Scoped answer: the supplied evidence supports running a bounded local randomized test among consenting adults; it does not support permanent rollout or a promised effect size. Confidence is moderate because one sizable randomized urban study estimates a positive collection effect, while local evidence establishes feasibility but not causation.
Convergence: F1/C estimates a 5-percentage-point difference, with interval 1-9. Its point estimate exceeds the 3-point planning threshold, but the interval includes smaller effects. F2/A has a compatible 7-point descriptive difference and supplies local operational signals. Do not average 5 and 7: designs and comparisons differ. F3/E suggests acceptability and channel choice matter, but the engaged volunteer sample cannot estimate prevalence. F4/D is context only, not effect evidence. F5/C does not show a clear late-fee effect; its interval includes modest harm and benefit, so “no effect” would be wrong.
Limits and alternatives: transfer from four urban libraries is uncertain; both intervention findings omit or underrepresent adults without mobile access; local period/season changes could explain F2; message timing or participant engagement could contribute. Peer-review status is unknown. The evidence says little about children, rural patrons, permanent behavior, or equitable channel access.
Can decide now: authorize design of a four-week test with consent, random allocation, pre-defined collection outcome, channel/accessibility review, opt-out/late-message/staff-time guardrails, and stop thresholds. Can test now: whether the local effect clears 3 points without unacceptable guardrail cost and whether channel choice is needed. Cannot conclude: reminders caused the local pilot difference, reduce late fees, work for patrons without mobile numbers, or merit rollout. Change condition: a corrected F1 null estimate, infeasible local operations, or unacceptable opt-out/access disparity would weaken the recommendation; a well-run local test clearing threshold with stable guardrails would strengthen it. Ledger: conclusion effect→F1/F2; feasibility→F2; acceptability→F2/F3; limits→F1-F5.