The effects of task complexity on Chinese learners’ language production: A synthesis and meta-analysis

The  present  meta-analysis  was  conducted  to  provide  a  quantitative  measure  of  the overall effects of task complexity on Chinese EFL learners’ language  production.  Based  on  the strict inclusion criteria, 12 primary  studies  were synthesized according to key  features.  Eleven of them  were  meta-analyzed  to  investigate  effects  of  raising  the  resource-directing  task  complexity. Results revealed that (a) there was an assortment of treatments and measures, (b) there was a small to medium positive effect for syntactic complexity (d=0.64) and small effect for lexical complexity (d=0.20),  which  lends  support  to  the  Cognition  Hypothesis;  there  was  a  small  negative  effect  for accuracy (-0.18) and a close to negative effect (0.01) for fluency in writing, which partly confirms Skehan’s  Trade-off  effects,  and  (c)  task  modality  (oral  or  written)  did  not  make  a  significant difference on the overall effects on complexity and accuracy,  while  make a significant  difference on fluency.