op21_a
Op21 AField Label
Over your lifetime, when were you taking (substance) the most? how long did that period last? during that time, how often were you taking it? how much were you using?
Branching Logic
[op21] = '1'
Field Label
Over your lifetime, when were you taking (substance) the most? how long did that period last? during that time, how often were you taking it? how much were you using?
Branching Logic
[op21] = '1'