Evaluating networked drug checking services in Toronto, Ontario: study protocol and rationale oleh N. Maghsoudi, K. McDonald, C. Stefan, D. R. Beriault, K. Mason, L. Barnaby, J. Altenberg, R. D. MacDonald, J. Caldwell, R. Nisenbaum, P. Leece, T. M. Watson, K. W. Tupper, L. Kufner, A. I. Scheim, D. Werb, Drug Checking Services in Toronto Working Group