Reliability Validity of the Construction Delay Questionaire using the Rasch Mesurement Model

Construction industry is one of the industry that generates economy and at the same time provides job vacancy and national treasure. However, delay in construction project is a global phenomenon which occurred at almost every country, thus retards the development of the country. There are numerous of studies on construction delay using questionnaire done by researchers worldwide. Reliability and validity of the questionnaire should be reviewed in advance to ensure the effectiveness of the survey conducted. It is to obtain the appropriate data and the data can be used for futher analysing. The objective of this research is to get the reliability and validity of the questionnaire on construction delays projects using the Rasch measurement model. For purposes of data analysis, this research uses Winstep a software-based Rasch Modal measurement. Beside Cronbach alpha reliability, Rasch Measurement Model can provide the reliability of the item and respondent. Validity of data evaluated from various aspects, including the items and the respondent misfit, principal component analysis and rating scale. A total of 54 of the 64 items were identified contributed to delays in construction projects in Malaysia.