Analysis of Delphi study 7-point linear scale data by parametric methods: Use of the mean and standard deviation

The Delphi technique is a unique survey method that involves an iterative process to gain consensus when challenging establish. Survey participants typically rate variety of statements using specified rating scale. repeated for several rounds, and at each round do not reach predefined level are advanced the next while giving information about responses other their comparison. final then ranked in order average rating. statistical methods analyze studies well described. This study investigates use 1–7 linear scale along with parametric summary statistics assessment ranking statements. A set 9297 individual ratings on were obtained from previously performed used create 490,000 simulated various numbers participants. While overall distribution was strongly left skewed sampling near normally distributed five or more difference between standard deviation interquartile range −0.26/7. risk falsely concluding as statistic 7.3% compared range. mean median −0.20/7. by value 0.5 zero all sample sizes median. suggests combination valid studies.