the lifespan	Most research and attention are on extreme risk and older adults.	A focus across the risk trajectory (including prevention) and across ages is needed.
Converging evidence across social connection components	Fewer studies examine multiple components in the same sample.	Further evidence of potential independent, additive and synergistic effects is needed to assess risk more precisely. Further evidence is needed on how each factor may differentially influence different kinds of outcomes.
Evidence on mortality is consistent across causes of death, country of origin, gender, and health status	Fewer studies include or differentiate: comprehensive health outcomes, low‐ and middle‐income countries, marginalized groups, varying modalities of socializing (e.g., in‐person, remote, non‐human).	Basic research to fill these gaps is needed.
Robust evidence of mortality and objective health consequences	Weaker and mixed evidence on effective strategies to mitigate risk (weaker methodologies were employed; most interventions are individually focused; most interventions are targeted at those most severely affected). Less is known about other non‐health outcomes.	Evidence‐based solutions: rigorous evaluations allowing for strong inference; interventions across the socio‐ecological model; prevention and mitigation of risk earlier on in the risk trajectory. Evidence on more diverse outcomes (e.g., economic, civic engagement, education, incarceration).