The Spiritual Transcendence Index (STI; Seidlitz et al., 2002) has eight items (e.g., “My spirituality gives me a feeling of fulfillment,” “I experience a deep communion with God,” “Even when I experience problems, I can find a spiritual peace inside”) that measure subjective experiences of the sacred and their effects on one’s self-perception, feelings, goals, and ability to overcome difficulties. The scale examines how one’s daily experiences are interpreted in terms of spirituality.
Seidlitz, L., Abernathy, A. D., Duberstein, P. R., Evinger, J. S., Chang, T. H., & Lewis, B. L. (2002). Development of the Spiritual Transcendence Index. Journal for the Scientific Study of Religion, 41, 439 – 453. doi: 10.1111/1468-5906.00129