Advantages • Animal • Assigned • Been • Between • Blinded • Comparison • Controlled • Data • Demographi • Double • Easier • Effectiveness • Either • Ethical • Given • Harmless • Helps • Increasing • Individually • Involves • Less • Make • Measure • Medical • Observational • Observed • Procedure • Provide • Purpose • Qualitative • Randomized • Receive • Reducing • Rigorous • Risk • Selecting • Studied • Studies • Sure • Their • There • They • To. • Treatment • Treatments • Type • Validity • Way • Who