Widarsa is a public health expert, currently working as a senior lecturer in Biostatistics and Reproductive Health Division, Department of Public Health and Preventive Medicine, Faculty of Medicine, Universitas Udayana. He graduated as Medical Doctor from Universitas Udayana in 1977 and hold Master of Public Health from University of Hawaii-Manoa in 1983.

He teaches advance Biostatistics subject for public health student in School of Public Health, Universitas Udayana, especially for student undertaking biostatistics mainstream. He also teaches Biostatistics subject for medical student in Faculty of Medicine, Universitas Udayana.

He has publications in the international and national reputable journals and has granted HAKI (Copyrights) for two of his teaching books namely Buku Ajar Biostatistik Dasar and Buku Ajar Analisis Regresi dengan SPSS: Konsep, Prosedur dan Interpretasi.His research interest includes area around maternal-child health, non-communicable disease and application of biostatistics tests to health problem.