Table 1.

Study Characteristics

Primary ref	Ref	Additional paper refs	Study type and report type	Country	Design	N	% women	Mean age	Participants	Activity descriptors and environment	Intensity	Comparator	Quality grading
Barton et al. 2009	[46]	[91, 92]	Quantitative, thesis and peer reviewed articles	UK	uBA	19	26	~60	Volunteers	Conservation. Rural natural environment.	NR	Active recreation	Weak
Brooker and Brooker 2008a	[42]a		Quantitative, unpublished case study	UK	N of 1 uBA	1	100	49	Volunteers	Green Gym. Rural natural environment.	“Regular”	Other physical activity	Weak
Brooker and Brooker 2008aa	[43]a		Quantitative, unpublished case study	UK	N of 1 uBA	1	100	49	Volunteers	Green Gym. Rural natural environment.	“Regular”	Other physical activity	Weak
BTCV 2009	[36]		Quantitative, unpublished evaluation report	UK	uBA	122	47	9	School pupils	Green Gym. Mixed natural environments.	1 – 1.5 hours per week	N/A	Weak
Eastaugh et al. 2010	[33]		Quantitative, unpublished evaluation report	UK	uBA	8	NR	NR	Referred and voluntary	Conservation. Woodlands.	NR	N/A	Weak
Moore et al. 2006	[44]		Quantitative, peer reviewed article	Australia	Case control	102	37	55	Volunteers	Conservation. Rural natural environment.	NR	Community members not involved in conservation	Weak
Pillemer et al. 2010	[45]		Quantitative, peer reviewed article	Canada	Cohort	2630	57	45	NR	Conservation. No detail on environment.	NR	Alternative volunteering	Weak
Reynolds 1999a	[47]	[93]	Quantitative, peer reviewed article and unpublished evaluation report	UK	uBA	16	49	60	Volunteers	Green Gym. Rural natural environment.	3 hours twice a week	N/A	Weak
Small Woods 2011	[40]	[94]	Quantitative, unpublished evaluation reports	UK	uBA	7	100	NR	Referred	Woodland management. Woodlands.	NR	N/A	Weak
Yerrell 2008	[41]		Quantitative, unpublished evaluation report	UK	uBA	194	40	45	Volunteers and referred	Green Gym. Mixed natural environments.	1-4 hours once a week	N/A	Weak
Birch 2005	[48]		Qualitative, peer reviewed article	UK	Interviews, ethnographic	3	67	42	Volunteers	Green Gym. Rural natural environment.	3 hrs twice weekly	N/A	Poor
Burls 2007	[34]		Qualitative, peer reviewed article	UK	Focus groups, ethnographic	11	NR	NR	Volunteers	Conservation gardening. Urban natural environments.	NR	N/A	Poor
Carter and O'Brien 2008	[39]	[95]	Qualitative, unpublished evaluation report	UK	“qualitative evaluation”	NR	NR	NR	Referred	Habitat Restoration. Rural natural environments, woodlands	1-2 days per week for 6 months	N/A	Poor
Christie 2004	[49]		Qualitative, unpublished report	Australia	Interviews	18	NR	30	Volunteers	Bush Regeneration. Rural natural environment.	NR	N/A	Poor
Gooch 2005	[35]		Qualitative, peer reviewed article	Australia	Interviews	85	NR	NR	Volunteers	Conservation activities. Natural environments, water catchments.	NR	N/A	Poor
Halpenny and Caissie 2003	[50]	[96]	Qualitative, peer reviewed articles	Canada	Interviews	10	50	40	Volunteers	Restoring habitats. Rural natural environments.	3-17 day vacations	N/A	Good
Miller et al. 2002	[37]		Qualitative, peer reviewed article	USA	Focus groups, ethnographic	30	NR	19	Students	Trail creation. Urban natural environments.	1 day per week for 10 weeks	N/A	Poor
O'Brien et al. 2011	[53]		Qualitative, peer reviewed article	UK	Ethnographic	10	40	40	Volunteers	Wildlife gardening. Urban natural environment.	2-3 days per week	N/A	Good
Townsend and Marsh 2004	[52]		Qualitative, unpublished evaluation report	Australia	Interviews, focus groups	NR 18+	33	65	Volunteers	Restoration of reserve. Rural natural environment.	NR	N/A	Poor
Townsend 2006	[51]	[97]	Qualitative, peer reviewed article and unpublished evaluation report	Australia	Interviews	35	NR	NR	Volunteers	Maintenance of creek and reserves. Rural natural environment.	NR	N/A	Poor
BTCV 2010	[38]		Mixed, unpublished evaluation report	UK	uBA	136	NR	NR	Volunteers and referred	Green Gym. Rural natural environment.	NR	N/A	Weak
					Interviews	19	16	NR					Poor
O'Brien et al. 2010	[54]	[98]	Mixed, peer reviewed article and unpublished evaluation report	UK	uBA	88	28	43	Volunteers	Vegetation Clearing. Rural natural environment.	0 - 33 hrs per month	N/A	Weak
					Interviews, ethnographic								Good
Wilson 2009	[32]		Mixed, unpublished evaluation report	UK	uBA	77	26	41	Referred	Conservation. Rural natural environment, woodlands.	3 hours per week for 12 weeks	N/A	Weak
					Interviews								Poor

^aStudies not included in the synthesis due to small n. uBA, uncontrolled Before and After study. N/A, Not Applicable. NR, Not Reported