عوامل حیاتی موفقیت برای پایداری نتایج منابع انسانی حادثه کایزن: یک مطالعه تجربی

Kaizen events have been widely reported to produce positive change in business results and human resource outcomes. However, sustaining or improving upon the results of a Kaizen event over time can be difficult for many organizations and has received limited empirical research attention to date. This paper identifies the factors that most strongly influence the sustainability of work area employee attitudes and commitment to Kaizen events based on a field study of 65 events in eight manufacturing organizations. The findings also present guidelines for organizations and areas for future research.

The design of effective improvement programs continues to be a focus in the operations management (OM) and industrial engineering communities (e.g., Warnecke and Huser, 1995, Hales and Chakravorty, 2006, Kumar et al., 2008 and Chakravorty, 2009a). As a part of the continued academic study of improvement programs, researchers have recently explored critical success factors (e.g., Chan et al., 2005, Stock et al., 2007, Bayazit and Karpak, 2007 and Farris et al., 2009), the social system (i.e., human resource) and technical system (i.e., business-related) factors of improvement (e.g., Olorunniwo and Udo, 2002, Chakravorty, 2009b and Farris et al., 2009), and the long-term success of improvement efforts (e.g., Bayazit and Karpak, 2007). This paper addresses these areas of interest as they relate to Kaizen events, an increasingly common type of improvement mechanism. A Kaizen event is a “focused and structured improvement project, using a dedicated cross-functional team to improve a targeted work area, with specific goals, in an accelerated timeframe” (Farris et al., 2008, p. 10). In addition to a variety of technical system improvements, practitioners also report significant social system improvements from Kaizen events (e.g., Melnyk et al., 1998, Minton, 1998 and McNichols et al., 1999). Kaizen events are one way organizations seek to implement the broader concept of kaizen (Brunet and New, 2003), by introducing the concept of continuous improvement techniques and the development of an organizational culture that supports continuous improvement in the long-term. However, it can be difficult for many organizations to sustain the outcomes of a Kaizen event after it concludes (Bateman, 2005, Friedli, 1999 and Mackle, 2000). While previous research has examined immediate (i.e., initial) Kaizen event social and technical system outcomes (e.g., Farris et al., 2009) and the sustainability of technical system outcomes (e.g., Bateman, 2005), there is little research or practitioner guidance regarding the sustainability of human resource outcomes. Specifically, there is limited research about the factors that may promote the development of positive longer-term attitudes and commitment toward Kaizen events among employees in the targeted work area after the Kaizen event. This research contributes to the current body of knowledge by increasing the understanding of what factors most contribute to sustaining the human resource outcome work area attitude and commitment to Kaizen events. The present work represents the second phase of a multi-year Kaizen event research initiative and builds upon the first phase which identified critical success factors of initial Kaizen event outcomes, assessed immediately after the event's conclusion (i.e., Farris et al., 2009). In the overall study, both technical system and social system outcomes are measured; however, the scope of this paper focuses only on the social system outcome, work area attitude and commitment, while results related to other technical system and social system outcomes will be presented in future works. Using data from a field study of 65 Kaizen events across eight manufacturing organizations, multiple regression was used to test hypothesized relationships and to identify the critical success factors, i.e., variables, that are the most significant predictors of work area attitude and commitment. In addition to examining critical success factors for sustainability of work area attitude and commitment, the relationship between this longer-term social system outcome and the perceptions of attitude toward Kaizen events among team members immediately after the event were also explored. Qualitative data regarding event goals were used to further interpret the findings. Study results are used to develop recommendations for organizations using Kaizen events. The remainder of this paper is organized as follows. Section 2 presents the literature used to develop the working theory of Kaizen event outcome sustainability. Section 3 describes the research methodology, Section 4 presents the analysis results, and Section 5 concludes the paper with the research findings, limitations, and areas for future research.

