A Causal Model of Factors Influencing Hospital Decisions to Use Wastewater Treatment Pond Maintenance Services in The Bangkok Metropolitan Area

Research Objective: This article aimed to examine (1) the levels of service quality, 7Ps marketing mix, trust, and decision-making regarding wastewater treatment pond maintenance services among hospitals in the Bangkok Metropolitan Area and its surrounding area, (2) to develop and validate a causal model of decision-making for wastewater treatment pond maintenance services, and (3) to examine the influence of service quality, 7Ps marketing mix, and trust on hospital decision-making to use wastewater treatment pond maintenance services. Research design, data and methodology: The sample consisted of 300 personnel who were responsible for or involved in decision-making regarding wastewater treatment pond maintenance services in hospitals in Bangkok and surrounding areas. They were selected by purposive sampling. The instrument for collecting data was a structured questionnaire. Data were analyzed using descriptive statistics and structural equation modeling. Results: 1) The Respondents rated service quality, 7Ps marketing mix, trust, and decision-making at a high level overall. The proposed causal model demonstrated a good fit with the empirical data, showing that the measurement and structural models were proper and consistent with the theoretical framework. 2) The model proved acceptable; goodness-of-fit indices (χ²/df = 2.221, CFI = 0.973, GFI = 0.935, RMSEA = 0.064, RMR = 0.015), and the independent variables explained 72% of the variance in trust and 84% of the variance in decision-making. 3) The 7Ps marketing mix had the strongest total effect on decision-making, followed by trust and service quality. Trust significantly mediated the relationship between service quality, 7Ps marketing mix, and decision-making, confirming its crucial role as a key intervening variable in hospital service selection decisions.