The Development of Study Culture Assessment and Its Validation: Case Study of Thai Trucks Drivers


รศ.ดร.นันทา สู้รักษา, น.ส.supavanee Thimthong




Safety culture assessment is the instrument that can be used to capture employees’ perception about organizational safety culture in various dimensions. The main objective of this research was to investigate the constructs of multidimensional safety culture and consequently to develop a reliable and valid instrument to measure Thai truck driver’s perception on safety culture level in the workplace. This study employed the exploratory sequential mixed-method design ( i. e. qualitative research followed by quantitative research) to achieve the research objectives. The qualitative research was conducted using the indept interview with 12 subject matter experts ( e. g. 6 truck drivers, 3 logistics personnel, 2 safe-driving trainers, and 1 top management) in logistics industry using purposive sampling in order to determine the key constructs of safety culture in the context of Thai truck drivers. In accordance with the interview results, the existing accident causation model was applied to structure the key dimensions of safety culture. As a consequent, the key constructs were identified. Pool of items was generated adapting from existing instruments as well as newly developed based on the interview results. The first draft of safety culture assessment questionnaire was developed with 60 items altogether. Next step, the quantitative study was performed in order to examine reliability and validity of the newly developed scale. Firstly, the pilot test was conducted with 75 samples for item analysis purpose. At this stage of analysis, total of 19 items were removed. As a result, 41 items were remained for next analysis. The 41-item questionnaires were distributed to 1,010 truck drivers with 413 questionnaires returned, accounted for 40. 89% . These questionniares were then proceeded in the next level of analysis. Exploratory factor analysis ( EFA) was performed to identify sub-factors of each dimension. Eight sub-factors with total of 30 items were emerged as a result of EFA including management commitment, safety rules and training, supervisor support, co-worker support, work conditions, personal conditions, attentive action to safety, and supportive action to safety. Consequently, Confirmatory factor analysis (CFA) was performed to validate all the measurement constructs. The results suggested that the four-dimension safety culture model ( 30 items) had an acceptable fit with the data (RMSEA = 0.044, RMR = 0.020, CFI = 0. 997, GFI = 0. 989 and composite reliability = 0. 8987) . Therefore, the result supported the good reliability and convergent validity (CR = 0.90 and AVE = 0.53) of newly developed safety culture assessment. In order to examine the concurrent validity, two analyses were performed. First, partial correlation was used to examine the relationship between four safety dimensions and safety outcomes. The result revealed that employee safety behavior dimension had negative relationship with the likelihood of near-miss accident. In addition, the structural equation modeling (SEM) was later conducted to examine how safety culture influence safety outcomes. After adjusting the model, the results suggested that safety culture had a direct effect on both safety outcomes, as well as produced an indirect effect to the likelihood of accident transmitted through the likelihood of near-miss accident. As a consequent, the results showed evidence for good concurrent validity of the studied instrument. The paper also discussed the limitation of the study, the possible future research as well as implications for utilizing safety culture assessment.

(2556). รูปแบบการดำเนินชีวิต การเปิดรับสื่อ และความภักดีของผู้ฟังรายการวิทยุกรีนเวฟ. วารสารการประชาสัมพันธ์และการโฆษณา, 6(2), 107-119.