Fig. 1: A large jump in zoster vaccine receipt at the date-of-birth eligibility threshold.

a–f, The date-of-birth eligibility cut-off led to a large discontinuity in zoster vaccine receipt (a), but there is baseline exchangeability across the cut-off for uptake of other preventive interventions (flu vaccine (d), pneumococcal polysaccharide vaccine (PPV) (e) and statin medications (f)) as well as past shingles (b) and dementia (c) diagnoses. The data source for this analysis was the SAIL database for Wales. All analyses were run on the same sample as those for the effect of the zoster vaccine on dementia occurrence. The exception is c, for which we did not exclude individuals with a diagnosis of dementia before the start of the zoster vaccine program. The grey dots show the mean value for each 10-week increment in week of birth. The grey shading of the dots is proportionate to the weight that observations from this 10-week increment received in the analysis.