5.1. Determinants of work area attitude and commitment Accepting changes was the strongest predictor of work area attitude and commitment (β=0.202, p=0.005). This is in alignment with previous research, which has suggested that management’s reinforcement of continuous improvement by regularly checking and raising continuous improvement awareness and the understanding of employees ( Kaye and Anderson, 1999), plays a primary role in supporting the sustainability of change. Furthermore, the mediation analysis found that production system changes and experimentation and continuous improvement were positively related to work area attitude and commitment through accepting changes. The finding related to production system changes aligns with previous research which found that organizations with flexible production capabilities, i.e., organizations that often and rapidly implement changes in product mix, etc., tend to create cultures that are more accepting of change in general ( Yeung et al., 1999). The finding that experimentation and continuous improvement impacted accepting changes (and thereby work area attitude and commitment), is also aligned with Yeung et al. (1999) as well as other previous research (e.g., Keating et al., 1999). Performance review was also found to be a significant, positive predictor of work area attitude and commitment, which suggests that the establishment of activities such as reviewing work area performance measures, conducting audits, and meeting with higher-level management regarding the Kaizen event progress encourages positive employee attitudes toward Kaizen events. This finding aligns with previous research that has reported that the use of measurement systems and related activities may increase visibility and employee awareness of change ( Bradley and Willett, 2004, Melnyk et al., 1998 and Tanner and Roncarti, 1994) and may prevent the deterioration of process-related improvements over time ( Bateman and Rich, 2003, Kaye and Anderson, 1999 and Dale et al., 1997). Acting indirectly through performance review, learning and stewardship and work area routineness were also positively related to work area attitude and commitment. This aligns with previous performance measurement research which has reported a positive relationship between performance review and organizational learning and stewardship (e.g. Kloot, 1997; Mausloff and Spence, 2008). However, the relationship has most often been hypothesized in the reverse of the direction studied in this research, i.e., performance review as a determinant of learning and stewardship. For instance, previous research in the continuous improvement domain has also found that performance review activities may serve as group learning experiences because they provide a platform to share experiences and progress on improvement projects ( Kaye and Anderson, 1999). It is also possible that performance review and organizational learning and stewardship share a bi-directional, reinforcing relationship, which could be a focus of future research. Meanwhile, the finding related to work area routineness suggests that performance review activities may be more effective in less complex work areas, due to difficulties in defining performance measures (e.g., Beamon, 1999) or greater variability in performance (e.g., Martin and Smith, 2005) for more complex work systems. Thus, companies with more complex work may want to consider additional strategies to offset this inherent disadvantage, e.g., more focus on developing learning and stewardship behaviors. Finally, experimentation and continuous improvement was also directly related to work area attitude and commitment. This finding is also aligned with previous studies, which have found that direct employee participation in designing changes ( Bradley and Willett, 2004, Melnyk et al., 1998 and Tanner and Roncarti, 1994), employee understanding of continuous improvement ( Kaye and Anderson, 1999), and employee understanding of the benefits of improvement via participation in continuous improvement activities (e.g., Keating et al., 1999) are critical to the continued success of an improvement program. In addition to the discussion of the significant variables, it should be noted that several model variables were not found to be significant predictors of work area attitude and commitment, after controlling for the most significant predictors, including: goal clarity, goal difficulty, management support, team functional heterogeneity, management change, employee change, institutionalizing change, and improvement culture. However, some of these variables were found to be significantly related to other sustainability outcomes ( Glover, 2010). 5.2. Relationship between immediate and long-term social system outcomes Based on the correlation analysis, there is no support for the relationship between the attitude of Kaizen event team members toward Kaizen events immediately after the event ( Farris et al., 2009) and work area attitude and commitment. The fact that attitude and work area attitude and commitment appear to be uncorrelated may be explained based on differences in the respondent, i.e., the respondents for attitude were the team members while the respondent for work area attitude and commitment was the facilitator or work area manager. However, this finding does at least partially align with previous research that suggests that positive attitudes at the conclusion of a successful event do not necessarily translate to sustained employee enthusiasm ( Doolen et al., 2008) and that work area employees may be more influential to the long-term sustainability of Kaizen event outcomes than the original Kaizen event team members ( Burch, 2008). Examination of the most significant predictors of attitude ( Farris et al., 2009) compared to those of work area attitude and commitment provides additional insight into the similarities and differences in the mechanisms underlying the development of both outcomes. As described in Farris et al. (2009), attitude toward events was positively related to management support and internal processes (a measure of team harmony) and negatively related to team functional heterogeneity (an index measuring the cross-functional diversity of the team). Thus, there are some clear differences between the most significant predictors of attitude compared to those of work area attitude and commitment. For example, team functional heterogeneity was not a predictor of work area attitude and commitment, measured at T1. There are also similarities to note between the predictors of attitude versus work area attitude and commitment. Both emphasize the role of group processes—i.e., having harmonious team processes during the event, accepting and following changes, practicing learning and stewardship, and experimentation and continuous improvement after the event. Both also include predictors that relate to the role of management, i.e., providing resources during the event, and promoting changes and holding employees accountable for adhering to changes after the event. These findings suggest that the two attitudinal outcome variables are strongly influenced by similar types of factors (i.e., group behaviors and management support), although the outcomes themselves are distinct and uncorrelated. 5.3. Findings from the qualitative analysis Qualitative observations of the Kaizen events with the highest and lowest work area attitude and commitment values suggest that managers may find it beneficial to periodically hold standard work events, e.g., using a standard work event to implement techniques that may enhance the acceptance of change and may encourage employees to follow new work methods, as they may help support the critical factors of work area attitude and commitment. In addition, managers may wish to place additional emphasis on those critical factors when using Kaizen events to address quality issues. 