Synonym Identification for 'Preliminary'

After years of dedicated research, Dr. Harris finally made a breakthrough in her field, discovering a method that could possibly cure a previously untreatable disease. Her findings were met with great enthusiasm at the conference, where many peers applauded her continued perseverance. However, some critics were quick to express their skepticism, calling the results preliminary and demanding further evidence to validate her claims. In this context, what is the best synonym for 'preliminary'?