Implementation and evaluation of a collaborative quality improvement program to improve immunization rate and reduce missed opportunities for vaccination in primary health-care facilities: a time series study in Kano, Nigeria.

: The authors aimed to implement a quality improvement (QI) collaborative in primary health care (PHC) facilities in Nassarawa Local Government Area of Kano, Nigeria, to reduce missed opportunities for vaccination (MOV) among children aged 0-23 months. : Plausibility evaluation design was used in this study. Frontline health workers from five purposively selected PHC facilities used divergent-convergent thinking to select change ideas. Change ideas were implemented in two plan-do-study-act cycles that were 4 weeks apart. Statistical process control using P-chart was used to plot the outcomes over time. Upper and lower control limits were calculated for each p-chart. : In the facilities that implemented the QI program, the average percentage of MOV in the pre-implementation period was 31.7% with an upper control limit (UCL) of 44.5% and lower control limit (LCL) of 18.9%. After commencing QI implementation, data points stabilized as all points were within the control limits. Improvement was more evident in PHC 1 and 5. : The findings from this study suggest that frontline health workers are capable of tailoring change ideas to their local context to generate context-specific change ideas. It also showed that QI can be used to attain process control in the occurrence of MOV.