Research paper · RP32

Warm Wishes, Measured

Zeng’s 2015 review asked whether loving-kindness practice lifts positive emotion. This update asks a sharper question for people who work: after another decade of trials, what happens to connection, compassion and stress? In working adults the best available random-effects estimates are Hedges g = 0.38 for interpersonal connection (12 employee samples) and g = 0.54 for stress (10 employee samples). Both figures come from Wang and colleagues’ workplace synthesis, which closed in March 2022 and remains the most defensible pooled number for employed samples. Trials published since then, including a 2025 four-week, three-minute-a-day video programme in full-time employees, point the same way against no-practice controls and shrink against active practices such as light exercise or mindfulness. Compassion against passive controls in Petrovic and colleagues’ 2024 adult review was small and significant (g = 0.36, three trials). Dose in minutes and weeks did not reliably change the size of the effect. Live teachers were not required. Audio and short video were enough. Certainty is moderate for workplace stress and interpersonal outcomes, lower for positive affect against active controls, and very low for Indian professionals: no randomised trial of this practice was found on CTRI, PubMed or Google Scholar through September 2026. A null against another active practice is a real result, not a failed study. For an Indian workplace programme the honest offer is a short daily warm-wishes rep, counted, with a human hand-off when the number is not the point.