Objectives The aim of this study was to develop a questionnaire to measure work capabilities based on Amartya Sen’s capability approach and evaluate its validity.

Methods The development of the questionnaire was based on a combination of qualitative and quantitative methods: interviews, literature study, and an expert meeting. Additionally, in a survey, the validity was evaluated by means of hypotheses testing (using correlations and regression analyses).

Results The questionnaire consists of a set of seven capability aspects for work. For each aspect, it is determined whether it is part of a worker’s capability set, ie, when the aspect is considered valuable, is enabled in work, and is realized. The capability set was significantly correlated with work role functioning-flexibility demands (-0,187), work ability (-0.304), work performance (-0.282), worked hours (-0.073), sickness absence (yes/no) (0.098), and sickness absence days (0.105). The capability set and the overall capability item are significantly associated with all work outcomes (P<0.010).

Conclusions The new capability set for work questionnaire appears to be a valid instrument to measure work capabilities. The questionnaire is unique because the items include the valued aspects of work and incorporate whether a worker is able to achieve what (s)he values in his/her work. The questionnaire can be used to evaluate the capability set of workers in organizations to identify aspects that need to be addressed in interventions.

Key terms Amartya Sen; capability approach; capability set for work; questionnaire; questionnaire development; sustainable employability; validation; work

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