The Delphi survey technique is an iterative mail or electronic (e-mail or web-based) survey method used to obtain agreement or consensus among a group of experts in a specific field on a particular issue through a well-designed and systematic multiple sequential rounds of survey administrations. Each of the multiple rounds of the Delphi survey administration is augmented with continuous summary feedback of aggregated responses from the same group of experts. Statistical methods to analyze data from the Delphi surveys to make decisions for terminating subsequent Delphi data collection are needed to ensure that (a) stability of the responses of the panel of experts is reached; and (b) termination of the rounds of the Delphi survey administration is based on sound statistical results. The present study presents an overview of the parametric and nonparametric statistical methods that can be used to analyze the structured Delphi survey data to make decisions about terminating the sequential Delphi survey data collection. Accessed 9,961 times on https://pareonline.net from January 23, 2012 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right.