5.4. Limitations and future research The research design is an observational field study that sampled Kaizen events and their targeted work areas across multiple manufacturing organizations in order to test a working model of Kaizen event outcome sustainability. Key study limitations include those related to the size and nature of the sample, the consideration and treatment of organizational variables, the timing of the data collection, and the variables omitted from the research model. Each of these limitations is further discussed below, along with related areas for future research. The sample was limited in terms of the type, number, and geographic location of organizations, i.e., eight manufacturing organizations located in states on the East Coast and West Coast of the United States of America. Further research could consider a larger number of participating organizations from a wider variety of industries and additional geographic locations in order to increase the generalizability and robustness of the findings. For example, researchers have found that there are limitations with the transfer of some management innovations from other cultures e.g., the transfer of quality circles from Japan to the U.S., due to a lack of understanding of the organizational and strategic significance of the innovation (Lillrank, 1995), the lack of a supporting improvement infrastructure within the organizations (Ishikawa, 1985), and the existence of very different management paradigms and principles in U.S. organizations (Lillrank, 1995); i.e., a different organizational culture. The present research controlled for some organizational characteristics—for instance, the organizations studied all used Kaizen events as a mechanism within a structured, strategic Kaizen event program. However, further research should consider additional organizational characteristics, including, for example, comparing the sustainability of Kaizen event outcomes across organizations from varying cultures. Further, the residual analysis suggests that additional organizational variables may increase the predictive capabilities of the model. The continuous improvement literature hypothesizes that several organizational and external environmental variables may influence improvement sustainability, including organizational structure and policies (Dale et al., 1997), competitors (Dale et al., 1997 and Keating et al., 1999), and the ethnic diversity of the organizations. Future research, including the testing of additional organizational variables and the consideration of other multilevel modeling approaches, e.g., HLM, is thus needed to further understand the variation in the outcome across organizations. Due to limitations in collecting data (e.g., delayed data collection from respondents), data were collected at T0 (at the beginning and within four weeks of the Kaizen event) and at T1 (approximately nine to 18 months after the Kaizen event). Using a constant time difference between T0 and T1 (e.g., collecting all T1 data at exactly twelve months after the Kaizen event) could have strengthened the internal validity of the study (Davis and Cosenza, 1985), although clearly difficult to achieve in practice. In addition, future study of Kaizen events using a research design that considers the collection of data at more than two points in time would be beneficial (e.g., T0=immediately after the event, T1=6 months, T2=12 months, T3=18 months). Further, T1 survey data, e.g., Work Area Characteristics and Sustainability Outcomes, were collected from facilitators or work area managers as opposed to collecting the data directly from the workforce. While collecting data regarding the perceptions of the workforce throughout the research would have been beneficial, the approach in this research of using a facilitator or the work area manager to assess the perceptions of the workforce is supported as it has been used in previous studies of improvement teams (as summarized in Cohen and Bailey, 1997). Furthermore, it is possible that the data collected from the facilitator or manager may be more accurate than collecting data from the work area employees, because employees responding may not have been in the work area at the time of the Kaizen event (due to turnover), while the facilitator or manager responding to the questionnaire was present at the time of the Kaizen event. In addition, the research team made initial pilot attempts to survey work area employees as well, but this survey approach was discontinued due to low response rates. However, future research that collects data from both work area employees and facilitators/work area managers should be considered. Finally, this research did not attempt to study all Kaizen event characteristics, work area characteristics or post-event characteristics that could potentially impact the sustainability of work area attitude and commitment. Instead, the factors chosen for this research were selected from the Kaizen event body of knowledge and related theory as dominant, recurring factors indicated by multiple sources as likely determinants of event outcomes. For example, the impact of the facilitator’s experience and the need for the Kaizen event as perceived by the work area manager could also be included in future research, although they are currently at least partially reflected through other Kaizen event characteristics included in the model, e.g., management support. It should be noted that additional characteristics related to the experience and maturity of the organization and its use of Kaizen events should also be considered in modeling the sustainability of work area attitude and commitment resulting from Kaizen events in future research. Several organizational variables were reflected in this research either as controls (i.e., the organizational selection criteria) or measured work area characteristics, e.g., employee changes, or the turnover of work area employees since the Kaizen event, which was used to indirectly account for the use and percentage of temporary workers in the work area; however given the findings related to the non-homogeneity of error terms across organizations and the need to compare findings across different cultural contexts, additional research on the influence of organizational characteristics is needed. In summary, the present research has contributed to the body of Kaizen event knowledge and practice in a number of ways. To the authors’ knowledge, this research uses the largest sample size at the Kaizen event level to date (n=65), including both studies of Kaizen event initial outcomes and Kaizen event outcome sustainability. This research also identified and operationalized new Post-Event Characteristic survey scales. These scales can be used to inform future research on Kaizen events and other process improvement approaches. While these data collection instruments were used for research purposes in the participating companies, organizations could also use these instruments as a tool to manage Kaizen event activities. Thus, this work provides direction for both future research and future Kaizen event practice, based on large-sample, quantitative findings related to the most critical success factors for Kaizen activities and the development of supporting assessment methods and tools.