I haven't found scales for measuring 'meaningfulness of work'. However, in the workplace spirituality scale, one of its dimensions is 'Meaningful Work'. Please refer: Ashoms, D., & Duchon, D. (2000). Spirituality at work: A conceptualization and measure. Journal of Management Inquiry, 9(2), 124-145. http://dx.doi.org/10.1177/105649260092008.
Hirschi (2012) has a German translation of the Bunderson & Thompson (2009) scale.
Bunderson, J. S., & Thompson, J. A. (2009). The call of the wild: Zookeepers, callings, and the double-edged sword of deeply meaningful work. Administrative Science Quarterly, 54(1), 32-57.
Hirschi, A. (2012). Callings and work engagement: moderated mediation model of work meaningfulness, occupational identity, and occupational self-efficacy. Journal of Counseling Psychology, 59(3), 479-485.
"To assess work meaningfulness, we administrated three face valid questions: ‘I feel that my work has a meaning,’ ‘My work gives me a feeling of meaningfulness,’ and ‘Our work community does something valuable.’ The participants were asked to rate the extent to which they agreed with these statements on a scale from 1 (do not agree) to 7 (fully agree) (α = 0.91)." (Martela & Riekki, 2018, p. 4)
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