Controlling Inputter Variability in Vignette Studies Assessing Web-Based Symptom Checkers: Evaluation of Current Practice and Recommendations for Isolated Accuracy Metrics

András Meczner   ^{1, 2} , MSc, MD ;   Nathan Cohen   ¹ , BSc, MBBS, MSc ;   Aleem Qureshi   ¹ , BSc, MBBS ;   Maria Reza   ¹ , BSc, MBBS ;   Shailen Sutaria   ³ , MBBS, BMedSci, MSc ;   Emily Blount   ¹ , MBBS ;   Zsolt Bagyura   ² , MD, PhD ;   Tamer Malak   ¹ , BM, MSc, DPhil

¹ Healthily, London, United Kingdom

² Institute for Clinical Data Management, Semmelweis University, Budapest, Hungary

³ Independent Consultant in Public Health Medicine, London, London, United Kingdom