Improving the timeliness and equity of preschool childhood vaccinations: Mixed methods evaluation of a quality improvement programme in primary care.

BACKGROUND

We conducted a mixed methods evaluation to assess whether implementing a primary care quality improvement (QI) programme utilising a digital call-and-recall tool improved timely receipt and equity of first measles, mumps and rubella (MMR) and diphtheria tetanus, pertussis and polio-containing (DTaP /IPV) vaccinations.

METHODS

138,133 and 136,952 children were eligible to receive first MMR and DTaP/IPV respectively between 1st January 2019 and 31st January 2024 in North East London. We compared proportions with timely first MMR or DTaP/IPV receipt (by ages 18 and six months respectively) pre- and post-implementation using an interrupted time series analysis. We calculated change in the Slope Index of Inequality (SII) by an area-level deprivation measure. We conducted 'Think Aloud' exercises and semi-structured interviews with users.

FINDINGS

The proportion of children with timely first MMR receipt increased by 5·3 % (Rate Ratio [RR]:1·053, 95 % confidence interval [CI]:1·033-1·073), equating to an absolute increase in timely MMR receipt of 4·1 % - from 77·7 % to 81·8 % - and for first DTaP/IPV by 0·9 % (RR:1·009, 95 % CI:1·003-1·015). There was no significant change in SII for either vaccine. Users reported improved recall with tool use, but identified practice-level and systemic barriers, including staff dynamics and unachievable national targets, limiting its consistent use.

INTERPRETATION

In a real-world setting, a call-and-recall tool within a primary care QI programme improved timely first MMR receipt. Sustained improvement requires additional support including by incentivising achievable targets and improving staff capacity and training.

FUNDING

National Institute of Health and Care Research; Barts Charity.