Explaining donor lapse in voluntary blood donation: A grounded theory study from China.

In recent years, many countries and regions have witnessed a decline or lapse in voluntary blood donation, leading to blood shortages and instability in transfusion services. However, little is known about why previously active donors discontinue donating. Drawing on over 230 semi-structured interviews and 5310 social media comments, this study employs grounded theory to construct an explanatory framework of donor lapse. The findings reveal five major drivers: institutional trust gap, cost-benefit imbalance, weakening of social norms, motivational instrumentalisation, and negative donation/use experiences. Based on these results, the study proposes a multidimensional "Push-Pull-Mooring-Trigger (P-P-M-T)" framework: institutional trust gap and weakening of social norms act as push forces driving donors away; perceived cost-benefit imbalance serves as a pull force toward discontinuation; motivational instrumentalisation operates as a key mediating mechanism; and negative donation/use experiences function as proximal triggers that catalyze final withdrawal decisions. This study advances understanding of the psychosocial and institutional mechanisms underlying donor lapse and provides actionable implications for sustaining voluntary blood donation systems.