inability comply protocol requirements assessments investigator follow available study willing unable comply protocol requirements opinion investigator follow study patient consent monitoring safety comply opinion requirements able investigator study eligible patients noncompliance regimens medical history haart unreliable protocol comply unable therapy unwilling follow unable requirements protocol consent instruction informed render instructions abide cooperate fully unwilling designee unable protocol investigator study subject addictive preclude psychiatric disorders meeting conditions requirements opinion patient investigator unwilling comply unable protocol patients requirements study procedures assessed investigator exclude opinion investigator subject presence following study enrollment patient patients compliant initiative investigator means protocol patient opinion proximity team study