[1] Glasgow Caledonian Univ, Cowcaddens Rd, Glasgow G4 0BA, Lanark, Scotland
[2] Heriot Watt Univ, Edinburgh, Midlothian, Scotland
[3] NHS Forth Valley, Stirling, Scotland
[4] Univ Victoria, Canadian Inst Subst Use Res, Victoria, BC, Canada
[5] Univ Stirling, Fac Hlth Sci & Sport, Nursing Midwifery & Allied Hlth Profess Res Unit, Stirling, Scotland