Abstract: Objective To develop a scale assessing cognition and intention regarding group voluntary blood donation, and evaluate its reliability and validity. Methods A theoretical framework was constructed based on group dynamics. Initial scale items were generated through literature review and semi-structured interviews, and then revised and optimized via a pilot test. A total of 1 052 participants were recruited from enterprises and institutions that had regularly organized group blood donation activities, and they completed the formal scale administration. Item analysis done using the total sample. Then, all participants were randomly assigned into two subsamples: Sample 1 (n1=526) for exploratory factor analysis, and Sample 2 (n2=526) for confirmatory factor analysis, as well as tests of convergent validity, discriminant validity and reliability. Results The final scale comprised 27 items loading onto six factors: social cohesion, task cohesion, self-monitoring, conformity, self-efficacy, and group blood donation intention. These six factors collectively explained 78.91% of the total variance, exhibiting good construct validity. The fit indices of the six-factor structure were as follows: χ²/df=3.65, CFI=0.911, TLI=0.899, RMSEA=0.071, SRMR=0.065. The scale also showed favorable convergent and discriminant validity. The overall Cronbach's α coefficient and the Cronbach's α coefficients for each of the six dimensions were all≥0.8, reflecting strong internal consistency reliability. Conclusion The Group Voluntary Blood Donation Cognition and Intention Scale exhibits satisfactory reliability and validity, and could be used to evaluate members' cognitive perceptions and donation intentions in the context of group blood donation.

Key words: Group voluntary blood donation, Group dynamics, Scale development, Validity, Reliability