Manitsas, David L. (dissertation) Short Term Mission Trips: A Vehicle for Developing
Personal and Spiritual Well-being. Newberg, Oregon: George Fox University, 2000.
Author administered the Spiritual Well-Being Scale (Paloutzian, 1983; Paloutzian & Ellison, 1982), the Tennnessee Self-Concept Scale, Second Edition (Fitts and Warren, 1996), and a survey of his own devising with questions about the STM experience and using the Likert-Scale, to members of a Baptist Church who went on a mission trip to Mexico.
Test administered 3 times (pre-trip, post-trip, 6 months after trip) to 3 groups: those who went on trip and had been on previous STMs (7 completed all three tests), those who went on the trip to Mexico as their first STM (7 completed all three tests), and a control group of people from the church who did not go on the trip to Mexico and had not been on any other STM (11 completed all three tests).
Comparison between the STM groups and the control group did not show significant difference on Spiritual Well-Being or Self-Concept scales; in the Likert-Scale questions and anecdotal responses, however, STM participants reported feeling closer to God, being more committed to Christian service, and more likely to participate in another STM than they had been previously.
Author also notes that "except for being more likely to participate in a future short-term mission trip, these gains were not sustained through a 6 month follow-up." (p. 38)