Hypothesis
Traditional media such as books would raise well-being while newer media would not, with effects visible when a person changes their own media use from week to week.
What failed
In a six-week longitudinal panel representative of UK adults aged 16 and over (N = 2,159), effects of media use on well-being were generally small. They showed up mostly between people rather than within the same person over time, for using versus not using a medium rather than for time spent, and for mood rather than life satisfaction.
Broken assumption
Which kind of media a person uses meaningfully changes how well they feel.
Why
The abstract reports the pattern without a single explanation; the common contrast between 'good' old media and 'bad' new media was not borne out.
From the published paper: Johannes et al. Scientific Reports, 2022. ↗CC BY