Since your college/university might have a "human subjects institutional review board" or "office of regulatory compliance" you might want to check with them first. Certainly receiving legal advice from the "net" is risky behaviour. -- co-owner INFOSYS, TQM-L, CPARK-L, ERAPPA-L, JANITORS, LDBASE-L, et -L URL:mailto:[log in to unmask] "I've fallen and can't reach my keyboard" 31 Shields Bldg. -- Penn State -- University Park, PA 16802-1202 USA