Study	Reason for exclusion
Atlas 2011	Communication was one‐way rather than two‐way between healthcare professionals.
Chen 2010	Communication was one‐way rather than two‐way between healthcare professionals.
Cline 2007	Study never completed, as confirmed by trialist.
Dalal 2012	Communication was one‐way rather than two‐way between healthcare professionals.
Edward 2007	Communication was one‐way rather than two‐way between healthcare professionals.
Feldman 2005	Communication was one‐way rather than two‐way between healthcare professionals.
Jaatinen 2002	Email component was not assessed separately from the rest of the intervention.
Johansson 2009	Communication was one‐way rather than two‐way between healthcare professionals.
Kerfoot 2010	Intervention was primarily educational in content.
Lester 2004	Communication was one‐way rather than two‐way between healthcare professionals.
Lester 2006	Communication was one‐way rather than two‐way between healthcare professionals.
Lobach 2013	Communication was one‐way rather than two‐way between healthcare professionals.
Mandall 2005	Communication was one‐way rather than two‐way between healthcare professionals.
McKee 2011	Multifaceted Internet intervention with an email component. The effects of email were not individually reported.
Murtaugh 2005	Same study as Feldman 2005. Feldman 2005 presented patient outcomes, Murtaugh 2005 presented healthcare professional outcomes in the context of nurse education. Studies concerned with email solely for educational purposes were excluded from this review.
Persell 2008	Email component was not assessed separately from the rest of the intervention.
Quan 2013	Excluded on basis of study design, this was a pre‐post mixed methods study
Schopf 2012	Intervention was primarily educational in content.
Ward 2008	Multifaceted Internet intervention with an email component. The effects of email were not individually reported. Communication was one‐way rather than two‐way between healthcare professionals.