Author

No. of Students

Teaching context

Gu (2009)

50

China

Jimakorn & Singhasiri (2006)

35 - 100

Not mention

Lei (2015)

around 80

China

Li (2008)

60 - 150

China

Mulryan-Kyne (2010)

300 - 1000

Not mention

Nakabugo, Opolot-Okurut, Ssebbunga, Manni, & Byamugisha (2008)

70

Uganda

Nakabugo et al. (2008)

above 40

Japan

Nakabugo et al. (2008)

above 60

Developing countries

Nakabugo, Albert & Maani, (2006)

40

Kenya

O’Sullivan (2006)

above 35

US

Smith & Warburton (1997)

25 - 30

UK

Ur (1996)

40 - 50

Not mention

Wang (2002)

70 - 80

China

Yang & Yang (2006)

60

China

Yang (2008)

around 60

China

Yuan (2004)

50

China