The effect of grammar teaching (sentence combining) in English on 5 to 16 year olds' accuracy and quality in written composition - Andrews, R; Torgerson, C; Beverton, S; Freeman, A; Locke, T; Low, G; Robinson, A; Zhu, D (2004)
review; evidence grade C

A meta-analysis of writing instruction for adolescent students. - Graham, S; Perin, D (2007)
meta-analysis; evidence grade C

The Effects of Peer-Assisted Sentence-Combining Instruction on the Writing Performance of More and Less Skilled Young Writers. - Saddler, B; Graham, S (2005)
rct; evidence grade C

The effect of grammar teaching on writing development - Andrews, R; Torgerson, C; Beverton, S; Freeman, A; Locke, T; Low, G; Robinson, A; Zhu, D (2006)
review; evidence grade C

A Meta-Analysis of Writing Instruction for Students in the Elementary Grades. - Graham, S; McKeown, D; Kiuhara, S; Harris, KR (2012)
meta-analysis; evidence grade C

Teaching grammar and writing: A randomised controlled trial and implementation process evaluation of Englicious - Wyse, D; Aarts, B; Anders, J; De Gennaro, A; Dockrell, J; Manyukhina, Y; Sing, S; Torgerson, C (2026)
rct; evidence grade B

A meta-analysis of single subject design writing intervention research. - Rogers, LA; Graham, S (2008)
meta-analysis; evidence grade D

A Quantitative Synthesis of Research on Writing Approaches in Grades 2 to 12. Best Evidence Encyclopedia (BEE) - Slavin, RE; Lake, C; Inns, A; Baye, A; Dachet, D; Haslam, J (2019)
meta-analysis; evidence grade B