Table 2: Summary of coaching effectiveness studies included in the meta-analysis. Authors Sample Country Organizational Occupation of Outcomes Research Coaching Longevity of Duration Number Format of context participants measured design technique intervention1 of sessions of coaching sessions2 feedback Bozer & 96 Israel Various Management Affective Between 15.2 weeks 30 120 6-8 Not – Sarros, Skill-based subjects minutes specified 2012 telephone & e-mail Bright & 115 US Various Various Affective Between Not 4 weeks 30 minutes 1 No Telephone Crockett, subjects specified 2012 Cerni, 14 US Education Principals Skill-based Between Epstein's 10 weeks 60 minutes 10 No Curtis & Subjects constructive Colmar, thinking 2010 programme (1998) Evers, 60 US Government Management Affective Between GROW 17.3 weeks Not Not No Not Brouwers & Agency subjects model specified specified specified Tomic, (Whitmore, 2006 1992) Finn, 2007 17 Australia Not specified Senior Affective Between Not 12 weeks 60 minutes 6 Yes management Skill-based subjects specified and telephone` Grant, 41 Australia Health Executives & Affective Between 10 weeks Not 4 Yes Curtayne & senior Results subjects specified and Burton, managers solution telephone 2009 focussed (Grant, 2003) GROW model (Whitmore, 1992) Grant, 44 Australia Education Teachers Affective Between 20 weeks Not 10 Yes
Table 2: Summary of coaching effectiveness studies included in the meta-analysis. Authors Sample Country Organizational context Occupation of participants Outcomes measured Research design Coaching technique Longevity of intervention1 Duration of sessions Number of sessions2 feedback Format of coaching Bozer & Sarros, 2012 96 Israel Various Management Affective Skill-based Between subjects 15.2 weeks 30 – 120 minutes 6-8 Not specified telephone & e-mail Bright & Crockett, 2012 115 US Various Various Affective Between subjects Not specified 4 weeks 30 minutes 1 No Telephone Cerni, Curtis & Colmar, 2010 14 US Education Principals Skill-based Between Subjects Epstein's constructive thinking programme (1998) 10 weeks 60 minutes 10 No Evers, Brouwers & Tomic, 2006 60 US Government Agency Management Affective Between subjects GROW model (Whitmore, 1992) 17.3 weeks Not specified Not specified No Not specified Finn, 2007 17 Australia Not specified Senior management Affective Skill-based Between subjects Not specified 12 weeks 60 minutes 6 Yes and telephone` Grant, Curtayne & Burton, 2009 41 Australia Health Executives & senior managers Affective Results Between subjects solution focussed (Grant, 2003) GROW model (Whitmore, 1992) 10 weeks Not specified 4 Yes and telephone Grant, 44 Australia Education Teachers Affective Between 20 weeks Not 10 Yes