Table 1. Variables hypothesized to influence compliance with protected area (PA) policies and categorized into four key types of factors

PA characteristics
Existence of buffer zones
IUCN category
WDPA 2009
published studies identified in systematic review
Social characteristics
Population density
Country adult literacy rates
CIESIN and CIAT 2005
International Monetary Fund (IMF) 2011
Availability of resources
GDP PPP (purchasing power parity) per capita
PA budget per country
PA staff number per km2 per country
IMF 2011
James et al. 1999
James et al. 1999
PA management approach
Level of local community participation in PA management
Published studies identified in systematic review