The various type of services provided by contract research organizations to biopharmaceutical companies in the drug development process include initial drug discovery studies, pre-clinical studies, early clinical trial phase I-IIa, phase IIb-III, phase IIIb-IV and others. The others segment include various support services such as pharmacovigilance, bio-statistics, clinical data management, site management, monitoring, regulatory services, protocol development and medical writing. Clinical trials typically differ by phase and type. Clinical trials primarily aimed to develop new strategies or products to prevent, detect, and treat disease and to improve overall quality of life of people who are suffering with various diseases.