comprehend informed consent able sign document written willing subjects form 
written informed consent given provides obtained able participate patient study 
irb approved sign document informed understand consent willing written able 
specific study entry consent informed provide prior patient sign patients 
understand able sign consent informed document willing patients read patient 
sign consent informed patients able willing written refusal document patient 
legally authorized representative consent informed written provide patient sign understand 
document sign understand written consent willing informed able patient patients 
unwillingness inability consent informed supplementation written transfused vitamin individual folic 
guardians parents legal sign consent written informed patients benefits indicating 
able consent informed willing patients patient subjects study participants eligible 
pertinent aspects informed dated indicating signed document consent legally trial 
comply able protocol informed consent sign requirements signed willing icf 
inability consent informed provide understand written obtain assent document sign 
legal representative consent informed able written provide patient understand sign 
unwilling unable consent informed sign form document written patients icd