31 Conceptualization and Measurement of Proactive Vitality Management that proactive vitality management can be adequately and reliably measured with the proposed eight-item instrument. STUDY 2: DAILY PROACTIVE VITALITY MANAGEMENT Study 1 showed that PVM can be reliably measured with a short eight-item scale that represents one overall factor. To test whether these psychometric properties also hold at the day-level, we conducted a second study using a heterogeneous sample. In this diary study, we test the reliability and validity of the daily PVM scale. In addition, we aim to gain insights into example strategies individuals may use to manage their vitality. Therefore, we examine how the PVM construct relates to the daily use of work-related strategies and micro-breaks at work (Fritz et al., 2011; Zacher et al., 2014). METHOD Procedure and Participants To examine PVM on a daily level, we conducted a five-day diary study using the same items, yet adapted to the day-level (e.g., “Today I made sure that I felt energetic during my work” – see Table 1 for all the items). Participants for this study were recruited via Amazon Mechanical Turk (MTurk), and were paid for their participation through this platform. While some people accentuate the potential pitfalls of this particular data collection method, studies have shown that it is an adequate way to gather data (e.g., Buhrmester, Kwang, & Gosling, 2011). Another advantage is that this method allows us to validate the PVM scale in an English-speaking (American) sample as well, which adds to the generalizability of the scale. Individuals were required to work fulltime to be able to participate in the diary study. To ensure high quality data, another criterion was that participants had to have a good ‘reputation’ on MTurk (i.e., above 95% approval ratings), which represents the quality of their past responses and data entries in the system (cf. Peer, Vosgerau, & Acquisti, 2014). Participants were instructed to fill out each daily questionnaire at the end of their working day, over the course of five consecutive workdays. We asked participants to fill in their MTurk ID at the beginning 2

RkJQdWJsaXNoZXIy MTk4NDMw